1

1

AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
+    <uses-permission android:name="com.android.launcher.permission.INSTALL_SHORTCUT" />
+    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.READ_CONTACTS" />
+    <uses-permission android:name="android.permission.MANAGE_ACCOUNTS" />
+    <uses-permission android:name="android.permission.AUTHENTICATE_ACCOUNTS" />
+    <uses-permission android:name="android.permission.GET_ACCOUNTS" />
+    <uses-permission android:name="android.permission.USE_CREDENTIALS" />
+    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
+
+    <application
+        android:allowBackup="true"
+        android:dataExtractionRules="@xml/data_extraction_rules"
+        android:fullBackupContent="@xml/backup_rules"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:roundIcon="@mipmap/ic_launcher_round"
+        android:supportsRtl="true"
+        android:theme="@style/Theme.Notesmaster"
+        tools:targetApi="31">
+
+        <activity
+            android:name=".ui.NotesListActivity"
+            android:configChanges="keyboardHidden|orientation|screenSize"
+            android:label="@string/app_name"
+            android:launchMode="singleTop"
+            android:theme="@style/NoteTheme"
+            android:uiOptions="splitActionBarWhenNarrow"
+            android:windowSoftInputMode="adjustPan"
+            android:exported="true">
+
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+
+        <activity
+            android:name=".ui.NoteEditActivity"
+            android:configChanges="keyboardHidden|orientation|screenSize"
+            android:launchMode="singleTop"
+            android:theme="@style/NoteTheme"
+            android:exported="true">
+
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <data android:mimeType="vnd.android.cursor.item/text_note" />
+                <data android:mimeType="vnd.android.cursor.item/call_note" />
+            </intent-filter>
+
+            <intent-filter>
+                <action android:name="android.intent.action.INSERT_OR_EDIT" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <data android:mimeType="vnd.android.cursor.item/text_note" />
+                <data android:mimeType="vnd.android.cursor.item/call_note" />
+            </intent-filter>
+
+            <intent-filter>
+                <action android:name="android.intent.action.SEARCH" />
+                <category android:name="android.intent.category.DEFAULT" />
+            </intent-filter>
+
+            <meta-data
+                android:name="android.app.searchable"
+                android:resource="@xml/searchable" />
+        </activity>
+
+
+        <provider
+            android:name="net.micode.notes.data.NotesProvider"
+            android:authorities="micode_notes"
+            android:multiprocess="true" />
+
+        <receiver
+            android:name=".widget.NoteWidgetProvider_2x"
+            android:label="@string/app_widget2x2"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
+                <action android:name="android.appwidget.action.APPWIDGET_DELETED" />
+                <action android:name="android.intent.action.PRIVACY_MODE_CHANGED" />
+            </intent-filter>
+
+            <meta-data
+                android:name="android.appwidget.provider"
+                android:resource="@xml/widget_2x_info" />
+        </receiver>
+        <receiver
+            android:name=".widget.NoteWidgetProvider_4x"
+            android:label="@string/app_widget4x4"
+            android:exported="true">
+
+            <intent-filter>
+                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
+                <action android:name="android.appwidget.action.APPWIDGET_DELETED" />
+                <action android:name="android.intent.action.PRIVACY_MODE_CHANGED" />
+            </intent-filter>
+
+            <meta-data
+                android:name="android.appwidget.provider"
+                android:resource="@xml/widget_4x_info" />
+        </receiver>
+
+        <receiver android:name=".ui.AlarmInitReceiver"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.intent.action.BOOT_COMPLETED" />
+            </intent-filter>
+        </receiver>
+
+        <receiver
+            android:name="net.micode.notes.ui.AlarmReceiver"
+            android:process=":remote" >
+        </receiver>
+
+        <activity
+            android:name=".ui.AlarmAlertActivity"
+            android:label="@string/app_name"
+            android:launchMode="singleInstance"
+            android:theme="@android:style/Theme.Holo.Wallpaper.NoTitleBar" >
+        </activity>
+
+        <activity
+            android:name="net.micode.notes.ui.NotesPreferenceActivity"
+            android:label="@string/preferences_title"
+            android:launchMode="singleTop"
+            android:theme="@android:style/Theme.Holo.Light" >
+        </activity>
+
+        <service
+            android:name="net.micode.notes.gtask.remote.GTaskSyncService"
+            android:exported="false" >
+        </service>
+
+        <meta-data
+            android:name="android.app.default_searchable"
+            android:value=".ui.NoteEditActivity" />
+
+        <!--        <activity-->
+        <!--            android:name=".MainActivity"-->
+        <!--            android:exported="true">-->
+        <!--            <intent-filter>-->
+        <!--                <action android:name="android.intent.action.MAIN" />-->
+
+        <!--                <category android:name="android.intent.category.LAUNCHER" />-->
+        <!--            </intent-filter>-->
+        <!--        </activity>
+        ### 总体分析
+这是一个安卓（Android）应用的`manifest`（清单）文件，它在安卓开发中起着至关重要的作用，用于向安卓系统声明应用的各种关键信息，包括所需的权限、包含的组件（如活动、服务、广播接收器、内容提供者等）以及这些组件的相关配置和属性等内容，是安卓系统了解和管理应用的重要依据。
+
+### 权限声明部分
+- 声明了多个权限，例如：
+    - `WRITE_EXTERNAL_STORAGE`：允许应用写入外部存储，可用于保存文件、缓存数据等操作到手机存储设备上。
+    - `COM.android.launcher.permission.INSTALL_SHORTCUT`：使应用具备创建桌面快捷方式的权限，方便用户快速启动应用。
+    - `INTERNET`：应用若要进行网络相关操作（如联网获取数据、与服务器交互等），需要此权限。
+    - `READ_CONTACTS`：赋予应用读取手机联系人信息的能力，可用于诸如关联联系人进行相关功能实现等场景。
+    - 还有涉及账户管理（`MANAGE_ACCOUNTS`、`AUTHENTICATE_ACCOUNTS`、`GET_ACCOUNTS`、`USE_CREDENTIALS`）以及接收开机完成广播（`RECEIVE_BOOT_COMPLETED`）等权限，整体涵盖了应用在存储、交互、系统功能关联等多方面可能需要的权限内容。
+
+### 应用配置部分
+- **`application`标签内**：
+    - 设置了允许应用备份（`allowBackup="true"`），并指定了数据提取规则（`dataExtractionRules`）和全量备份内容（`fullBackupContent`）对应的 XML 文件，定义了备份相关的行为规范。
+    - 配置了应用图标（`icon`）、标签名称（`label`）、圆形图标（`roundIcon`）、对 RTL（从右到左）布局的支持（`supportsRtl="true"`）以及应用的主题（`theme`）等基本显示和布局相关属性，用于确定应用在用户界面呈现方面的一些特征。
+
+### 组件声明部分
+- **活动（`activity`）组件**：
+    - `NotesListActivity`：是应用的一个重要活动，配置了诸如屏幕方向变化、键盘隐藏等配置变化时的处理方式（`configChanges`），启动模式（`launchMode`）为`singleTop`，设置了特定的主题（`theme`）和软键盘弹出时窗口调整模式（`windowSoftInputMode`）等，并且通过`intent-filter`设置其为应用的主启动入口（包含`android.intent.action.MAIN`和`android.intent.category.LAUNCHER`），用户点击应用图标启动应用时首先进入的就是这个活动。
+    - `NoteEditActivity`：具备类似的部分配置属性（如`configChanges`、`launchMode`、`theme`等），同时通过多个`intent-filter`定义了它能响应的不同意图动作，比如查看、插入或编辑特定类型（文本笔记、通话记录笔记）的笔记内容，以及处理搜索相关操作等，还关联了一个用于搜索配置的`meta-data`，表明其在笔记编辑以及搜索相关功能实现方面有着重要作用。
+    - 还有如`AlarmAlertActivity`、`NotesPreferenceActivity`等其他活动，各自有着不同的标签、启动模式和主题配置，用于在应用中实现闹钟提醒展示、偏好设置等不同功能场景。
+- **内容提供者（`provider`）组件**：
+声明了名为`net.micode.notes.data.NotesProvider`的内容提供者，其授权字符串（`authorities`）为`"micode_notes"`，并设置了可多进程使用（`multiprocess="true"`），用于在应用内不同组件间共享数据，比如数据库数据等，方便其他组件对数据进行访问和操作。
+- **广播接收器（`receiver`）组件**：
+    - 像`NoteWidgetProvider_2x`和`NoteWidgetProvider_4x`这类广播接收器，用于接收如应用小部件更新、删除以及隐私模式改变等相关广播动作，并且通过`meta-data`关联了对应的小部件配置信息文件，在实现应用桌面小部件功能以及响应相关系统状态变化方面发挥作用。
+    - 还有`AlarmInitReceiver`用于接收开机完成广播来进行闹钟相关的初始化操作，`AlarmReceiver`用于其他与闹钟相关的功能（虽然这里未详细展示其内部具体逻辑），共同构建起闹钟提醒相关的功能逻辑体系。
+- **服务（`service`）组件**：
+声明了`net.micode.notes.gtask.remote.GTaskSyncService`服务，不过设置其为不对外导出（`exported="false"`），意味着它主要供应用内部使用，可能用于执行如数据同步等后台任务，在保证应用数据一致性等方面提供支持。
+
+### 其他配置部分
+- 通过`meta-data`配置了应用默认的搜索相关活动（指定为`ui.NoteEditActivity`），用于确定当用户发起搜索操作时默认进入的页面等搜索相关的行为引导。
+
+此外，文件中还有部分被注释掉的`activity`（如`MainActivity`相关代码），这部分代码当前是不生效的，可能是开发过程中暂时废弃或者后续可能会启用的功能模块对应的配置内容。
+
+        -->
+
+
+    </application>
+
+</manifest>

GTaskStringUtils.java

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+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.tool;
+
+public class GTaskStringUtils {
+
+    public final static String GTASK_JSON_ACTION_ID = "action_id";
+
+    public final static String GTASK_JSON_ACTION_LIST = "action_list";
+
+    public final static String GTASK_JSON_ACTION_TYPE = "action_type";
+
+    public final static String GTASK_JSON_ACTION_TYPE_CREATE = "create";
+
+    public final static String GTASK_JSON_ACTION_TYPE_GETALL = "get_all";
+
+    public final static String GTASK_JSON_ACTION_TYPE_MOVE = "move";
+
+    public final static String GTASK_JSON_ACTION_TYPE_UPDATE = "update";
+
+    public final static String GTASK_JSON_CREATOR_ID = "creator_id";
+
+    public final static String GTASK_JSON_CHILD_ENTITY = "child_entity";
+
+    public final static String GTASK_JSON_CLIENT_VERSION = "client_version";
+
+    public final static String GTASK_JSON_COMPLETED = "completed";
+
+    public final static String GTASK_JSON_CURRENT_LIST_ID = "current_list_id";
+
+    public final static String GTASK_JSON_DEFAULT_LIST_ID = "default_list_id";
+
+    public final static String GTASK_JSON_DELETED = "deleted";
+
+    public final static String GTASK_JSON_DEST_LIST = "dest_list";
+
+    public final static String GTASK_JSON_DEST_PARENT = "dest_parent";
+
+    public final static String GTASK_JSON_DEST_PARENT_TYPE = "dest_parent_type";
+
+    public final static String GTASK_JSON_ENTITY_DELTA = "entity_delta";
+
+    public final static String GTASK_JSON_ENTITY_TYPE = "entity_type";
+
+    public final static String GTASK_JSON_GET_DELETED = "get_deleted";
+
+    public final static String GTASK_JSON_ID = "id";
+
+    public final static String GTASK_JSON_INDEX = "index";
+
+    public final static String GTASK_JSON_LAST_MODIFIED = "last_modified";
+
+    public final static String GTASK_JSON_LATEST_SYNC_POINT = "latest_sync_point";
+
+    public final static String GTASK_JSON_LIST_ID = "list_id";
+
+    public final static String GTASK_JSON_LISTS = "lists";
+
+    public final static String GTASK_JSON_NAME = "name";
+
+    public final static String GTASK_JSON_NEW_ID = "new_id";
+
+    public final static String GTASK_JSON_NOTES = "notes";
+
+    public final static String GTASK_JSON_PARENT_ID = "parent_id";
+
+    public final static String GTASK_JSON_PRIOR_SIBLING_ID = "prior_sibling_id";
+
+    public final static String GTASK_JSON_RESULTS = "results";
+
+    public final static String GTASK_JSON_SOURCE_LIST = "source_list";
+
+    public final static String GTASK_JSON_TASKS = "tasks";
+
+    public final static String GTASK_JSON_TYPE = "type";
+
+    public final static String GTASK_JSON_TYPE_GROUP = "GROUP";
+
+    public final static String GTASK_JSON_TYPE_TASK = "TASK";
+
+    public final static String GTASK_JSON_USER = "user";
+
+    public final static String MIUI_FOLDER_PREFFIX = "[MIUI_Notes]";
+
+    public final static String FOLDER_DEFAULT = "Default";
+
+    public final static String FOLDER_CALL_NOTE = "Call_Note";
+
+    public final static String FOLDER_META = "METADATA";
+
+    public final static String META_HEAD_GTASK_ID = "meta_gid";
+
+    public final static String META_HEAD_NOTE = "meta_note";
+
+    public final static String META_HEAD_DATA = "meta_data";
+
+    public final static String META_NOTE_NAME = "[META INFO] DON'T UPDATE AND DELETE";
+
+}

ceshi.txt

@@ -0,0 +1 @@
+测试代码

java/net/micode/notes/MainActivity.java

@@ -0,0 +1,24 @@
+package net.micode.notes;
+
+import android.os.Bundle;
+
+import androidx.activity.EdgeToEdge;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.core.graphics.Insets;
+import androidx.core.view.ViewCompat;
+import androidx.core.view.WindowInsetsCompat;
+
+public class MainActivity extends AppCompatActivity {
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        EdgeToEdge.enable(this);
+        setContentView(R.layout.activity_main);
+        ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main), (v, insets) -> {
+            Insets systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars());
+            v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom);
+            return insets;
+        });
+    }
+}

java/net/micode/notes/data/Contact.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了Contact类，主要用于实现根据电话号码获取对应联系人姓名的功能。它通过维护一个静态的HashMap作为缓存（sContactCache）来避免重复查询，利用安卓系统的ContentResolver结合特定的查询条件（CALLER_ID_SELECTION）从联系人数据提供者（Data.CONTENT_URI）中查找匹配电话号码的联系人姓名信息，若找到则存入缓存并返回，整体旨在提高获取联系人姓名操作的效率，优化在应用中频繁查询联系人相关信息的性能。
+函数分析
+getContact方法
+所属类：Contact
+功能：首先判断缓存HashMap（sContactCache）是否为null，若是则创建一个新的实例。接着检查传入的电话号码是否已存在于缓存中，若存在则直接从缓存获取并返回对应的联系人姓名。若不在缓存中，会先替换查询条件（CALLER_ID_SELECTION）中的占位符，将电话号码转换为适合查询的格式，然后通过ContentResolver发起查询，若游标不为null且能移动到第一条记录，则尝试获取联系人姓名，存入缓存后返回该姓名；若游标为null或者获取过程出现异常（捕获IndexOutOfBoundsException）则记录相应日志并返回null，用于根据给定的电话号码查找并返回对应的联系人姓名，同时利用缓存机制减少重复查询开销。
+ */
+
+package net.micode.notes.data;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.provider.ContactsContract.CommonDataKinds.Phone;
+import android.provider.ContactsContract.Data;
+import android.telephony.PhoneNumberUtils;
+import android.util.Log;
+
+import java.util.HashMap;
+
+public class Contact {
+    private static HashMap<String, String> sContactCache;
+    private static final String TAG = "Contact";
+
+    private static final String CALLER_ID_SELECTION = "PHONE_NUMBERS_EQUAL(" + Phone.NUMBER
+    + ",?) AND " + Data.MIMETYPE + "='" + Phone.CONTENT_ITEM_TYPE + "'"
+    + " AND " + Data.RAW_CONTACT_ID + " IN "
+            + "(SELECT raw_contact_id "
+            + " FROM phone_lookup"
+            + " WHERE min_match = '+')";
+
+    public static String getContact(Context context, String phoneNumber) {
+        if(sContactCache == null) {
+            sContactCache = new HashMap<String, String>();
+        }
+
+        if(sContactCache.containsKey(phoneNumber)) {
+            return sContactCache.get(phoneNumber);
+        }
+
+        String selection = CALLER_ID_SELECTION.replace("+",
+                PhoneNumberUtils.toCallerIDMinMatch(phoneNumber));
+        Cursor cursor = context.getContentResolver().query(
+                Data.CONTENT_URI,
+                new String [] { Phone.DISPLAY_NAME },
+                selection,
+                new String[] { phoneNumber },
+                null);
+
+        if (cursor != null && cursor.moveToFirst()) {
+            try {
+                String name = cursor.getString(0);
+                sContactCache.put(phoneNumber, name);
+                return name;
+            } catch (IndexOutOfBoundsException e) {
+                Log.e(TAG, " Cursor get string error " + e.toString());
+                return null;
+            } finally {
+                cursor.close();
+            }
+        } else {
+            Log.d(TAG, "No contact matched with number:" + phoneNumber);
+            return null;
+        }
+    }
+}

java/net/micode/notes/data/Notes.java

@@ -0,0 +1,300 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了Notes类，它主要起到对笔记相关的常量、接口以及内部类进行统一管理的作用，涵盖了笔记应用中涉及的各种类型定义（如笔记类型、部件类型等）、系统文件夹的标识、用于数据查询的Uri地址，以及针对笔记列和数据列相关属性的接口定义（包括各属性的数据类型说明），还有针对文本笔记和通话记录笔记的具体内部类定义（包含各自特有的属性和对应的Uri等），整体为整个笔记应用在数据存储、查询以及不同类型笔记处理等方面提供了规范且统一的常量与结构定义基础。
+函数分析
+常量相关：
+AUTHORITY：定义了内容提供器的授权字符串为"micode_notes"，用于在安卓系统中标识该应用对应的内容提供器，后续构建Uri等操作会依赖它来确定操作的数据来源。
+TYPE_NOTE、TYPE_FOLDER、TYPE_SYSTEM：分别代表笔记、文件夹、系统相关的类型标识常量，用于区分不同类型的存储对象，在数据库存储、查询以及业务逻辑中根据类型进行不同处理时会用到这些标识。
+ID_ROOT_FOLDER、ID_TEMPARAY_FOLDER、ID_CALL_RECORD_FOLDER、ID_TRASH_FOLER：定义了系统中不同功能文件夹的唯一标识常量，比如默认文件夹、临时文件夹、通话记录文件夹以及回收站文件夹等，方便在操作笔记与文件夹关联、移动等场景下通过这些固定标识来确定特定的文件夹。
+INTENT_EXTRA_ALERT_DATE、INTENT_EXTRA_BACKGROUND_ID 等：一系列的字符串常量，用于作为传递额外意图信息的键值，比如在不同组件间传递提醒日期、背景颜色ID、部件相关属性以及文件夹ID等信息时，以此作为标准的键来传递对应的值。
+TYPE_WIDGET_INVALIDE、TYPE_WIDGET_2X、TYPE_WIDGET_4X：定义了部件类型相关的常量，用于区分不同尺寸或者无效的部件类型，在涉及部件相关的业务逻辑（如笔记关联部件、部件显示等）中起到标识作用。
+DataConstants内部类相关：
+NOTE和CALL_NOTE：分别通过引用TextNote.CONTENT_ITEM_TYPE和CallNote.CONTENT_ITEM_TYPE，定义了代表普通笔记和通话记录笔记的MIME_TYPE常量，用于在数据处理过程中区分不同类型的笔记数据，比如根据MIME_TYPE进行数据解析、存储等操作时可以通过这两个常量来判断。
+CONTENT_NOTE_URI和CONTENT_DATA_URI：
+这两个Uri常量分别定义了用于查询所有笔记和文件夹以及查询数据的统一资源标识符，是通过content://协议结合授权字符串构建而成，在使用ContentResolver进行数据库查询等操作时，作为查询的目标地址，方便从对应的数据库表中获取相应的数据。
+NoteColumns接口相关：
+该接口定义了一系列与笔记列相关的属性常量，比如笔记的唯一ID、父ID、创建日期、修改日期、提醒日期、名称或内容、部件相关属性（ID、类型、背景颜色ID）、是否有附件、笔记数量、类型、同步ID、本地修改标识以及关联的Gtask ID、版本号等，明确了笔记表中各列的名称以及对应的数据类型，为数据库操作中对笔记表的增删改查等操作提供了统一的列名引用规范，便于代码的可读性和维护性。
+DataColumns接口相关：
+此接口定义了一系列针对数据列的属性常量，涵盖了数据行的唯一ID、MIME_TYPE、所属笔记的ID、创建日期、修改日期、内容以及多个通用数据列（DATA1 - DATA5，其含义根据MIME_TYPE特定）等，同样为数据库中数据相关表的操作提供了统一的列名和数据类型规范，在处理笔记附属数据（如文本、多媒体等不同类型数据）的存储、查询等操作时可依据这些常量进行准确的操作。
+TextNote内部类相关：
+定义了文本笔记相关的属性和Uri等信息，比如MODE属性用于表示文本是否处于清单模式，还有代表文本笔记的内容类型（CONTENT_TYPE）、内容项类型（CONTENT_ITEM_TYPE）以及对应的Uri（CONTENT_URI），在处理文本笔记相关的数据存储、查询以及与其他组件交互等业务场景中提供了具体的类型标识和操作地址等依据。
+CallNote内部类相关：
+针对通话记录笔记，定义了通话日期（CALL_DATE）、电话号码（PHONE_NUMBER）等特有属性，以及内容类型（CONTENT_TYPE）、内容项类型（CONTENT_ITEM_TYPE）和对应的Uri（CONTENT_URI），方便在处理通话记录笔记数据时进行特定属性的操作以及基于Uri的数据库查询等操作。
+ */
+
+package net.micode.notes.data;
+
+import android.net.Uri;
+public class Notes {
+    public static final String AUTHORITY = "micode_notes";
+    public static final String TAG = "Notes";
+    public static final int TYPE_NOTE     = 0;
+    public static final int TYPE_FOLDER   = 1;
+    public static final int TYPE_SYSTEM   = 2;
+
+    /**
+     * Following IDs are system folders' identifiers
+     * {@link Notes#ID_ROOT_FOLDER } is default folder
+     * {@link Notes#ID_TEMPARAY_FOLDER } is for notes belonging no folder
+     * {@link Notes#ID_CALL_RECORD_FOLDER} is to store call records
+     */
+    public static final int ID_ROOT_FOLDER = 0;
+    public static final int ID_TEMPARAY_FOLDER = -1;
+    public static final int ID_CALL_RECORD_FOLDER = -2;
+    public static final int ID_TRASH_FOLER = -3;
+
+    public static final String INTENT_EXTRA_ALERT_DATE = "net.micode.notes.alert_date";
+    public static final String INTENT_EXTRA_BACKGROUND_ID = "net.micode.notes.background_color_id";
+    public static final String INTENT_EXTRA_WIDGET_ID = "net.micode.notes.widget_id";
+    public static final String INTENT_EXTRA_WIDGET_TYPE = "net.micode.notes.widget_type";
+    public static final String INTENT_EXTRA_FOLDER_ID = "net.micode.notes.folder_id";
+    public static final String INTENT_EXTRA_CALL_DATE = "net.micode.notes.call_date";
+
+    public static final int TYPE_WIDGET_INVALIDE      = -1;
+    public static final int TYPE_WIDGET_2X            = 0;
+    public static final int TYPE_WIDGET_4X            = 1;
+
+    public static class DataConstants {
+        public static final String NOTE = TextNote.CONTENT_ITEM_TYPE;
+        public static final String CALL_NOTE = CallNote.CONTENT_ITEM_TYPE;
+    }
+
+    /**
+     * Uri to query all notes and folders
+     */
+    public static final Uri CONTENT_NOTE_URI = Uri.parse("content://" + AUTHORITY + "/note");
+
+    /**
+     * Uri to query data
+     */
+    public static final Uri CONTENT_DATA_URI = Uri.parse("content://" + AUTHORITY + "/data");
+
+    public interface NoteColumns {
+        /**
+         * The unique ID for a row
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String ID = "_id";
+
+        /**
+         * The parent's id for note or folder
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String PARENT_ID = "parent_id";
+
+        /**
+         * Created data for note or folder
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String CREATED_DATE = "created_date";
+
+        /**
+         * Latest modified date
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String MODIFIED_DATE = "modified_date";
+
+
+        /**
+         * Alert date
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String ALERTED_DATE = "alert_date";
+
+        /**
+         * Folder's name or text content of note
+         * <P> Type: TEXT </P>
+         */
+        public static final String SNIPPET = "snippet";
+
+        /**
+         * Note's widget id
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String WIDGET_ID = "widget_id";
+
+        /**
+         * Note's widget type
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String WIDGET_TYPE = "widget_type";
+
+        /**
+         * Note's background color's id
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String BG_COLOR_ID = "bg_color_id";
+
+        /**
+         * For text note, it doesn't has attachment, for multi-media
+         * note, it has at least one attachment
+         * <P> Type: INTEGER </P>
+         */
+        public static final String HAS_ATTACHMENT = "has_attachment";
+
+        /**
+         * Folder's count of notes
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String NOTES_COUNT = "notes_count";
+
+        /**
+         * The file type: folder or note
+         * <P> Type: INTEGER </P>
+         */
+        public static final String TYPE = "type";
+
+        /**
+         * The last sync id
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String SYNC_ID = "sync_id";
+
+        /**
+         * Sign to indicate local modified or not
+         * <P> Type: INTEGER </P>
+         */
+        public static final String LOCAL_MODIFIED = "local_modified";
+
+        /**
+         * Original parent id before moving into temporary folder
+         * <P> Type : INTEGER </P>
+         */
+        public static final String ORIGIN_PARENT_ID = "origin_parent_id";
+
+        /**
+         * The gtask id
+         * <P> Type : TEXT </P>
+         */
+        public static final String GTASK_ID = "gtask_id";
+
+        /**
+         * The version code
+         * <P> Type : INTEGER (long) </P>
+         */
+        public static final String VERSION = "version";
+    }
+
+    public interface DataColumns {
+        /**
+         * The unique ID for a row
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String ID = "_id";
+
+        /**
+         * The MIME type of the item represented by this row.
+         * <P> Type: Text </P>
+         */
+        public static final String MIME_TYPE = "mime_type";
+
+        /**
+         * The reference id to note that this data belongs to
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String NOTE_ID = "note_id";
+
+        /**
+         * Created data for note or folder
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String CREATED_DATE = "created_date";
+
+        /**
+         * Latest modified date
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String MODIFIED_DATE = "modified_date";
+
+        /**
+         * Data's content
+         * <P> Type: TEXT </P>
+         */
+        public static final String CONTENT = "content";
+
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * integer data type
+         * <P> Type: INTEGER </P>
+         */
+        public static final String DATA1 = "data1";
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * integer data type
+         * <P> Type: INTEGER </P>
+         */
+        public static final String DATA2 = "data2";
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * TEXT data type
+         * <P> Type: TEXT </P>
+         */
+        public static final String DATA3 = "data3";
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * TEXT data type
+         * <P> Type: TEXT </P>
+         */
+        public static final String DATA4 = "data4";
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * TEXT data type
+         * <P> Type: TEXT </P>
+         */
+        public static final String DATA5 = "data5";
+    }
+
+    public static final class TextNote implements DataColumns {
+        /**
+         * Mode to indicate the text in check list mode or not
+         * <P> Type: Integer 1:check list mode 0: normal mode </P>
+         */
+        public static final String MODE = DATA1;
+
+        public static final int MODE_CHECK_LIST = 1;
+
+        public static final String CONTENT_TYPE = "vnd.android.cursor.dir/text_note";
+
+        public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/text_note";
+
+        public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/text_note");
+    }
+
+    public static final class CallNote implements DataColumns {
+        /**
+         * Call date for this record
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String CALL_DATE = DATA1;
+
+        /**
+         * Phone number for this record
+         * <P> Type: TEXT </P>
+         */
+        public static final String PHONE_NUMBER = DATA3;
+
+        public static final String CONTENT_TYPE = "vnd.android.cursor.dir/call_note";
+
+        public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/call_note";
+
+        public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/call_note");
+    }
+}

java/net/micode/notes/data/NotesDatabaseHelper.java

@@ -0,0 +1,401 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了NotesDatabaseHelper类，它继承自SQLiteOpenHelper，是用于管理和操作笔记应用相关数据库的核心辅助类。主要负责数据库的创建（包括创建表结构、索引以及各类触发器等）、数据库版本升级等功能，通过一系列预定义的 SQL 语句来构建数据库环境，同时在版本升级时按照不同版本间的差异进行相应的表结构修改、新增列以及触发器重建等操作，以保证数据库能适配应用的不同版本需求，整体为笔记应用的数据持久化存储与管理提供了可靠的数据库层面支持。
+函数分析
+NotesDatabaseHelper类构造函数
+所属类：NotesDatabaseHelper
+功能：调用父类（SQLiteOpenHelper）的构造函数，传入应用上下文、数据库名称（固定为"note.db"）、游标工厂（这里传null）以及数据库版本号（固定为4），用于初始化数据库帮助类对象，为后续操作数据库做准备。
+createNoteTable方法
+所属类：NotesDatabaseHelper
+功能：在传入的SQLiteDatabase对象上执行创建笔记表（note表）的 SQL 语句（CREATE_NOTE_TABLE_SQL），接着调用reCreateNoteTableTriggers方法重建与笔记表相关的触发器，再调用createSystemFolder方法创建系统文件夹相关记录插入到笔记表中，最后记录日志表示笔记表已创建，用于完成创建笔记表以及相关初始化操作的功能。
+reCreateNoteTableTriggers方法
+所属类：NotesDatabaseHelper
+功能：先通过execSQL方法依次删除一系列已存在的与笔记表相关的触发器（如文件夹计数增减触发器、数据删除关联触发器等），然后再按照定义好的创建触发器的 SQL 语句（如NOTE_INCREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER等）重新创建这些触发器，用于在需要时重新构建笔记表相关的触发器逻辑，确保数据库操作时对应的触发机制正确生效。
+createSystemFolder方法
+所属类：NotesDatabaseHelper
+功能：通过ContentValues对象来设置不同系统文件夹（通话记录文件夹、根文件夹、临时文件夹、回收站文件夹）的相关属性（如ID、TYPE等），然后使用SQLiteDatabase的insert方法将这些系统文件夹记录插入到笔记表中，用于初始化创建系统文件夹相关的数据记录，完善笔记表初始数据结构。
+createDataTable方法
+所属类：NotesDatabaseHelper
+功能：在给定的SQLiteDatabase对象上执行创建数据表（data表）的 SQL 语句（CREATE_DATA_TABLE_SQL），接着调用reCreateDataTableTriggers方法重建与数据表相关的触发器，再执行创建数据表中note_id索引的 SQL 语句（CREATE_DATA_NOTE_ID_INDEX_SQL），最后记录日志表示数据表已创建，用于完成创建数据表以及相关初始化操作的功能。
+reCreateDataTableTriggers方法
+所属类：NotesDatabaseHelper
+功能：先删除已存在的与数据表中笔记内容更新相关的触发器（插入、更新、删除操作对应的触发器），然后再按照定义好的创建这些触发器的 SQL 语句（如DATA_UPDATE_NOTE_CONTENT_ON_INSERT_TRIGGER等）重新创建它们，用于在数据表操作时正确触发相应的笔记内容更新逻辑，保证数据一致性。
+getInstance方法
+所属类：NotesDatabaseHelper
+功能：采用单例模式，通过同步锁机制判断类的实例（mInstance）是否为null，若为null则创建一个新的NotesDatabaseHelper对象并赋值给mInstance，最后返回该实例，用于保证整个应用中只有一个数据库帮助类实例，方便在不同地方统一操作数据库，避免多次创建数据库连接等资源浪费。
+onCreate方法
+所属类：NotesDatabaseHelper
+功能：重写了父类（SQLiteOpenHelper）的onCreate方法，在数据库首次创建时被调用，内部调用createNoteTable和createDataTable方法分别创建笔记表和数据表，用于初始化数据库的基础表结构等相关内容。
+onUpgrade方法
+所属类：NotesDatabaseHelper
+功能：重写了父类的onUpgrade方法，用于处理数据库版本升级的逻辑。根据旧版本号（oldVersion）与新版本号（newVersion）的对比情况，执行不同的升级操作，比如从版本1升级到版本2时调用upgradeToV2方法，从版本2升级到版本3时调用upgradeToV3方法等，同时根据需要决定是否重建相关的触发器，若最终旧版本号和新版本号不一致则抛出异常，表示升级失败，整体实现了按照应用不同版本需求对数据库结构进行相应调整的功能。
+upgradeToV2方法
+所属类：NotesDatabaseHelper
+功能：在数据库从版本1升级到版本2时被调用，先删除已存在的笔记表和数据表，然后重新调用createNoteTable和createDataTable方法创建新的表结构，用于完成特定版本间数据库表结构的重建升级操作。
+upgradeToV3方法
+所属类：NotesDatabaseHelper
+功能：在数据库从版本2升级到版本3时被调用，执行以下操作：先删除一些不再使用的触发器，接着通过ALTER TABLE语句为笔记表添加一个用于存储Gtask ID的新列，最后创建回收站系统文件夹相关记录插入到笔记表中，用于实现版本2到版本3对应的数据库结构和功能调整。
+upgradeToV4方法
+所属类：NotesDatabaseHelper
+功能：在数据库从版本3升级到版本4时被调用，通过ALTER TABLE语句为笔记表添加一个版本号（VERSION）列，并设置默认值为0，用于完成版本3到版本4的数据库结构升级，满足对应版本应用对数据库的要求。
+ */
+
+package net.micode.notes.data;
+
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+import android.util.Log;
+
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.DataConstants;
+import net.micode.notes.data.Notes.NoteColumns;
+
+
+public class NotesDatabaseHelper extends SQLiteOpenHelper {
+    private static final String DB_NAME = "note.db";
+
+    private static final int DB_VERSION = 4;
+
+    public interface TABLE {
+        public static final String NOTE = "note";
+
+        public static final String DATA = "data";
+    }
+
+    private static final String TAG = "NotesDatabaseHelper";
+
+    private static NotesDatabaseHelper mInstance;
+
+    private static final String CREATE_NOTE_TABLE_SQL =
+        "CREATE TABLE " + TABLE.NOTE + "(" +
+            NoteColumns.ID + " INTEGER PRIMARY KEY," +
+            NoteColumns.PARENT_ID + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.ALERTED_DATE + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.BG_COLOR_ID + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.CREATED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," +
+            NoteColumns.HAS_ATTACHMENT + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.MODIFIED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," +
+            NoteColumns.NOTES_COUNT + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.SNIPPET + " TEXT NOT NULL DEFAULT ''," +
+            NoteColumns.TYPE + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.WIDGET_ID + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.WIDGET_TYPE + " INTEGER NOT NULL DEFAULT -1," +
+            NoteColumns.SYNC_ID + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.LOCAL_MODIFIED + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.ORIGIN_PARENT_ID + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.GTASK_ID + " TEXT NOT NULL DEFAULT ''," +
+            NoteColumns.VERSION + " INTEGER NOT NULL DEFAULT 0" +
+        ")";
+
+    private static final String CREATE_DATA_TABLE_SQL =
+        "CREATE TABLE " + TABLE.DATA + "(" +
+            DataColumns.ID + " INTEGER PRIMARY KEY," +
+            DataColumns.MIME_TYPE + " TEXT NOT NULL," +
+            DataColumns.NOTE_ID + " INTEGER NOT NULL DEFAULT 0," +
+            NoteColumns.CREATED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," +
+            NoteColumns.MODIFIED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," +
+            DataColumns.CONTENT + " TEXT NOT NULL DEFAULT ''," +
+            DataColumns.DATA1 + " INTEGER," +
+            DataColumns.DATA2 + " INTEGER," +
+            DataColumns.DATA3 + " TEXT NOT NULL DEFAULT ''," +
+            DataColumns.DATA4 + " TEXT NOT NULL DEFAULT ''," +
+            DataColumns.DATA5 + " TEXT NOT NULL DEFAULT ''" +
+        ")";
+
+    private static final String CREATE_DATA_NOTE_ID_INDEX_SQL =
+        "CREATE INDEX IF NOT EXISTS note_id_index ON " +
+        TABLE.DATA + "(" + DataColumns.NOTE_ID + ");";
+
+    /**
+     * Increase folder's note count when move note to the folder
+     */
+    private static final String NOTE_INCREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER =
+        "CREATE TRIGGER increase_folder_count_on_update "+
+        " AFTER UPDATE OF " + NoteColumns.PARENT_ID + " ON " + TABLE.NOTE +
+        " BEGIN " +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + " + 1" +
+        "  WHERE " + NoteColumns.ID + "=new." + NoteColumns.PARENT_ID + ";" +
+        " END";
+
+    /**
+     * Decrease folder's note count when move note from folder
+     */
+    private static final String NOTE_DECREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER =
+        "CREATE TRIGGER decrease_folder_count_on_update " +
+        " AFTER UPDATE OF " + NoteColumns.PARENT_ID + " ON " + TABLE.NOTE +
+        " BEGIN " +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + "-1" +
+        "  WHERE " + NoteColumns.ID + "=old." + NoteColumns.PARENT_ID +
+        "  AND " + NoteColumns.NOTES_COUNT + ">0" + ";" +
+        " END";
+
+    /**
+     * Increase folder's note count when insert new note to the folder
+     */
+    private static final String NOTE_INCREASE_FOLDER_COUNT_ON_INSERT_TRIGGER =
+        "CREATE TRIGGER increase_folder_count_on_insert " +
+        " AFTER INSERT ON " + TABLE.NOTE +
+        " BEGIN " +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + " + 1" +
+        "  WHERE " + NoteColumns.ID + "=new." + NoteColumns.PARENT_ID + ";" +
+        " END";
+
+    /**
+     * Decrease folder's note count when delete note from the folder
+     */
+    private static final String NOTE_DECREASE_FOLDER_COUNT_ON_DELETE_TRIGGER =
+        "CREATE TRIGGER decrease_folder_count_on_delete " +
+        " AFTER DELETE ON " + TABLE.NOTE +
+        " BEGIN " +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + "-1" +
+        "  WHERE " + NoteColumns.ID + "=old." + NoteColumns.PARENT_ID +
+        "  AND " + NoteColumns.NOTES_COUNT + ">0;" +
+        " END";
+
+    /**
+     * Update note's content when insert data with type {@link DataConstants#NOTE}
+     */
+    private static final String DATA_UPDATE_NOTE_CONTENT_ON_INSERT_TRIGGER =
+        "CREATE TRIGGER update_note_content_on_insert " +
+        " AFTER INSERT ON " + TABLE.DATA +
+        " WHEN new." + DataColumns.MIME_TYPE + "='" + DataConstants.NOTE + "'" +
+        " BEGIN" +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.SNIPPET + "=new." + DataColumns.CONTENT +
+        "  WHERE " + NoteColumns.ID + "=new." + DataColumns.NOTE_ID + ";" +
+        " END";
+
+    /**
+     * Update note's content when data with {@link DataConstants#NOTE} type has changed
+     */
+    private static final String DATA_UPDATE_NOTE_CONTENT_ON_UPDATE_TRIGGER =
+        "CREATE TRIGGER update_note_content_on_update " +
+        " AFTER UPDATE ON " + TABLE.DATA +
+        " WHEN old." + DataColumns.MIME_TYPE + "='" + DataConstants.NOTE + "'" +
+        " BEGIN" +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.SNIPPET + "=new." + DataColumns.CONTENT +
+        "  WHERE " + NoteColumns.ID + "=new." + DataColumns.NOTE_ID + ";" +
+        " END";
+
+    /**
+     * Update note's content when data with {@link DataConstants#NOTE} type has deleted
+     */
+    private static final String DATA_UPDATE_NOTE_CONTENT_ON_DELETE_TRIGGER =
+        "CREATE TRIGGER update_note_content_on_delete " +
+        " AFTER delete ON " + TABLE.DATA +
+        " WHEN old." + DataColumns.MIME_TYPE + "='" + DataConstants.NOTE + "'" +
+        " BEGIN" +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.SNIPPET + "=''" +
+        "  WHERE " + NoteColumns.ID + "=old." + DataColumns.NOTE_ID + ";" +
+        " END";
+
+    /**
+     * Delete datas belong to note which has been deleted
+     */
+    private static final String NOTE_DELETE_DATA_ON_DELETE_TRIGGER =
+        "CREATE TRIGGER delete_data_on_delete " +
+        " AFTER DELETE ON " + TABLE.NOTE +
+        " BEGIN" +
+        "  DELETE FROM " + TABLE.DATA +
+        "   WHERE " + DataColumns.NOTE_ID + "=old." + NoteColumns.ID + ";" +
+        " END";
+
+    /**
+     * Delete notes belong to folder which has been deleted
+     */
+    private static final String FOLDER_DELETE_NOTES_ON_DELETE_TRIGGER =
+        "CREATE TRIGGER folder_delete_notes_on_delete " +
+        " AFTER DELETE ON " + TABLE.NOTE +
+        " BEGIN" +
+        "  DELETE FROM " + TABLE.NOTE +
+        "   WHERE " + NoteColumns.PARENT_ID + "=old." + NoteColumns.ID + ";" +
+        " END";
+
+    /**
+     * Move notes belong to folder which has been moved to trash folder
+     */
+    private static final String FOLDER_MOVE_NOTES_ON_TRASH_TRIGGER =
+        "CREATE TRIGGER folder_move_notes_on_trash " +
+        " AFTER UPDATE ON " + TABLE.NOTE +
+        " WHEN new." + NoteColumns.PARENT_ID + "=" + Notes.ID_TRASH_FOLER +
+        " BEGIN" +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.PARENT_ID + "=" + Notes.ID_TRASH_FOLER +
+        "  WHERE " + NoteColumns.PARENT_ID + "=old." + NoteColumns.ID + ";" +
+        " END";
+
+    public NotesDatabaseHelper(Context context) {
+        super(context, DB_NAME, null, DB_VERSION);
+    }
+
+    public void createNoteTable(SQLiteDatabase db) {
+        db.execSQL(CREATE_NOTE_TABLE_SQL);
+        reCreateNoteTableTriggers(db);
+        createSystemFolder(db);
+        Log.d(TAG, "note table has been created");
+    }
+
+    private void reCreateNoteTableTriggers(SQLiteDatabase db) {
+        db.execSQL("DROP TRIGGER IF EXISTS increase_folder_count_on_update");
+        db.execSQL("DROP TRIGGER IF EXISTS decrease_folder_count_on_update");
+        db.execSQL("DROP TRIGGER IF EXISTS decrease_folder_count_on_delete");
+        db.execSQL("DROP TRIGGER IF EXISTS delete_data_on_delete");
+        db.execSQL("DROP TRIGGER IF EXISTS increase_folder_count_on_insert");
+        db.execSQL("DROP TRIGGER IF EXISTS folder_delete_notes_on_delete");
+        db.execSQL("DROP TRIGGER IF EXISTS folder_move_notes_on_trash");
+
+        db.execSQL(NOTE_INCREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER);
+        db.execSQL(NOTE_DECREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER);
+        db.execSQL(NOTE_DECREASE_FOLDER_COUNT_ON_DELETE_TRIGGER);
+        db.execSQL(NOTE_DELETE_DATA_ON_DELETE_TRIGGER);
+        db.execSQL(NOTE_INCREASE_FOLDER_COUNT_ON_INSERT_TRIGGER);
+        db.execSQL(FOLDER_DELETE_NOTES_ON_DELETE_TRIGGER);
+        db.execSQL(FOLDER_MOVE_NOTES_ON_TRASH_TRIGGER);
+    }
+
+    private void createSystemFolder(SQLiteDatabase db) {
+        ContentValues values = new ContentValues();
+
+        /**
+         * call record foler for call notes
+         */
+        values.put(NoteColumns.ID, Notes.ID_CALL_RECORD_FOLDER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+
+        /**
+         * root folder which is default folder
+         */
+        values.clear();
+        values.put(NoteColumns.ID, Notes.ID_ROOT_FOLDER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+
+        /**
+         * temporary folder which is used for moving note
+         */
+        values.clear();
+        values.put(NoteColumns.ID, Notes.ID_TEMPARAY_FOLDER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+
+        /**
+         * create trash folder
+         */
+        values.clear();
+        values.put(NoteColumns.ID, Notes.ID_TRASH_FOLER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+    }
+
+    public void createDataTable(SQLiteDatabase db) {
+        db.execSQL(CREATE_DATA_TABLE_SQL);
+        reCreateDataTableTriggers(db);
+        db.execSQL(CREATE_DATA_NOTE_ID_INDEX_SQL);
+        Log.d(TAG, "data table has been created");
+    }
+
+    private void reCreateDataTableTriggers(SQLiteDatabase db) {
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_insert");
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_update");
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_delete");
+
+        db.execSQL(DATA_UPDATE_NOTE_CONTENT_ON_INSERT_TRIGGER);
+        db.execSQL(DATA_UPDATE_NOTE_CONTENT_ON_UPDATE_TRIGGER);
+        db.execSQL(DATA_UPDATE_NOTE_CONTENT_ON_DELETE_TRIGGER);
+    }
+
+    static synchronized NotesDatabaseHelper getInstance(Context context) {
+        if (mInstance == null) {
+            mInstance = new NotesDatabaseHelper(context);
+        }
+        return mInstance;
+    }
+
+    @Override
+    public void onCreate(SQLiteDatabase db) {
+        createNoteTable(db);
+        createDataTable(db);
+    }
+
+    @Override
+    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
+        boolean reCreateTriggers = false;
+        boolean skipV2 = false;
+
+        if (oldVersion == 1) {
+            upgradeToV2(db);
+            skipV2 = true; // this upgrade including the upgrade from v2 to v3
+            oldVersion++;
+        }
+
+        if (oldVersion == 2 && !skipV2) {
+            upgradeToV3(db);
+            reCreateTriggers = true;
+            oldVersion++;
+        }
+
+        if (oldVersion == 3) {
+            upgradeToV4(db);
+            oldVersion++;
+        }
+
+        if (reCreateTriggers) {
+            reCreateNoteTableTriggers(db);
+            reCreateDataTableTriggers(db);
+        }
+
+        if (oldVersion != newVersion) {
+            throw new IllegalStateException("Upgrade notes database to version " + newVersion
+                    + "fails");
+        }
+    }
+
+    private void upgradeToV2(SQLiteDatabase db) {
+        db.execSQL("DROP TABLE IF EXISTS " + TABLE.NOTE);
+        db.execSQL("DROP TABLE IF EXISTS " + TABLE.DATA);
+        createNoteTable(db);
+        createDataTable(db);
+    }
+
+    private void upgradeToV3(SQLiteDatabase db) {
+        // drop unused triggers
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_modified_date_on_insert");
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_modified_date_on_delete");
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_modified_date_on_update");
+        // add a column for gtask id
+        db.execSQL("ALTER TABLE " + TABLE.NOTE + " ADD COLUMN " + NoteColumns.GTASK_ID
+                + " TEXT NOT NULL DEFAULT ''");
+        // add a trash system folder
+        ContentValues values = new ContentValues();
+        values.put(NoteColumns.ID, Notes.ID_TRASH_FOLER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+    }
+
+    private void upgradeToV4(SQLiteDatabase db) {
+        db.execSQL("ALTER TABLE " + TABLE.NOTE + " ADD COLUMN " + NoteColumns.VERSION
+                + " INTEGER NOT NULL DEFAULT 0");
+    }
+}

java/net/micode/notes/data/NotesProvider.java

@@ -0,0 +1,346 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了NotesProvider类，它继承自ContentProvider，是安卓应用中用于在不同组件间共享数据的重要组件，在笔记应用里充当数据提供者的角色。通过UriMatcher对不同的Uri进行匹配，以此来区分是对笔记表（note表）、数据表（data表）进行查询、插入、删除、更新等操作，还是处理搜索及搜索建议相关的逻辑，并且在操作数据后会根据情况发送数据变更通知，以保证相关组件能及时知晓数据的变化，整体实现了数据在应用内的统一管理与共享交互功能。
+函数分析
+NotesProvider类构造函数相关（静态代码块部分）
+所属类：NotesProvider
+功能：在静态代码块中初始化UriMatcher对象（mMatcher），向其中添加不同的Uri匹配规则，涵盖了笔记表、数据表、搜索以及搜索建议对应的Uri模式，例如匹配笔记表的Uri（"note"）对应URI_NOTE，匹配笔记表中单个记录的Uri（"note/#"）对应URI_NOTE_ITEM等，用于后续根据传入的Uri准确判断操作类型及对应的表。
+onCreate方法
+所属类：NotesProvider
+功能：重写了父类（ContentProvider）的onCreate方法，在内容提供者被创建时调用，通过NotesDatabaseHelper的单例模式获取数据库帮助类实例（mHelper），并返回true表示创建成功，用于初始化与数据库相关的操作对象，为后续数据库操作做准备。
+query方法
+所属类：NotesProvider
+功能：重写了父类的query方法，用于处理数据查询操作。首先获取可读数据库对象，然后根据UriMatcher对传入Uri的匹配结果分情况处理：
+若匹配到URI_NOTE，则对笔记表执行查询操作；若匹配到URI_NOTE_ITEM，则先获取Uri路径中的记录ID，再对笔记表中指定ID的记录进行查询。
+对于URI_DATA和URI_DATA_ITEM，类似地分别对数据表进行全表查询以及对数据表中指定ID的记录查询，查询时会结合传入的投影（projection）、选择条件（selection）等参数构建查询语句。
+当匹配到URI_SEARCH或URI_SEARCH_SUGGEST时，先获取搜索字符串，若为空则返回null，否则格式化搜索字符串后执行自定义的搜索查询语句（NOTES_SNIPPET_SEARCH_QUERY）获取搜索结果游标。最后若游标不为null，设置其通知Uri以便数据变化时能收到通知，最终返回游标用于获取查询到的数据，整体实现了根据不同Uri进行对应数据查询的功能。
+insert方法
+所属类：NotesProvider
+功能：重写了父类的insert方法，用于处理数据插入操作。获取可写数据库对象后，根据UriMatcher对传入Uri的匹配结果分情况插入数据：
+若匹配到URI_NOTE，则向笔记表插入数据并记录插入的记录ID（noteId）。
+若匹配到URI_DATA，先获取所属笔记ID（若不存在则记录日志提示错误数据格式），再向数据表插入数据并记录插入的记录ID（dataId）。插入成功后，根据插入的ID是否大于0，分别向笔记表对应的ContentUri（Notes.CONTENT_NOTE_URI）和数据表对应的ContentUri（Notes.CONTENT_DATA_URI）发送数据变更通知，最后返回插入数据后对应Uri（通过ContentUris.withAppendedId构建），整体实现了向不同表插入数据并发送相应通知的功能。
+delete方法
+所属类：NotesProvider
+功能：重写了父类的delete方法，用于处理数据删除操作。获取可写数据库对象后，按照UriMatcher对传入Uri的匹配结果分情况删除数据：
+对于URI_NOTE，添加额外条件确保ID大于0（避免删除系统文件夹等情况）后删除笔记表中的记录。
+对于URI_NOTE_ITEM，获取Uri路径中的记录ID，判断ID合法（大于0）后删除对应笔记记录。
+对于URI_DATA和URI_DATA_ITEM，分别删除数据表中的记录以及数据表中指定ID的记录，同时标记是否删除的数据表相关（deleteData变量）。若删除的记录数大于0，根据是否与数据表相关向相应的Uri（笔记表Uri或操作对应的Uri）发送数据变更通知，最后返回删除的记录数量，整体实现了按不同Uri删除对应数据并发送通知的功能。
+update方法
+所属类：NotesProvider
+功能：重写了父类的update方法，用于处理数据更新操作。获取可写数据库对象后，依据UriMatcher对传入Uri的匹配结果分情况更新数据：
+对于URI_NOTE和URI_NOTE_ITEM，分别更新笔记表中的记录以及笔记表中指定ID的记录，更新前会调用increaseNoteVersion方法增加笔记版本号，然后执行更新操作并根据更新的记录数判断是否发送数据变更通知（向笔记表Uri或操作对应的Uri）。
+对于URI_DATA和URI_DATA_ITEM，类似地更新数据表中的记录以及数据表中指定ID的记录，并标记是否更新的数据表相关（updateData变量），根据更新记录数情况发送相应的通知，最后返回更新的记录数量，整体实现了按不同Uri更新对应数据并发送通知的功能。
+parseSelection方法
+所属类：NotesProvider
+功能：接收一个选择条件字符串（selection），判断其不为空时，在其前后添加" AND ("和")"，用于将传入的选择条件和已有的查询条件进行合理拼接，辅助其他数据库操作方法构建完整准确的查询、删除、更新等操作的条件语句。
+increaseNoteVersion方法
+所属类：NotesProvider
+功能：构建一个用于更新笔记表中版本号（NoteColumns.VERSION）的SQL语句，根据传入的笔记ID（id）以及选择条件（selection）、选择条件参数（selectionArgs）来确定WHERE子句的内容，然后通过数据库帮助类获取可写数据库对象并执行该SQL语句，用于在更新笔记相关数据时增加笔记的版本号，保证数据版本管理的一致性。
+getType方法
+所属类：NotesProvider
+功能：重写了父类的getType方法，目前方法体为空，按照ContentProvider规范，该方法应该返回对应Uri所代表的数据的MIME类型，不过此处尚未实现具体逻辑，可能需要根据实际需求补充代码来准确返回不同Uri对应的数据类型信息。
+
+ */
+
+package net.micode.notes.data;
+
+
+import android.app.SearchManager;
+import android.content.ContentProvider;
+import android.content.ContentUris;
+import android.content.ContentValues;
+import android.content.Intent;
+import android.content.UriMatcher;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.net.Uri;
+import android.text.TextUtils;
+import android.util.Log;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.data.NotesDatabaseHelper.TABLE;
+
+
+public class NotesProvider extends ContentProvider {
+    private static final UriMatcher mMatcher;
+
+    private NotesDatabaseHelper mHelper;
+
+    private static final String TAG = "NotesProvider";
+
+    private static final int URI_NOTE            = 1;
+    private static final int URI_NOTE_ITEM       = 2;
+    private static final int URI_DATA            = 3;
+    private static final int URI_DATA_ITEM       = 4;
+
+    private static final int URI_SEARCH          = 5;
+    private static final int URI_SEARCH_SUGGEST  = 6;
+
+    static {
+        mMatcher = new UriMatcher(UriMatcher.NO_MATCH);
+        mMatcher.addURI(Notes.AUTHORITY, "note", URI_NOTE);
+        mMatcher.addURI(Notes.AUTHORITY, "note/#", URI_NOTE_ITEM);
+        mMatcher.addURI(Notes.AUTHORITY, "data", URI_DATA);
+        mMatcher.addURI(Notes.AUTHORITY, "data/#", URI_DATA_ITEM);
+        mMatcher.addURI(Notes.AUTHORITY, "search", URI_SEARCH);
+        mMatcher.addURI(Notes.AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY, URI_SEARCH_SUGGEST);
+        mMatcher.addURI(Notes.AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY + "/*", URI_SEARCH_SUGGEST);
+    }
+
+    /**
+     * x'0A' represents the '\n' character in sqlite. For title and content in the search result,
+     * we will trim '\n' and white space in order to show more information.
+     */
+    private static final String NOTES_SEARCH_PROJECTION = NoteColumns.ID + ","
+        + NoteColumns.ID + " AS " + SearchManager.SUGGEST_COLUMN_INTENT_EXTRA_DATA + ","
+        + "TRIM(REPLACE(" + NoteColumns.SNIPPET + ", x'0A','')) AS " + SearchManager.SUGGEST_COLUMN_TEXT_1 + ","
+        + "TRIM(REPLACE(" + NoteColumns.SNIPPET + ", x'0A','')) AS " + SearchManager.SUGGEST_COLUMN_TEXT_2 + ","
+        + R.drawable.search_result + " AS " + SearchManager.SUGGEST_COLUMN_ICON_1 + ","
+        + "'" + Intent.ACTION_VIEW + "' AS " + SearchManager.SUGGEST_COLUMN_INTENT_ACTION + ","
+        + "'" + Notes.TextNote.CONTENT_TYPE + "' AS " + SearchManager.SUGGEST_COLUMN_INTENT_DATA;
+
+    private static String NOTES_SNIPPET_SEARCH_QUERY = "SELECT " + NOTES_SEARCH_PROJECTION
+        + " FROM " + TABLE.NOTE
+        + " WHERE " + NoteColumns.SNIPPET + " LIKE ?"
+        + " AND " + NoteColumns.PARENT_ID + "<>" + Notes.ID_TRASH_FOLER
+        + " AND " + NoteColumns.TYPE + "=" + Notes.TYPE_NOTE;
+
+    @Override
+    public boolean onCreate() {
+        mHelper = NotesDatabaseHelper.getInstance(getContext());
+        return true;
+    }
+
+    @Override
+    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
+            String sortOrder) {
+        Cursor c = null;
+        SQLiteDatabase db = mHelper.getReadableDatabase();
+        String id = null;
+        switch (mMatcher.match(uri)) {
+            case URI_NOTE:
+                c = db.query(TABLE.NOTE, projection, selection, selectionArgs, null, null,
+                        sortOrder);
+                break;
+            case URI_NOTE_ITEM:
+                id = uri.getPathSegments().get(1);
+                c = db.query(TABLE.NOTE, projection, NoteColumns.ID + "=" + id
+                        + parseSelection(selection), selectionArgs, null, null, sortOrder);
+                break;
+            case URI_DATA:
+                c = db.query(TABLE.DATA, projection, selection, selectionArgs, null, null,
+                        sortOrder);
+                break;
+            case URI_DATA_ITEM:
+                id = uri.getPathSegments().get(1);
+                c = db.query(TABLE.DATA, projection, DataColumns.ID + "=" + id
+                        + parseSelection(selection), selectionArgs, null, null, sortOrder);
+                break;
+            case URI_SEARCH:
+            case URI_SEARCH_SUGGEST:
+                if (sortOrder != null || projection != null) {
+                    throw new IllegalArgumentException(
+                            "do not specify sortOrder, selection, selectionArgs, or projection" + "with this query");
+                }
+
+                String searchString = null;
+                if (mMatcher.match(uri) == URI_SEARCH_SUGGEST) {
+                    if (uri.getPathSegments().size() > 1) {
+                        searchString = uri.getPathSegments().get(1);
+                    }
+                } else {
+                    searchString = uri.getQueryParameter("pattern");
+                }
+
+                if (TextUtils.isEmpty(searchString)) {
+                    return null;
+                }
+
+                try {
+                    searchString = String.format("%%%s%%", searchString);
+                    c = db.rawQuery(NOTES_SNIPPET_SEARCH_QUERY,
+                            new String[] { searchString });
+                } catch (IllegalStateException ex) {
+                    Log.e(TAG, "got exception: " + ex.toString());
+                }
+                break;
+            default:
+                throw new IllegalArgumentException("Unknown URI " + uri);
+        }
+        if (c != null) {
+            c.setNotificationUri(getContext().getContentResolver(), uri);
+        }
+        return c;
+    }
+
+    @Override
+    public Uri insert(Uri uri, ContentValues values) {
+        SQLiteDatabase db = mHelper.getWritableDatabase();
+        long dataId = 0, noteId = 0, insertedId = 0;
+        switch (mMatcher.match(uri)) {
+            case URI_NOTE:
+                insertedId = noteId = db.insert(TABLE.NOTE, null, values);
+                break;
+            case URI_DATA:
+                if (values.containsKey(DataColumns.NOTE_ID)) {
+                    noteId = values.getAsLong(DataColumns.NOTE_ID);
+                } else {
+                    Log.d(TAG, "Wrong data format without note id:" + values.toString());
+                }
+                insertedId = dataId = db.insert(TABLE.DATA, null, values);
+                break;
+            default:
+                throw new IllegalArgumentException("Unknown URI " + uri);
+        }
+        // Notify the note uri
+        if (noteId > 0) {
+            getContext().getContentResolver().notifyChange(
+                    ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId), null);
+        }
+
+        // Notify the data uri
+        if (dataId > 0) {
+            getContext().getContentResolver().notifyChange(
+                    ContentUris.withAppendedId(Notes.CONTENT_DATA_URI, dataId), null);
+        }
+
+        return ContentUris.withAppendedId(uri, insertedId);
+    }
+
+    @Override
+    public int delete(Uri uri, String selection, String[] selectionArgs) {
+        int count = 0;
+        String id = null;
+        SQLiteDatabase db = mHelper.getWritableDatabase();
+        boolean deleteData = false;
+        switch (mMatcher.match(uri)) {
+            case URI_NOTE:
+                selection = "(" + selection + ") AND " + NoteColumns.ID + ">0 ";
+                count = db.delete(TABLE.NOTE, selection, selectionArgs);
+                break;
+            case URI_NOTE_ITEM:
+                id = uri.getPathSegments().get(1);
+                /**
+                 * ID that smaller than 0 is system folder which is not allowed to
+                 * trash
+                 */
+                long noteId = Long.valueOf(id);
+                if (noteId <= 0) {
+                    break;
+                }
+                count = db.delete(TABLE.NOTE,
+                        NoteColumns.ID + "=" + id + parseSelection(selection), selectionArgs);
+                break;
+            case URI_DATA:
+                count = db.delete(TABLE.DATA, selection, selectionArgs);
+                deleteData = true;
+                break;
+            case URI_DATA_ITEM:
+                id = uri.getPathSegments().get(1);
+                count = db.delete(TABLE.DATA,
+                        DataColumns.ID + "=" + id + parseSelection(selection), selectionArgs);
+                deleteData = true;
+                break;
+            default:
+                throw new IllegalArgumentException("Unknown URI " + uri);
+        }
+        if (count > 0) {
+            if (deleteData) {
+                getContext().getContentResolver().notifyChange(Notes.CONTENT_NOTE_URI, null);
+            }
+            getContext().getContentResolver().notifyChange(uri, null);
+        }
+        return count;
+    }
+
+    @Override
+    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
+        int count = 0;
+        String id = null;
+        SQLiteDatabase db = mHelper.getWritableDatabase();
+        boolean updateData = false;
+        switch (mMatcher.match(uri)) {
+            case URI_NOTE:
+                increaseNoteVersion(-1, selection, selectionArgs);
+                count = db.update(TABLE.NOTE, values, selection, selectionArgs);
+                break;
+            case URI_NOTE_ITEM:
+                id = uri.getPathSegments().get(1);
+                increaseNoteVersion(Long.valueOf(id), selection, selectionArgs);
+                count = db.update(TABLE.NOTE, values, NoteColumns.ID + "=" + id
+                        + parseSelection(selection), selectionArgs);
+                break;
+            case URI_DATA:
+                count = db.update(TABLE.DATA, values, selection, selectionArgs);
+                updateData = true;
+                break;
+            case URI_DATA_ITEM:
+                id = uri.getPathSegments().get(1);
+                count = db.update(TABLE.DATA, values, DataColumns.ID + "=" + id
+                        + parseSelection(selection), selectionArgs);
+                updateData = true;
+                break;
+            default:
+                throw new IllegalArgumentException("Unknown URI " + uri);
+        }
+
+        if (count > 0) {
+            if (updateData) {
+                getContext().getContentResolver().notifyChange(Notes.CONTENT_NOTE_URI, null);
+            }
+            getContext().getContentResolver().notifyChange(uri, null);
+        }
+        return count;
+    }
+
+    private String parseSelection(String selection) {
+        return (!TextUtils.isEmpty(selection) ? " AND (" + selection + ')' : "");
+    }
+
+    private void increaseNoteVersion(long id, String selection, String[] selectionArgs) {
+        StringBuilder sql = new StringBuilder(120);
+        sql.append("UPDATE ");
+        sql.append(TABLE.NOTE);
+        sql.append(" SET ");
+        sql.append(NoteColumns.VERSION);
+        sql.append("=" + NoteColumns.VERSION + "+1 ");
+
+        if (id > 0 || !TextUtils.isEmpty(selection)) {
+            sql.append(" WHERE ");
+        }
+        if (id > 0) {
+            sql.append(NoteColumns.ID + "=" + String.valueOf(id));
+        }
+        if (!TextUtils.isEmpty(selection)) {
+            String selectString = id > 0 ? parseSelection(selection) : selection;
+            for (String args : selectionArgs) {
+                selectString = selectString.replaceFirst("\\?", args);
+            }
+            sql.append(selectString);
+        }
+
+        mHelper.getWritableDatabase().execSQL(sql.toString());
+    }
+
+    @Override
+    public String getType(Uri uri) {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+}

java/net/micode/notes/gtask/data/MetaData.java

@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了MetaData类，它继承自Task类，主要用于处理与元数据相关的特定逻辑，聚焦在关联 GTask 的相关标识（通过mRelatedGid）以及对元数据信息的存储、获取和相关操作的控制上。类中提供了设置元数据的方法，同时重写了父类的一些方法，像判断是否值得保存以及根据远程 JSON 数据设置内容等方法，不过也限制了部分方法（如设置本地 JSON 内容、获取本地 JSON 内容以及获取同步操作等方法）不能被调用，整体体现了对元数据这种特定数据在应用特定业务场景下的特殊处理逻辑。
+函数分析
+setMeta方法
+所属类：MetaData
+功能：尝试将传入的gid（关联的 GTask 标识）添加到给定的JSONObject（元数据信息）中指定的键（GTaskStringUtils.META_HEAD_GTASK_ID）下，若添加过程出现JSONException则记录错误日志，最后通过调用父类的setNotes方法将处理后的JSONObject转换为字符串进行存储，并设置名称为特定的元数据名称（GTaskStringUtils.META_NOTE_NAME），用于设置元数据相关信息并关联对应的 GTask 标识。
+getRelatedGid方法
+所属类：MetaData
+功能：返回记录的关联 GTask 的标识（mRelatedGid），用于获取元数据所关联的 GTask 相关标识信息。
+isWorthSaving方法
+所属类：MetaData
+功能：重写了父类的该方法，通过判断通过getNotes方法获取到的元数据内容是否为null，返回表示是否值得保存的布尔值，用于确定当前元数据对象是否有需要保存的数据内容。
+setContentByRemoteJSON方法
+所属类：MetaData
+功能：首先调用父类的setContentByRemoteJSON方法，然后在确保获取到的元数据内容不为null的情况下，尝试将其转换为JSONObject并从中获取关联 GTask 的标识（mRelatedGid），若获取过程出现JSONException则记录警告日志并将mRelatedGid设为null，用于根据远程传来的 JSON 数据设置元数据内容并解析出关联的 GTask 标识。
+setContentByLocalJSON方法
+所属类：MetaData
+功能：明确抛出IllegalAccessError异常，表示该方法不应被调用，用于限制该方法在当前类中的使用情况，体现特定业务逻辑下对本地 JSON 设置元数据内容操作的禁止。
+getLocalJSONFromContent方法
+所属类：MetaData
+功能：抛出IllegalAccessError异常，表明该方法不应被调用，用于阻止在当前类中执行从内容获取本地 JSON 的操作，同样是基于特定业务逻辑对该功能的限制。
+getSyncAction方法
+所属类：MetaData
+功能：抛出IllegalAccessError异常，意味着该方法不应被调用，用于限定在该类中不能进行获取同步操作相关的调用，体现对元数据在同步操作方面的特定处理规则。
+ */
+
+package net.micode.notes.gtask.data;
+
+import android.database.Cursor;
+import android.util.Log;
+
+import net.micode.notes.tool.GTaskStringUtils;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+
+public class MetaData extends Task {
+    private final static String TAG = MetaData.class.getSimpleName();
+
+    private String mRelatedGid = null;
+
+    public void setMeta(String gid, JSONObject metaInfo) {
+        try {
+            metaInfo.put(GTaskStringUtils.META_HEAD_GTASK_ID, gid);
+        } catch (JSONException e) {
+            Log.e(TAG, "failed to put related gid");
+        }
+        setNotes(metaInfo.toString());
+        setName(GTaskStringUtils.META_NOTE_NAME);
+    }
+
+    public String getRelatedGid() {
+        return mRelatedGid;
+    }
+
+    @Override
+    public boolean isWorthSaving() {
+        return getNotes() != null;
+    }
+
+    @Override
+    public void setContentByRemoteJSON(JSONObject js) {
+        super.setContentByRemoteJSON(js);
+        if (getNotes() != null) {
+            try {
+                JSONObject metaInfo = new JSONObject(getNotes().trim());
+                mRelatedGid = metaInfo.getString(GTaskStringUtils.META_HEAD_GTASK_ID);
+            } catch (JSONException e) {
+                Log.w(TAG, "failed to get related gid");
+                mRelatedGid = null;
+            }
+        }
+    }
+
+    @Override
+    public void setContentByLocalJSON(JSONObject js) {
+        // this function should not be called
+        throw new IllegalAccessError("MetaData:setContentByLocalJSON should not be called");
+    }
+
+    @Override
+    public JSONObject getLocalJSONFromContent() {
+        throw new IllegalAccessError("MetaData:getLocalJSONFromContent should not be called");
+    }
+
+    @Override
+    public int getSyncAction(Cursor c) {
+        throw new IllegalAccessError("MetaData:getSyncAction should not be called");
+    }
+
+}

java/net/micode/notes/gtask/data/Node.java

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 这段 Java 代码定义了抽象类Node，它为后续相关具体数据类构建了一个基础框架，规定了一系列与数据同步操作以及数据内容设置、获取相关的抽象方法，同时定义了表示不同同步动作类型的常量。这些常量涵盖了从无操作、远程或本地添加、删除、更新，到更新冲突以及出现错误等多种同步情况，类中的属性则记录了如唯一标识（mGid）、名称（mName）、最后修改时间（mLastModified）和删除状态（mDeleted）等基础数据信息，整体为处理具有同步需求的数据对象提供了统一的结构和行为规范。
+ */
+
+package net.micode.notes.gtask.data;
+
+import android.database.Cursor;
+
+import org.json.JSONObject;
+
+public abstract class Node {
+    public static final int SYNC_ACTION_NONE = 0;
+
+    public static final int SYNC_ACTION_ADD_REMOTE = 1;
+
+    public static final int SYNC_ACTION_ADD_LOCAL = 2;
+
+    public static final int SYNC_ACTION_DEL_REMOTE = 3;
+
+    public static final int SYNC_ACTION_DEL_LOCAL = 4;
+
+    public static final int SYNC_ACTION_UPDATE_REMOTE = 5;
+
+    public static final int SYNC_ACTION_UPDATE_LOCAL = 6;
+
+    public static final int SYNC_ACTION_UPDATE_CONFLICT = 7;
+
+    public static final int SYNC_ACTION_ERROR = 8;
+
+    private String mGid;
+
+    private String mName;
+
+    private long mLastModified;
+
+    private boolean mDeleted;
+
+    public Node() {
+        mGid = null;
+        mName = "";
+        mLastModified = 0;
+        mDeleted = false;
+    }
+
+    public abstract JSONObject getCreateAction(int actionId);
+
+    public abstract JSONObject getUpdateAction(int actionId);
+
+    public abstract void setContentByRemoteJSON(JSONObject js);
+
+    public abstract void setContentByLocalJSON(JSONObject js);
+
+    public abstract JSONObject getLocalJSONFromContent();
+
+    public abstract int getSyncAction(Cursor c);
+
+    public void setGid(String gid) {
+        this.mGid = gid;
+    }
+
+    public void setName(String name) {
+        this.mName = name;
+    }
+
+    public void setLastModified(long lastModified) {
+        this.mLastModified = lastModified;
+    }
+
+    public void setDeleted(boolean deleted) {
+        this.mDeleted = deleted;
+    }
+
+    public String getGid() {
+        return this.mGid;
+    }
+
+    public String getName() {
+        return this.mName;
+    }
+
+    public long getLastModified() {
+        return this.mLastModified;
+    }
+
+    public boolean getDeleted() {
+        return this.mDeleted;
+    }
+
+}

java/net/micode/notes/gtask/data/SqlData.java

@@ -0,0 +1,242 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 这段 Java 代码定义了Task类，它继承自抽象类Node，是用于处理任务相关数据及操作的核心类，围绕任务在与 GTask 数据交互（如创建、更新动作对应的 JSON 构建，以及从 JSON 解析数据等）、同步操作判断、数据完整性判断（是否值得保存）以及各类属性设置与获取等方面构建功能逻辑。类中通过对抽象方法的实现，规范了任务数据在不同场景下的序列化与反序列化操作，同时结合自身属性（如完成状态、备注信息、关联的前置任务和父任务列表等），全方位地对任务对象进行管理与操作，在涉及任务数据的同步、展示与持久化存储等业务场景中起着关键作用。
+函数分析
+Task类构造函数
+所属类：Task
+功能：调用父类构造函数进行初始化后，对自身特有的属性进行初始化，将完成状态设为false，备注信息设为null，前置任务设为null，父任务列表设为null，元数据信息设为null，为后续根据业务需求设置这些属性值准备初始状态。
+getCreateAction方法
+所属类：Task
+功能：创建一个新的JSONObject对象，按照 GTask 相关的数据格式要求，向其中添加如动作类型（创建）、动作ID、任务在父任务列表中的索引、任务实体相关数据（名称、创建者ID、类型、备注等）、父任务ID、目标父任务类型、列表ID以及前置任务ID（若存在）等信息，若添加过程出现JSONException则记录错误日志、打印堆栈信息并抛出异常，最终返回构建好的用于创建任务的JSONObject，用于生成创建任务操作对应的 JSON 数据结构。
+getUpdateAction方法
+所属类：Task
+功能：同样先创建一个JSONObject对象，然后依据 GTask 格式规范，向其中添加动作类型（更新）、动作ID、任务ID以及任务实体更新相关的数据（名称、备注、删除状态等），若出现JSONException则记录错误日志、打印堆栈信息并抛出异常，最后返回该JSONObject，用于构建任务更新操作对应的 JSON 数据内容。
+setContentByRemoteJSON方法
+所属类：Task
+功能：在传入的JSONObject不为null的前提下，尝试从其中获取并设置任务的相关属性信息，包括ID、最后修改时间、名称、备注、删除状态以及完成状态等，若获取过程出现JSONException则记录错误日志、打印堆栈信息并抛出异常，用于根据远程传来的 JSON 数据更新任务对象的属性内容。
+setContentByLocalJSON方法
+所属类：Task
+功能：先对传入的JSONObject进行有效性判断，若不符合要求则记录警告日志，若符合则尝试从中解析出笔记相关信息，进一步判断笔记类型是否合法，然后遍历数据数组，找到类型为普通笔记的数据项，将其内容设置为任务的名称，用于依据本地 JSON 数据设置任务的名称等相关属性。
+getLocalJSONFromContent方法
+所属类：Task
+功能：根据元数据信息（mMetaInfo）是否为null分情况处理，若为null且任务名称也为null则记录警告日志并返回null，否则构建一个新的JSONObject，按照特定格式填充任务相关数据（如笔记内容、类型等）并返回；若mMetaInfo不为null，则从其中获取并更新对应的数据（如将任务名称更新到相关数据项中），最后返回处理后的JSONObject，用于生成基于任务当前内容的本地 JSON 数据表示形式。
+setMetaInfo方法
+所属类：Task
+功能：在传入的MetaData对象不为null且其备注信息不为null的情况下，尝试将备注信息转换为JSONObject并赋值给mMetaInfo属性，若转换出现JSONException则记录警告日志并将mMetaInfo设为null，用于设置任务的元数据信息，方便后续基于元数据进行相关操作与判断。
+getSyncAction方法
+所属类：Task
+功能：通过一系列复杂的条件判断来确定任务的同步操作类型，首先尝试获取元数据中的笔记相关信息，基于其是否存在以及笔记ID等信息与游标数据的对比，结合本地是否有更新、同步ID与最后修改时间是否匹配、GTask ID是否一致等多方面因素，按照不同情况返回对应的同步操作类型常量（如无操作、本地更新、远程更新、更新冲突、出现错误等），若过程中出现异常则记录错误日志并打印堆栈信息，用于判断任务在数据同步过程中的操作类型。
+isWorthSaving方法
+所属类：Task
+功能：通过判断元数据信息是否为null，以及任务名称和备注信息去除空白字符后长度是否大于0等条件，返回表示任务是否值得保存的布尔值，用于确定任务对象当前的数据状态是否有保存的必要。
+setCompleted方法
+所属类：Task
+功能：接收一个布尔型参数completed，将其赋值给mCompleted属性，用于设置任务的完成状态，满足业务场景中对任务完成与否的标记需求。
+setNotes方法
+所属类：Task
+功能：传入一个字符串参数notes，将其赋值给mNotes属性，用于更新任务的备注信息，方便在不同阶段修改任务的相关说明内容。
+setPriorSibling方法
+所属类：Task
+功能：接受一个Task类型的参数priorSibling，将其赋值给mPriorSibling属性，用于设置任务的前置任务，构建任务之间的先后顺序关联关系。
+setParent方法
+所属类：Task
+功能：接收一个TaskList类型的参数parent，将其赋值给mParent属性，用于设置任务所属的父任务列表，确立任务在任务层级结构中的归属关系。
+getCompleted方法
+所属类：Task
+功能：返回mCompleted属性的值，也就是任务的完成状态，用于获取任务是否已完成的相关信息，便于展示、筛选等业务操作。
+getNotes方法
+所属类：Task
+功能：返回mNotes属性的值，即任务的备注信息，用于获取任务的相关说明内容，在查看、编辑任务详情等场景下会用到。
+getPriorSibling方法
+所属类：Task
+功能：返回mPriorSibling属性的值，也就是任务的前置任务对象，方便在处理任务顺序、依赖关系等业务逻辑中获取前置任务相关信息。
+getParent方法
+所属类：Task
+功能：返回mParent属性的值，即任务所属的父任务列表对象，用于获取任务在任务层级结构中的上层归属信息，有助于进行任务分组、层级展示等操作。
+ */
+
+package net.micode.notes.gtask.data;
+
+import android.content.ContentResolver;
+import android.content.ContentUris;
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.Cursor;
+import android.net.Uri;
+import android.util.Log;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.DataConstants;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.data.NotesDatabaseHelper.TABLE;
+import net.micode.notes.gtask.exception.ActionFailureException;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+
+public class SqlData {
+    private static final String TAG = SqlData.class.getSimpleName();
+
+    private static final int INVALID_ID = -99999;
+
+    public static final String[] PROJECTION_DATA = new String[] {
+            DataColumns.ID, DataColumns.MIME_TYPE, DataColumns.CONTENT, DataColumns.DATA1,
+            DataColumns.DATA3
+    };
+
+    public static final int DATA_ID_COLUMN = 0;
+
+    public static final int DATA_MIME_TYPE_COLUMN = 1;
+
+    public static final int DATA_CONTENT_COLUMN = 2;
+
+    public static final int DATA_CONTENT_DATA_1_COLUMN = 3;
+
+    public static final int DATA_CONTENT_DATA_3_COLUMN = 4;
+
+    private ContentResolver mContentResolver;
+
+    private boolean mIsCreate;
+
+    private long mDataId;
+
+    private String mDataMimeType;
+
+    private String mDataContent;
+
+    private long mDataContentData1;
+
+    private String mDataContentData3;
+
+    private ContentValues mDiffDataValues;
+
+    public SqlData(Context context) {
+        mContentResolver = context.getContentResolver();
+        mIsCreate = true;
+        mDataId = INVALID_ID;
+        mDataMimeType = DataConstants.NOTE;
+        mDataContent = "";
+        mDataContentData1 = 0;
+        mDataContentData3 = "";
+        mDiffDataValues = new ContentValues();
+    }
+
+    public SqlData(Context context, Cursor c) {
+        mContentResolver = context.getContentResolver();
+        mIsCreate = false;
+        loadFromCursor(c);
+        mDiffDataValues = new ContentValues();
+    }
+
+    private void loadFromCursor(Cursor c) {
+        mDataId = c.getLong(DATA_ID_COLUMN);
+        mDataMimeType = c.getString(DATA_MIME_TYPE_COLUMN);
+        mDataContent = c.getString(DATA_CONTENT_COLUMN);
+        mDataContentData1 = c.getLong(DATA_CONTENT_DATA_1_COLUMN);
+        mDataContentData3 = c.getString(DATA_CONTENT_DATA_3_COLUMN);
+    }
+
+    public void setContent(JSONObject js) throws JSONException {
+        long dataId = js.has(DataColumns.ID) ? js.getLong(DataColumns.ID) : INVALID_ID;
+        if (mIsCreate || mDataId != dataId) {
+            mDiffDataValues.put(DataColumns.ID, dataId);
+        }
+        mDataId = dataId;
+
+        String dataMimeType = js.has(DataColumns.MIME_TYPE) ? js.getString(DataColumns.MIME_TYPE)
+                : DataConstants.NOTE;
+        if (mIsCreate || !mDataMimeType.equals(dataMimeType)) {
+            mDiffDataValues.put(DataColumns.MIME_TYPE, dataMimeType);
+        }
+        mDataMimeType = dataMimeType;
+
+        String dataContent = js.has(DataColumns.CONTENT) ? js.getString(DataColumns.CONTENT) : "";
+        if (mIsCreate || !mDataContent.equals(dataContent)) {
+            mDiffDataValues.put(DataColumns.CONTENT, dataContent);
+        }
+        mDataContent = dataContent;
+
+        long dataContentData1 = js.has(DataColumns.DATA1) ? js.getLong(DataColumns.DATA1) : 0;
+        if (mIsCreate || mDataContentData1 != dataContentData1) {
+            mDiffDataValues.put(DataColumns.DATA1, dataContentData1);
+        }
+        mDataContentData1 = dataContentData1;
+
+        String dataContentData3 = js.has(DataColumns.DATA3) ? js.getString(DataColumns.DATA3) : "";
+        if (mIsCreate || !mDataContentData3.equals(dataContentData3)) {
+            mDiffDataValues.put(DataColumns.DATA3, dataContentData3);
+        }
+        mDataContentData3 = dataContentData3;
+    }
+
+    public JSONObject getContent() throws JSONException {
+        if (mIsCreate) {
+            Log.e(TAG, "it seems that we haven't created this in database yet");
+            return null;
+        }
+        JSONObject js = new JSONObject();
+        js.put(DataColumns.ID, mDataId);
+        js.put(DataColumns.MIME_TYPE, mDataMimeType);
+        js.put(DataColumns.CONTENT, mDataContent);
+        js.put(DataColumns.DATA1, mDataContentData1);
+        js.put(DataColumns.DATA3, mDataContentData3);
+        return js;
+    }
+
+    public void commit(long noteId, boolean validateVersion, long version) {
+
+        if (mIsCreate) {
+            if (mDataId == INVALID_ID && mDiffDataValues.containsKey(DataColumns.ID)) {
+                mDiffDataValues.remove(DataColumns.ID);
+            }
+
+            mDiffDataValues.put(DataColumns.NOTE_ID, noteId);
+            Uri uri = mContentResolver.insert(Notes.CONTENT_DATA_URI, mDiffDataValues);
+            try {
+                mDataId = Long.valueOf(uri.getPathSegments().get(1));
+            } catch (NumberFormatException e) {
+                Log.e(TAG, "Get note id error :" + e.toString());
+                throw new ActionFailureException("create note failed");
+            }
+        } else {
+            if (mDiffDataValues.size() > 0) {
+                int result = 0;
+                if (!validateVersion) {
+                    result = mContentResolver.update(ContentUris.withAppendedId(
+                            Notes.CONTENT_DATA_URI, mDataId), mDiffDataValues, null, null);
+                } else {
+                    result = mContentResolver.update(ContentUris.withAppendedId(
+                            Notes.CONTENT_DATA_URI, mDataId), mDiffDataValues,
+                            " ? in (SELECT " + NoteColumns.ID + " FROM " + TABLE.NOTE
+                                    + " WHERE " + NoteColumns.VERSION + "=?)", new String[] {
+                                    String.valueOf(noteId), String.valueOf(version)
+                            });
+                }
+                if (result == 0) {
+                    Log.w(TAG, "there is no update. maybe user updates note when syncing");
+                }
+            }
+        }
+
+        mDiffDataValues.clear();
+        mIsCreate = false;
+    }
+
+    public long getId() {
+        return mDataId;
+    }
+}

java/net/micode/notes/gtask/data/SqlNote.java

@@ -0,0 +1,505 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.data;
+
+import android.appwidget.AppWidgetManager;
+import android.content.ContentResolver;
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.Cursor;
+import android.net.Uri;
+import android.util.Log;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.gtask.exception.ActionFailureException;
+import net.micode.notes.tool.GTaskStringUtils;
+import net.micode.notes.tool.ResourceParser;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.util.ArrayList;
+
+
+public class SqlNote {
+    private static final String TAG = SqlNote.class.getSimpleName();
+
+    private static final int INVALID_ID = -99999;
+
+    public static final String[] PROJECTION_NOTE = new String[] {
+            NoteColumns.ID, NoteColumns.ALERTED_DATE, NoteColumns.BG_COLOR_ID,
+            NoteColumns.CREATED_DATE, NoteColumns.HAS_ATTACHMENT, NoteColumns.MODIFIED_DATE,
+            NoteColumns.NOTES_COUNT, NoteColumns.PARENT_ID, NoteColumns.SNIPPET, NoteColumns.TYPE,
+            NoteColumns.WIDGET_ID, NoteColumns.WIDGET_TYPE, NoteColumns.SYNC_ID,
+            NoteColumns.LOCAL_MODIFIED, NoteColumns.ORIGIN_PARENT_ID, NoteColumns.GTASK_ID,
+            NoteColumns.VERSION
+    };
+
+    public static final int ID_COLUMN = 0;
+
+    public static final int ALERTED_DATE_COLUMN = 1;
+
+    public static final int BG_COLOR_ID_COLUMN = 2;
+
+    public static final int CREATED_DATE_COLUMN = 3;
+
+    public static final int HAS_ATTACHMENT_COLUMN = 4;
+
+    public static final int MODIFIED_DATE_COLUMN = 5;
+
+    public static final int NOTES_COUNT_COLUMN = 6;
+
+    public static final int PARENT_ID_COLUMN = 7;
+
+    public static final int SNIPPET_COLUMN = 8;
+
+    public static final int TYPE_COLUMN = 9;
+
+    public static final int WIDGET_ID_COLUMN = 10;
+
+    public static final int WIDGET_TYPE_COLUMN = 11;
+
+    public static final int SYNC_ID_COLUMN = 12;
+
+    public static final int LOCAL_MODIFIED_COLUMN = 13;
+
+    public static final int ORIGIN_PARENT_ID_COLUMN = 14;
+
+    public static final int GTASK_ID_COLUMN = 15;
+
+    public static final int VERSION_COLUMN = 16;
+
+    private Context mContext;
+
+    private ContentResolver mContentResolver;
+
+    private boolean mIsCreate;
+
+    private long mId;
+
+    private long mAlertDate;
+
+    private int mBgColorId;
+
+    private long mCreatedDate;
+
+    private int mHasAttachment;
+
+    private long mModifiedDate;
+
+    private long mParentId;
+
+    private String mSnippet;
+
+    private int mType;
+
+    private int mWidgetId;
+
+    private int mWidgetType;
+
+    private long mOriginParent;
+
+    private long mVersion;
+
+    private ContentValues mDiffNoteValues;
+
+    private ArrayList<SqlData> mDataList;
+
+    public SqlNote(Context context) {
+        mContext = context;
+        mContentResolver = context.getContentResolver();
+        mIsCreate = true;
+        mId = INVALID_ID;
+        mAlertDate = 0;
+        mBgColorId = ResourceParser.getDefaultBgId(context);
+        mCreatedDate = System.currentTimeMillis();
+        mHasAttachment = 0;
+        mModifiedDate = System.currentTimeMillis();
+        mParentId = 0;
+        mSnippet = "";
+        mType = Notes.TYPE_NOTE;
+        mWidgetId = AppWidgetManager.INVALID_APPWIDGET_ID;
+        mWidgetType = Notes.TYPE_WIDGET_INVALIDE;
+        mOriginParent = 0;
+        mVersion = 0;
+        mDiffNoteValues = new ContentValues();
+        mDataList = new ArrayList<SqlData>();
+    }
+
+    public SqlNote(Context context, Cursor c) {
+        mContext = context;
+        mContentResolver = context.getContentResolver();
+        mIsCreate = false;
+        loadFromCursor(c);
+        mDataList = new ArrayList<SqlData>();
+        if (mType == Notes.TYPE_NOTE)
+            loadDataContent();
+        mDiffNoteValues = new ContentValues();
+    }
+
+    public SqlNote(Context context, long id) {
+        mContext = context;
+        mContentResolver = context.getContentResolver();
+        mIsCreate = false;
+        loadFromCursor(id);
+        mDataList = new ArrayList<SqlData>();
+        if (mType == Notes.TYPE_NOTE)
+            loadDataContent();
+        mDiffNoteValues = new ContentValues();
+
+    }
+
+    private void loadFromCursor(long id) {
+        Cursor c = null;
+        try {
+            c = mContentResolver.query(Notes.CONTENT_NOTE_URI, PROJECTION_NOTE, "(_id=?)",
+                    new String[] {
+                        String.valueOf(id)
+                    }, null);
+            if (c != null) {
+                c.moveToNext();
+                loadFromCursor(c);
+            } else {
+                Log.w(TAG, "loadFromCursor: cursor = null");
+            }
+        } finally {
+            if (c != null)
+                c.close();
+        }
+    }
+
+    private void loadFromCursor(Cursor c) {
+        mId = c.getLong(ID_COLUMN);
+        mAlertDate = c.getLong(ALERTED_DATE_COLUMN);
+        mBgColorId = c.getInt(BG_COLOR_ID_COLUMN);
+        mCreatedDate = c.getLong(CREATED_DATE_COLUMN);
+        mHasAttachment = c.getInt(HAS_ATTACHMENT_COLUMN);
+        mModifiedDate = c.getLong(MODIFIED_DATE_COLUMN);
+        mParentId = c.getLong(PARENT_ID_COLUMN);
+        mSnippet = c.getString(SNIPPET_COLUMN);
+        mType = c.getInt(TYPE_COLUMN);
+        mWidgetId = c.getInt(WIDGET_ID_COLUMN);
+        mWidgetType = c.getInt(WIDGET_TYPE_COLUMN);
+        mVersion = c.getLong(VERSION_COLUMN);
+    }
+
+    private void loadDataContent() {
+        Cursor c = null;
+        mDataList.clear();
+        try {
+            c = mContentResolver.query(Notes.CONTENT_DATA_URI, SqlData.PROJECTION_DATA,
+                    "(note_id=?)", new String[] {
+                        String.valueOf(mId)
+                    }, null);
+            if (c != null) {
+                if (c.getCount() == 0) {
+                    Log.w(TAG, "it seems that the note has not data");
+                    return;
+                }
+                while (c.moveToNext()) {
+                    SqlData data = new SqlData(mContext, c);
+                    mDataList.add(data);
+                }
+            } else {
+                Log.w(TAG, "loadDataContent: cursor = null");
+            }
+        } finally {
+            if (c != null)
+                c.close();
+        }
+    }
+
+    public boolean setContent(JSONObject js) {
+        try {
+            JSONObject note = js.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+            if (note.getInt(NoteColumns.TYPE) == Notes.TYPE_SYSTEM) {
+                Log.w(TAG, "cannot set system folder");
+            } else if (note.getInt(NoteColumns.TYPE) == Notes.TYPE_FOLDER) {
+                // for folder we can only update the snnipet and type
+                String snippet = note.has(NoteColumns.SNIPPET) ? note
+                        .getString(NoteColumns.SNIPPET) : "";
+                if (mIsCreate || !mSnippet.equals(snippet)) {
+                    mDiffNoteValues.put(NoteColumns.SNIPPET, snippet);
+                }
+                mSnippet = snippet;
+
+                int type = note.has(NoteColumns.TYPE) ? note.getInt(NoteColumns.TYPE)
+                        : Notes.TYPE_NOTE;
+                if (mIsCreate || mType != type) {
+                    mDiffNoteValues.put(NoteColumns.TYPE, type);
+                }
+                mType = type;
+            } else if (note.getInt(NoteColumns.TYPE) == Notes.TYPE_NOTE) {
+                JSONArray dataArray = js.getJSONArray(GTaskStringUtils.META_HEAD_DATA);
+                long id = note.has(NoteColumns.ID) ? note.getLong(NoteColumns.ID) : INVALID_ID;
+                if (mIsCreate || mId != id) {
+                    mDiffNoteValues.put(NoteColumns.ID, id);
+                }
+                mId = id;
+
+                long alertDate = note.has(NoteColumns.ALERTED_DATE) ? note
+                        .getLong(NoteColumns.ALERTED_DATE) : 0;
+                if (mIsCreate || mAlertDate != alertDate) {
+                    mDiffNoteValues.put(NoteColumns.ALERTED_DATE, alertDate);
+                }
+                mAlertDate = alertDate;
+
+                int bgColorId = note.has(NoteColumns.BG_COLOR_ID) ? note
+                        .getInt(NoteColumns.BG_COLOR_ID) : ResourceParser.getDefaultBgId(mContext);
+                if (mIsCreate || mBgColorId != bgColorId) {
+                    mDiffNoteValues.put(NoteColumns.BG_COLOR_ID, bgColorId);
+                }
+                mBgColorId = bgColorId;
+
+                long createDate = note.has(NoteColumns.CREATED_DATE) ? note
+                        .getLong(NoteColumns.CREATED_DATE) : System.currentTimeMillis();
+                if (mIsCreate || mCreatedDate != createDate) {
+                    mDiffNoteValues.put(NoteColumns.CREATED_DATE, createDate);
+                }
+                mCreatedDate = createDate;
+
+                int hasAttachment = note.has(NoteColumns.HAS_ATTACHMENT) ? note
+                        .getInt(NoteColumns.HAS_ATTACHMENT) : 0;
+                if (mIsCreate || mHasAttachment != hasAttachment) {
+                    mDiffNoteValues.put(NoteColumns.HAS_ATTACHMENT, hasAttachment);
+                }
+                mHasAttachment = hasAttachment;
+
+                long modifiedDate = note.has(NoteColumns.MODIFIED_DATE) ? note
+                        .getLong(NoteColumns.MODIFIED_DATE) : System.currentTimeMillis();
+                if (mIsCreate || mModifiedDate != modifiedDate) {
+                    mDiffNoteValues.put(NoteColumns.MODIFIED_DATE, modifiedDate);
+                }
+                mModifiedDate = modifiedDate;
+
+                long parentId = note.has(NoteColumns.PARENT_ID) ? note
+                        .getLong(NoteColumns.PARENT_ID) : 0;
+                if (mIsCreate || mParentId != parentId) {
+                    mDiffNoteValues.put(NoteColumns.PARENT_ID, parentId);
+                }
+                mParentId = parentId;
+
+                String snippet = note.has(NoteColumns.SNIPPET) ? note
+                        .getString(NoteColumns.SNIPPET) : "";
+                if (mIsCreate || !mSnippet.equals(snippet)) {
+                    mDiffNoteValues.put(NoteColumns.SNIPPET, snippet);
+                }
+                mSnippet = snippet;
+
+                int type = note.has(NoteColumns.TYPE) ? note.getInt(NoteColumns.TYPE)
+                        : Notes.TYPE_NOTE;
+                if (mIsCreate || mType != type) {
+                    mDiffNoteValues.put(NoteColumns.TYPE, type);
+                }
+                mType = type;
+
+                int widgetId = note.has(NoteColumns.WIDGET_ID) ? note.getInt(NoteColumns.WIDGET_ID)
+                        : AppWidgetManager.INVALID_APPWIDGET_ID;
+                if (mIsCreate || mWidgetId != widgetId) {
+                    mDiffNoteValues.put(NoteColumns.WIDGET_ID, widgetId);
+                }
+                mWidgetId = widgetId;
+
+                int widgetType = note.has(NoteColumns.WIDGET_TYPE) ? note
+                        .getInt(NoteColumns.WIDGET_TYPE) : Notes.TYPE_WIDGET_INVALIDE;
+                if (mIsCreate || mWidgetType != widgetType) {
+                    mDiffNoteValues.put(NoteColumns.WIDGET_TYPE, widgetType);
+                }
+                mWidgetType = widgetType;
+
+                long originParent = note.has(NoteColumns.ORIGIN_PARENT_ID) ? note
+                        .getLong(NoteColumns.ORIGIN_PARENT_ID) : 0;
+                if (mIsCreate || mOriginParent != originParent) {
+                    mDiffNoteValues.put(NoteColumns.ORIGIN_PARENT_ID, originParent);
+                }
+                mOriginParent = originParent;
+
+                for (int i = 0; i < dataArray.length(); i++) {
+                    JSONObject data = dataArray.getJSONObject(i);
+                    SqlData sqlData = null;
+                    if (data.has(DataColumns.ID)) {
+                        long dataId = data.getLong(DataColumns.ID);
+                        for (SqlData temp : mDataList) {
+                            if (dataId == temp.getId()) {
+                                sqlData = temp;
+                            }
+                        }
+                    }
+
+                    if (sqlData == null) {
+                        sqlData = new SqlData(mContext);
+                        mDataList.add(sqlData);
+                    }
+
+                    sqlData.setContent(data);
+                }
+            }
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            return false;
+        }
+        return true;
+    }
+
+    public JSONObject getContent() {
+        try {
+            JSONObject js = new JSONObject();
+
+            if (mIsCreate) {
+                Log.e(TAG, "it seems that we haven't created this in database yet");
+                return null;
+            }
+
+            JSONObject note = new JSONObject();
+            if (mType == Notes.TYPE_NOTE) {
+                note.put(NoteColumns.ID, mId);
+                note.put(NoteColumns.ALERTED_DATE, mAlertDate);
+                note.put(NoteColumns.BG_COLOR_ID, mBgColorId);
+                note.put(NoteColumns.CREATED_DATE, mCreatedDate);
+                note.put(NoteColumns.HAS_ATTACHMENT, mHasAttachment);
+                note.put(NoteColumns.MODIFIED_DATE, mModifiedDate);
+                note.put(NoteColumns.PARENT_ID, mParentId);
+                note.put(NoteColumns.SNIPPET, mSnippet);
+                note.put(NoteColumns.TYPE, mType);
+                note.put(NoteColumns.WIDGET_ID, mWidgetId);
+                note.put(NoteColumns.WIDGET_TYPE, mWidgetType);
+                note.put(NoteColumns.ORIGIN_PARENT_ID, mOriginParent);
+                js.put(GTaskStringUtils.META_HEAD_NOTE, note);
+
+                JSONArray dataArray = new JSONArray();
+                for (SqlData sqlData : mDataList) {
+                    JSONObject data = sqlData.getContent();
+                    if (data != null) {
+                        dataArray.put(data);
+                    }
+                }
+                js.put(GTaskStringUtils.META_HEAD_DATA, dataArray);
+            } else if (mType == Notes.TYPE_FOLDER || mType == Notes.TYPE_SYSTEM) {
+                note.put(NoteColumns.ID, mId);
+                note.put(NoteColumns.TYPE, mType);
+                note.put(NoteColumns.SNIPPET, mSnippet);
+                js.put(GTaskStringUtils.META_HEAD_NOTE, note);
+            }
+
+            return js;
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+        }
+        return null;
+    }
+
+    public void setParentId(long id) {
+        mParentId = id;
+        mDiffNoteValues.put(NoteColumns.PARENT_ID, id);
+    }
+
+    public void setGtaskId(String gid) {
+        mDiffNoteValues.put(NoteColumns.GTASK_ID, gid);
+    }
+
+    public void setSyncId(long syncId) {
+        mDiffNoteValues.put(NoteColumns.SYNC_ID, syncId);
+    }
+
+    public void resetLocalModified() {
+        mDiffNoteValues.put(NoteColumns.LOCAL_MODIFIED, 0);
+    }
+
+    public long getId() {
+        return mId;
+    }
+
+    public long getParentId() {
+        return mParentId;
+    }
+
+    public String getSnippet() {
+        return mSnippet;
+    }
+
+    public boolean isNoteType() {
+        return mType == Notes.TYPE_NOTE;
+    }
+
+    public void commit(boolean validateVersion) {
+        if (mIsCreate) {
+            if (mId == INVALID_ID && mDiffNoteValues.containsKey(NoteColumns.ID)) {
+                mDiffNoteValues.remove(NoteColumns.ID);
+            }
+
+            Uri uri = mContentResolver.insert(Notes.CONTENT_NOTE_URI, mDiffNoteValues);
+            try {
+                mId = Long.valueOf(uri.getPathSegments().get(1));
+            } catch (NumberFormatException e) {
+                Log.e(TAG, "Get note id error :" + e.toString());
+                throw new ActionFailureException("create note failed");
+            }
+            if (mId == 0) {
+                throw new IllegalStateException("Create thread id failed");
+            }
+
+            if (mType == Notes.TYPE_NOTE) {
+                for (SqlData sqlData : mDataList) {
+                    sqlData.commit(mId, false, -1);
+                }
+            }
+        } else {
+            if (mId <= 0 && mId != Notes.ID_ROOT_FOLDER && mId != Notes.ID_CALL_RECORD_FOLDER) {
+                Log.e(TAG, "No such note");
+                throw new IllegalStateException("Try to update note with invalid id");
+            }
+            if (mDiffNoteValues.size() > 0) {
+                mVersion ++;
+                int result = 0;
+                if (!validateVersion) {
+                    result = mContentResolver.update(Notes.CONTENT_NOTE_URI, mDiffNoteValues, "("
+                            + NoteColumns.ID + "=?)", new String[] {
+                        String.valueOf(mId)
+                    });
+                } else {
+                    result = mContentResolver.update(Notes.CONTENT_NOTE_URI, mDiffNoteValues, "("
+                            + NoteColumns.ID + "=?) AND (" + NoteColumns.VERSION + "<=?)",
+                            new String[] {
+                                    String.valueOf(mId), String.valueOf(mVersion)
+                            });
+                }
+                if (result == 0) {
+                    Log.w(TAG, "there is no update. maybe user updates note when syncing");
+                }
+            }
+
+            if (mType == Notes.TYPE_NOTE) {
+                for (SqlData sqlData : mDataList) {
+                    sqlData.commit(mId, validateVersion, mVersion);
+                }
+            }
+        }
+
+        // refresh local info
+        loadFromCursor(mId);
+        if (mType == Notes.TYPE_NOTE)
+            loadDataContent();
+
+        mDiffNoteValues.clear();
+        mIsCreate = false;
+    }
+}

java/net/micode/notes/gtask/data/Task.java

@@ -0,0 +1,351 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.data;
+
+import android.database.Cursor;
+import android.text.TextUtils;
+import android.util.Log;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.DataConstants;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.gtask.exception.ActionFailureException;
+import net.micode.notes.tool.GTaskStringUtils;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+
+public class Task extends Node {
+    private static final String TAG = Task.class.getSimpleName();
+
+    private boolean mCompleted;
+
+    private String mNotes;
+
+    private JSONObject mMetaInfo;
+
+    private Task mPriorSibling;
+
+    private TaskList mParent;
+
+    public Task() {
+        super();
+        mCompleted = false;
+        mNotes = null;
+        mPriorSibling = null;
+        mParent = null;
+        mMetaInfo = null;
+    }
+
+    public JSONObject getCreateAction(int actionId) {
+        JSONObject js = new JSONObject();
+
+        try {
+            // action_type
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
+                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_CREATE);
+
+            // action_id
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, actionId);
+
+            // index
+            js.put(GTaskStringUtils.GTASK_JSON_INDEX, mParent.getChildTaskIndex(this));
+
+            // entity_delta
+            JSONObject entity = new JSONObject();
+            entity.put(GTaskStringUtils.GTASK_JSON_NAME, getName());
+            entity.put(GTaskStringUtils.GTASK_JSON_CREATOR_ID, "null");
+            entity.put(GTaskStringUtils.GTASK_JSON_ENTITY_TYPE,
+                    GTaskStringUtils.GTASK_JSON_TYPE_TASK);
+            if (getNotes() != null) {
+                entity.put(GTaskStringUtils.GTASK_JSON_NOTES, getNotes());
+            }
+            js.put(GTaskStringUtils.GTASK_JSON_ENTITY_DELTA, entity);
+
+            // parent_id
+            js.put(GTaskStringUtils.GTASK_JSON_PARENT_ID, mParent.getGid());
+
+            // dest_parent_type
+            js.put(GTaskStringUtils.GTASK_JSON_DEST_PARENT_TYPE,
+                    GTaskStringUtils.GTASK_JSON_TYPE_GROUP);
+
+            // list_id
+            js.put(GTaskStringUtils.GTASK_JSON_LIST_ID, mParent.getGid());
+
+            // prior_sibling_id
+            if (mPriorSibling != null) {
+                js.put(GTaskStringUtils.GTASK_JSON_PRIOR_SIBLING_ID, mPriorSibling.getGid());
+            }
+
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("fail to generate task-create jsonobject");
+        }
+
+        return js;
+    }
+
+    public JSONObject getUpdateAction(int actionId) {
+        JSONObject js = new JSONObject();
+
+        try {
+            // action_type
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
+                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_UPDATE);
+
+            // action_id
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, actionId);
+
+            // id
+            js.put(GTaskStringUtils.GTASK_JSON_ID, getGid());
+
+            // entity_delta
+            JSONObject entity = new JSONObject();
+            entity.put(GTaskStringUtils.GTASK_JSON_NAME, getName());
+            if (getNotes() != null) {
+                entity.put(GTaskStringUtils.GTASK_JSON_NOTES, getNotes());
+            }
+            entity.put(GTaskStringUtils.GTASK_JSON_DELETED, getDeleted());
+            js.put(GTaskStringUtils.GTASK_JSON_ENTITY_DELTA, entity);
+
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("fail to generate task-update jsonobject");
+        }
+
+        return js;
+    }
+
+    public void setContentByRemoteJSON(JSONObject js) {
+        if (js != null) {
+            try {
+                // id
+                if (js.has(GTaskStringUtils.GTASK_JSON_ID)) {
+                    setGid(js.getString(GTaskStringUtils.GTASK_JSON_ID));
+                }
+
+                // last_modified
+                if (js.has(GTaskStringUtils.GTASK_JSON_LAST_MODIFIED)) {
+                    setLastModified(js.getLong(GTaskStringUtils.GTASK_JSON_LAST_MODIFIED));
+                }
+
+                // name
+                if (js.has(GTaskStringUtils.GTASK_JSON_NAME)) {
+                    setName(js.getString(GTaskStringUtils.GTASK_JSON_NAME));
+                }
+
+                // notes
+                if (js.has(GTaskStringUtils.GTASK_JSON_NOTES)) {
+                    setNotes(js.getString(GTaskStringUtils.GTASK_JSON_NOTES));
+                }
+
+                // deleted
+                if (js.has(GTaskStringUtils.GTASK_JSON_DELETED)) {
+                    setDeleted(js.getBoolean(GTaskStringUtils.GTASK_JSON_DELETED));
+                }
+
+                // completed
+                if (js.has(GTaskStringUtils.GTASK_JSON_COMPLETED)) {
+                    setCompleted(js.getBoolean(GTaskStringUtils.GTASK_JSON_COMPLETED));
+                }
+            } catch (JSONException e) {
+                Log.e(TAG, e.toString());
+                e.printStackTrace();
+                throw new ActionFailureException("fail to get task content from jsonobject");
+            }
+        }
+    }
+
+    public void setContentByLocalJSON(JSONObject js) {
+        if (js == null || !js.has(GTaskStringUtils.META_HEAD_NOTE)
+                || !js.has(GTaskStringUtils.META_HEAD_DATA)) {
+            Log.w(TAG, "setContentByLocalJSON: nothing is avaiable");
+        }
+
+        try {
+            JSONObject note = js.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+            JSONArray dataArray = js.getJSONArray(GTaskStringUtils.META_HEAD_DATA);
+
+            if (note.getInt(NoteColumns.TYPE) != Notes.TYPE_NOTE) {
+                Log.e(TAG, "invalid type");
+                return;
+            }
+
+            for (int i = 0; i < dataArray.length(); i++) {
+                JSONObject data = dataArray.getJSONObject(i);
+                if (TextUtils.equals(data.getString(DataColumns.MIME_TYPE), DataConstants.NOTE)) {
+                    setName(data.getString(DataColumns.CONTENT));
+                    break;
+                }
+            }
+
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+        }
+    }
+
+    public JSONObject getLocalJSONFromContent() {
+        String name = getName();
+        try {
+            if (mMetaInfo == null) {
+                // new task created from web
+                if (name == null) {
+                    Log.w(TAG, "the note seems to be an empty one");
+                    return null;
+                }
+
+                JSONObject js = new JSONObject();
+                JSONObject note = new JSONObject();
+                JSONArray dataArray = new JSONArray();
+                JSONObject data = new JSONObject();
+                data.put(DataColumns.CONTENT, name);
+                dataArray.put(data);
+                js.put(GTaskStringUtils.META_HEAD_DATA, dataArray);
+                note.put(NoteColumns.TYPE, Notes.TYPE_NOTE);
+                js.put(GTaskStringUtils.META_HEAD_NOTE, note);
+                return js;
+            } else {
+                // synced task
+                JSONObject note = mMetaInfo.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+                JSONArray dataArray = mMetaInfo.getJSONArray(GTaskStringUtils.META_HEAD_DATA);
+
+                for (int i = 0; i < dataArray.length(); i++) {
+                    JSONObject data = dataArray.getJSONObject(i);
+                    if (TextUtils.equals(data.getString(DataColumns.MIME_TYPE), DataConstants.NOTE)) {
+                        data.put(DataColumns.CONTENT, getName());
+                        break;
+                    }
+                }
+
+                note.put(NoteColumns.TYPE, Notes.TYPE_NOTE);
+                return mMetaInfo;
+            }
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+    public void setMetaInfo(MetaData metaData) {
+        if (metaData != null && metaData.getNotes() != null) {
+            try {
+                mMetaInfo = new JSONObject(metaData.getNotes());
+            } catch (JSONException e) {
+                Log.w(TAG, e.toString());
+                mMetaInfo = null;
+            }
+        }
+    }
+
+    public int getSyncAction(Cursor c) {
+        try {
+            JSONObject noteInfo = null;
+            if (mMetaInfo != null && mMetaInfo.has(GTaskStringUtils.META_HEAD_NOTE)) {
+                noteInfo = mMetaInfo.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+            }
+
+            if (noteInfo == null) {
+                Log.w(TAG, "it seems that note meta has been deleted");
+                return SYNC_ACTION_UPDATE_REMOTE;
+            }
+
+            if (!noteInfo.has(NoteColumns.ID)) {
+                Log.w(TAG, "remote note id seems to be deleted");
+                return SYNC_ACTION_UPDATE_LOCAL;
+            }
+
+            // validate the note id now
+            if (c.getLong(SqlNote.ID_COLUMN) != noteInfo.getLong(NoteColumns.ID)) {
+                Log.w(TAG, "note id doesn't match");
+                return SYNC_ACTION_UPDATE_LOCAL;
+            }
+
+            if (c.getInt(SqlNote.LOCAL_MODIFIED_COLUMN) == 0) {
+                // there is no local update
+                if (c.getLong(SqlNote.SYNC_ID_COLUMN) == getLastModified()) {
+                    // no update both side
+                    return SYNC_ACTION_NONE;
+                } else {
+                    // apply remote to local
+                    return SYNC_ACTION_UPDATE_LOCAL;
+                }
+            } else {
+                // validate gtask id
+                if (!c.getString(SqlNote.GTASK_ID_COLUMN).equals(getGid())) {
+                    Log.e(TAG, "gtask id doesn't match");
+                    return SYNC_ACTION_ERROR;
+                }
+                if (c.getLong(SqlNote.SYNC_ID_COLUMN) == getLastModified()) {
+                    // local modification only
+                    return SYNC_ACTION_UPDATE_REMOTE;
+                } else {
+                    return SYNC_ACTION_UPDATE_CONFLICT;
+                }
+            }
+        } catch (Exception e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+        }
+
+        return SYNC_ACTION_ERROR;
+    }
+
+    public boolean isWorthSaving() {
+        return mMetaInfo != null || (getName() != null && getName().trim().length() > 0)
+                || (getNotes() != null && getNotes().trim().length() > 0);
+    }
+
+    public void setCompleted(boolean completed) {
+        this.mCompleted = completed;
+    }
+
+    public void setNotes(String notes) {
+        this.mNotes = notes;
+    }
+
+    public void setPriorSibling(Task priorSibling) {
+        this.mPriorSibling = priorSibling;
+    }
+
+    public void setParent(TaskList parent) {
+        this.mParent = parent;
+    }
+
+    public boolean getCompleted() {
+        return this.mCompleted;
+    }
+
+    public String getNotes() {
+        return this.mNotes;
+    }
+
+    public Task getPriorSibling() {
+        return this.mPriorSibling;
+    }
+
+    public TaskList getParent() {
+        return this.mParent;
+    }
+
+}

java/net/micode/notes/gtask/data/TaskList.java

@@ -0,0 +1,403 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了TaskList类，它继承自Node类，主要用于处理任务列表相关的数据与操作，涵盖了任务列表在与 GTask 交互时创建、更新操作对应的 JSON 数据构建及解析，同步操作类型判断，以及对其包含的子任务（Task对象）的增删改查、位置移动、根据标识查找等一系列管理操作，同时还有自身索引属性的设置与获取功能，在构建具有层级结构的任务管理体系以及实现任务列表数据的同步、展示与操作等业务场景中起着关键作用。
+函数分析
+TaskList类构造函数
+所属类：TaskList
+功能：调用父类构造函数进行初始化后，创建一个空的ArrayList用于存储子任务（Task对象），并将自身索引属性（mIndex）初始化为1，为后续管理子任务及记录列表相关属性做准备。
+getCreateAction方法
+所属类：TaskList
+功能：创建一个新的JSONObject对象，按照 GTask 相关格式要求，向其中添加动作类型（创建）、动作ID、索引、任务列表实体相关数据（名称、创建者ID、类型等）等信息，若添加过程出现JSONException则记录错误日志、打印堆栈信息并抛出异常，最终返回构建好的用于创建任务列表的JSONObject，用于生成创建任务列表操作对应的 JSON 数据结构。
+getUpdateAction方法
+所属类：TaskList
+功能：同样先创建一个JSONObject对象，然后依据 GTask 规范，向其中添加动作类型（更新）、动作ID、任务列表ID以及任务列表实体更新相关的数据（名称、删除状态等），若出现JSONException则记录错误日志、打印堆栈信息并抛出异常，最后返回该JSONObject，用于构建任务列表更新操作对应的 JSON 数据内容。
+setContentByRemoteJSON方法
+所属类：TaskList
+功能：在传入的JSONObject不为null的前提下，尝试从其中获取并设置任务列表的相关属性信息，包括ID、最后修改时间、名称等，若获取过程出现JSONException则记录错误日志、打印堆栈信息并抛出异常，用于根据远程传来的 JSON 数据更新任务列表对象的属性内容。
+setContentByLocalJSON方法
+所属类：TaskList
+功能：先对传入的JSONObject进行有效性判断，若不符合要求则记录警告日志，若符合则尝试从中解析出笔记相关信息，根据笔记类型（文件夹类型、系统类型等）进行不同处理，设置任务列表的名称，用于依据本地 JSON 数据设置任务列表的名称等相关属性。
+getLocalJSONFromContent方法
+所属类：TaskList
+功能：创建一个新的JSONObject对象，按照特定格式从任务列表名称等信息中提取并构建包含笔记相关信息的JSONObject，添加到外层JSONObject中并返回，若过程中出现JSONException则记录错误日志、打印堆栈信息并返回null，用于生成基于任务列表当前内容的本地 JSON 数据表示形式。
+getSyncAction方法
+所属类：TaskList
+功能：通过判断本地是否有更新（依据LOCAL_MODIFIED_COLUMN的值）以及同步ID与最后修改时间是否匹配、GTask ID是否一致等条件，按照不同情况返回对应的同步操作类型常量（如无操作、本地更新、远程更新、出现错误等），若过程中出现异常则记录错误日志并打印堆栈信息，用于判断任务列表在数据同步过程中的操作类型。
+getChildTaskCount方法
+所属类：TaskList
+功能：返回存储子任务的ArrayList的大小，也就是任务列表中包含的子任务数量，用于获取任务列表中子任务的个数信息，便于展示、统计等业务操作。
+addChildTask(Task task)方法
+所属类：TaskList
+功能：判断传入的Task对象不为null且尚未包含在子任务列表中时，将其添加到子任务列表中，添加成功后设置该任务的前置任务（若列表为空则为null，否则为列表中最后一个任务）和父任务（当前任务列表），最后返回添加操作是否成功的布尔值，用于向任务列表中添加单个子任务并建立任务之间的关联关系。
+addChildTask(Task task, int index)方法
+所属类：TaskList
+功能：先对传入的索引参数进行合法性判断，若索引无效则记录错误日志并返回false。接着判断任务不为null且不在子任务列表中时，将其添加到指定索引位置，然后更新任务列表中相关任务的前置任务关系（设置新添加任务的前置任务以及其后续任务的前置任务），最后返回添加操作是否成功的布尔值，用于在指定位置向任务列表中添加子任务并正确维护任务间的顺序关系。
+removeChildTask(Task task)方法
+所属类：TaskList
+功能：先查找传入任务在子任务列表中的索引，若索引存在则从列表中移除该任务，移除成功后重置该任务的前置任务和父任务为null，同时更新任务列表中后续任务（若有）的前置任务关系，最后返回移除操作是否成功的布尔值，用于从任务列表中移除指定的子任务并调整相关任务关系。
+moveChildTask(Task task, int index)方法
+所属类：TaskList
+功能：先对目标索引进行合法性判断，若索引无效则记录错误日志并返回false；接着判断任务是否在任务列表中，若不在则同样记录错误日志并返回false；若任务所在位置与目标索引相同则直接返回true，否则先移除该任务再将其添加到目标索引位置，通过调用前面的相关方法实现任务在列表中的位置移动，最后返回移动操作是否成功的布尔值，用于在任务列表中移动指定子任务到新的位置。
+findChildTaskByGid(String gid)方法
+所属类：TaskList
+功能：遍历子任务列表，查找Gid属性与传入gid字符串相等的子任务，若找到则返回该任务，若遍历完未找到则返回null，用于根据任务的唯一标识（Gid）在任务列表中查找对应的子任务。
+getChildTaskIndex(Task task)方法
+所属类：TaskList
+功能：返回传入任务在子任务列表中的索引位置，若任务不在列表中则返回-1，用于获取子任务在任务列表中的位置信息，便于排序、查找等操作。
+getChildTaskByIndex(int index)方法
+所属类：TaskList
+功能：先对传入的索引参数进行合法性判断，若索引无效则记录错误日志并返回null，若合法则从子任务列表中获取并返回对应索引位置的子任务对象，用于根据索引获取任务列表中的指定子任务。
+getChilTaskByGid(String gid)方法
+所属类：TaskList
+功能：遍历子任务列表，查找Gid属性与传入gid字符串匹配的子任务，找到则返回该任务，若遍历完未找到则返回null，与findChildTaskByGid方法功能类似，同样用于根据任务标识查找对应的子任务。
+getChildTaskList方法
+所属类：TaskList
+功能：返回存储子任务的ArrayList对象，也就是获取任务列表包含的所有子任务列表，便于对所有子任务进行批量操作或获取相关信息等操作。
+setIndex(int index)方法
+所属类：TaskList
+功能：接收一个整数参数index，将其赋值给mIndex属性，用于更新任务列表的索引属性值，满足业务场景中对任务列表索引修改的需求。
+getIndex方法
+所属类：TaskList
+功能：返回mIndex属性的值，也就是获取任务列表当前的索引值，用于获取任务列表的索引相关信息，在展示、排序等场景下可能会用到。
+ */
+
+package net.micode.notes.gtask.data;
+
+import android.database.Cursor;
+import android.util.Log;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.gtask.exception.ActionFailureException;
+import net.micode.notes.tool.GTaskStringUtils;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.util.ArrayList;
+
+
+public class TaskList extends Node {
+    private static final String TAG = TaskList.class.getSimpleName();
+
+    private int mIndex;
+
+    private ArrayList<Task> mChildren;
+
+    public TaskList() {
+        super();
+        mChildren = new ArrayList<Task>();
+        mIndex = 1;
+    }
+
+    public JSONObject getCreateAction(int actionId) {
+        JSONObject js = new JSONObject();
+
+        try {
+            // action_type
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
+                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_CREATE);
+
+            // action_id
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, actionId);
+
+            // index
+            js.put(GTaskStringUtils.GTASK_JSON_INDEX, mIndex);
+
+            // entity_delta
+            JSONObject entity = new JSONObject();
+            entity.put(GTaskStringUtils.GTASK_JSON_NAME, getName());
+            entity.put(GTaskStringUtils.GTASK_JSON_CREATOR_ID, "null");
+            entity.put(GTaskStringUtils.GTASK_JSON_ENTITY_TYPE,
+                    GTaskStringUtils.GTASK_JSON_TYPE_GROUP);
+            js.put(GTaskStringUtils.GTASK_JSON_ENTITY_DELTA, entity);
+
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("fail to generate tasklist-create jsonobject");
+        }
+
+        return js;
+    }
+
+    public JSONObject getUpdateAction(int actionId) {
+        JSONObject js = new JSONObject();
+
+        try {
+            // action_type
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
+                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_UPDATE);
+
+            // action_id
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, actionId);
+
+            // id
+            js.put(GTaskStringUtils.GTASK_JSON_ID, getGid());
+
+            // entity_delta
+            JSONObject entity = new JSONObject();
+            entity.put(GTaskStringUtils.GTASK_JSON_NAME, getName());
+            entity.put(GTaskStringUtils.GTASK_JSON_DELETED, getDeleted());
+            js.put(GTaskStringUtils.GTASK_JSON_ENTITY_DELTA, entity);
+
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("fail to generate tasklist-update jsonobject");
+        }
+
+        return js;
+    }
+
+    public void setContentByRemoteJSON(JSONObject js) {
+        if (js != null) {
+            try {
+                // id
+                if (js.has(GTaskStringUtils.GTASK_JSON_ID)) {
+                    setGid(js.getString(GTaskStringUtils.GTASK_JSON_ID));
+                }
+
+                // last_modified
+                if (js.has(GTaskStringUtils.GTASK_JSON_LAST_MODIFIED)) {
+                    setLastModified(js.getLong(GTaskStringUtils.GTASK_JSON_LAST_MODIFIED));
+                }
+
+                // name
+                if (js.has(GTaskStringUtils.GTASK_JSON_NAME)) {
+                    setName(js.getString(GTaskStringUtils.GTASK_JSON_NAME));
+                }
+
+            } catch (JSONException e) {
+                Log.e(TAG, e.toString());
+                e.printStackTrace();
+                throw new ActionFailureException("fail to get tasklist content from jsonobject");
+            }
+        }
+    }
+
+    public void setContentByLocalJSON(JSONObject js) {
+        if (js == null || !js.has(GTaskStringUtils.META_HEAD_NOTE)) {
+            Log.w(TAG, "setContentByLocalJSON: nothing is avaiable");
+        }
+
+        try {
+            JSONObject folder = js.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+
+            if (folder.getInt(NoteColumns.TYPE) == Notes.TYPE_FOLDER) {
+                String name = folder.getString(NoteColumns.SNIPPET);
+                setName(GTaskStringUtils.MIUI_FOLDER_PREFFIX + name);
+            } else if (folder.getInt(NoteColumns.TYPE) == Notes.TYPE_SYSTEM) {
+                if (folder.getLong(NoteColumns.ID) == Notes.ID_ROOT_FOLDER)
+                    setName(GTaskStringUtils.MIUI_FOLDER_PREFFIX + GTaskStringUtils.FOLDER_DEFAULT);
+                else if (folder.getLong(NoteColumns.ID) == Notes.ID_CALL_RECORD_FOLDER)
+                    setName(GTaskStringUtils.MIUI_FOLDER_PREFFIX
+                            + GTaskStringUtils.FOLDER_CALL_NOTE);
+                else
+                    Log.e(TAG, "invalid system folder");
+            } else {
+                Log.e(TAG, "error type");
+            }
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+        }
+    }
+
+    public JSONObject getLocalJSONFromContent() {
+        try {
+            JSONObject js = new JSONObject();
+            JSONObject folder = new JSONObject();
+
+            String folderName = getName();
+            if (getName().startsWith(GTaskStringUtils.MIUI_FOLDER_PREFFIX))
+                folderName = folderName.substring(GTaskStringUtils.MIUI_FOLDER_PREFFIX.length(),
+                        folderName.length());
+            folder.put(NoteColumns.SNIPPET, folderName);
+            if (folderName.equals(GTaskStringUtils.FOLDER_DEFAULT)
+                    || folderName.equals(GTaskStringUtils.FOLDER_CALL_NOTE))
+                folder.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+            else
+                folder.put(NoteColumns.TYPE, Notes.TYPE_FOLDER);
+
+            js.put(GTaskStringUtils.META_HEAD_NOTE, folder);
+
+            return js;
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+    public int getSyncAction(Cursor c) {
+        try {
+            if (c.getInt(SqlNote.LOCAL_MODIFIED_COLUMN) == 0) {
+                // there is no local update
+                if (c.getLong(SqlNote.SYNC_ID_COLUMN) == getLastModified()) {
+                    // no update both side
+                    return SYNC_ACTION_NONE;
+                } else {
+                    // apply remote to local
+                    return SYNC_ACTION_UPDATE_LOCAL;
+                }
+            } else {
+                // validate gtask id
+                if (!c.getString(SqlNote.GTASK_ID_COLUMN).equals(getGid())) {
+                    Log.e(TAG, "gtask id doesn't match");
+                    return SYNC_ACTION_ERROR;
+                }
+                if (c.getLong(SqlNote.SYNC_ID_COLUMN) == getLastModified()) {
+                    // local modification only
+                    return SYNC_ACTION_UPDATE_REMOTE;
+                } else {
+                    // for folder conflicts, just apply local modification
+                    return SYNC_ACTION_UPDATE_REMOTE;
+                }
+            }
+        } catch (Exception e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+        }
+
+        return SYNC_ACTION_ERROR;
+    }
+
+    public int getChildTaskCount() {
+        return mChildren.size();
+    }
+
+    public boolean addChildTask(Task task) {
+        boolean ret = false;
+        if (task != null && !mChildren.contains(task)) {
+            ret = mChildren.add(task);
+            if (ret) {
+                // need to set prior sibling and parent
+                task.setPriorSibling(mChildren.isEmpty() ? null : mChildren
+                        .get(mChildren.size() - 1));
+                task.setParent(this);
+            }
+        }
+        return ret;
+    }
+
+    public boolean addChildTask(Task task, int index) {
+        if (index < 0 || index > mChildren.size()) {
+            Log.e(TAG, "add child task: invalid index");
+            return false;
+        }
+
+        int pos = mChildren.indexOf(task);
+        if (task != null && pos == -1) {
+            mChildren.add(index, task);
+
+            // update the task list
+            Task preTask = null;
+            Task afterTask = null;
+            if (index != 0)
+                preTask = mChildren.get(index - 1);
+            if (index != mChildren.size() - 1)
+                afterTask = mChildren.get(index + 1);
+
+            task.setPriorSibling(preTask);
+            if (afterTask != null)
+                afterTask.setPriorSibling(task);
+        }
+
+        return true;
+    }
+
+    public boolean removeChildTask(Task task) {
+        boolean ret = false;
+        int index = mChildren.indexOf(task);
+        if (index != -1) {
+            ret = mChildren.remove(task);
+
+            if (ret) {
+                // reset prior sibling and parent
+                task.setPriorSibling(null);
+                task.setParent(null);
+
+                // update the task list
+                if (index != mChildren.size()) {
+                    mChildren.get(index).setPriorSibling(
+                            index == 0 ? null : mChildren.get(index - 1));
+                }
+            }
+        }
+        return ret;
+    }
+
+    public boolean moveChildTask(Task task, int index) {
+
+        if (index < 0 || index >= mChildren.size()) {
+            Log.e(TAG, "move child task: invalid index");
+            return false;
+        }
+
+        int pos = mChildren.indexOf(task);
+        if (pos == -1) {
+            Log.e(TAG, "move child task: the task should in the list");
+            return false;
+        }
+
+        if (pos == index)
+            return true;
+        return (removeChildTask(task) && addChildTask(task, index));
+    }
+
+    public Task findChildTaskByGid(String gid) {
+        for (int i = 0; i < mChildren.size(); i++) {
+            Task t = mChildren.get(i);
+            if (t.getGid().equals(gid)) {
+                return t;
+            }
+        }
+        return null;
+    }
+
+    public int getChildTaskIndex(Task task) {
+        return mChildren.indexOf(task);
+    }
+
+    public Task getChildTaskByIndex(int index) {
+        if (index < 0 || index >= mChildren.size()) {
+            Log.e(TAG, "getTaskByIndex: invalid index");
+            return null;
+        }
+        return mChildren.get(index);
+    }
+
+    public Task getChilTaskByGid(String gid) {
+        for (Task task : mChildren) {
+            if (task.getGid().equals(gid))
+                return task;
+        }
+        return null;
+    }
+
+    public ArrayList<Task> getChildTaskList() {
+        return this.mChildren;
+    }
+
+    public void setIndex(int index) {
+        this.mIndex = index;
+    }
+
+    public int getIndex() {
+        return this.mIndex;
+    }
+}

java/net/micode/notes/gtask/exception/ActionFailureException.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.exception;
+
+public class ActionFailureException extends RuntimeException {
+    private static final long serialVersionUID = 4425249765923293627L;
+
+    public ActionFailureException() {
+        super();
+    }
+
+    public ActionFailureException(String paramString) {
+        super(paramString);
+    }
+
+    public ActionFailureException(String paramString, Throwable paramThrowable) {
+        super(paramString, paramThrowable);
+    }
+}

java/net/micode/notes/gtask/exception/NetworkFailureException.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.exception;
+
+public class NetworkFailureException extends Exception {
+    private static final long serialVersionUID = 2107610287180234136L;
+
+    public NetworkFailureException() {
+        super();
+    }
+
+    public NetworkFailureException(String paramString) {
+        super(paramString);
+    }
+
+    public NetworkFailureException(String paramString, Throwable paramThrowable) {
+        super(paramString, paramThrowable);
+    }
+}

java/net/micode/notes/gtask/remote/GTaskASyncTask.java

@@ -0,0 +1,124 @@
+
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.remote;
+
+import android.app.Notification;
+import android.app.NotificationManager;
+import android.app.PendingIntent;
+import android.content.Context;
+import android.content.Intent;
+import android.os.AsyncTask;
+
+import net.micode.notes.R;
+import net.micode.notes.ui.NotesListActivity;
+import net.micode.notes.ui.NotesPreferenceActivity;
+
+
+public class GTaskASyncTask extends AsyncTask<Void, String, Integer> {
+
+    private static int GTASK_SYNC_NOTIFICATION_ID = 5234235;
+
+    public interface OnCompleteListener {
+        void onComplete();
+    }
+
+    private Context mContext;
+
+    private NotificationManager mNotifiManager;
+
+    private GTaskManager mTaskManager;
+
+    private OnCompleteListener mOnCompleteListener;
+
+    public GTaskASyncTask(Context context, OnCompleteListener listener) {
+        mContext = context;
+        mOnCompleteListener = listener;
+        mNotifiManager = (NotificationManager) mContext
+                .getSystemService(Context.NOTIFICATION_SERVICE);
+        mTaskManager = GTaskManager.getInstance();
+    }
+
+    public void cancelSync() {
+        mTaskManager.cancelSync();
+    }
+
+    public void publishProgess(String message) {
+        publishProgress(new String[] {
+            message
+        });
+    }
+
+    private void showNotification(int tickerId, String content) {
+        PendingIntent pendingIntent;
+        if (tickerId != R.string.ticker_success) {
+            pendingIntent = PendingIntent.getActivity(mContext, 0, new Intent(mContext,
+                    NotesPreferenceActivity.class), PendingIntent.FLAG_IMMUTABLE);
+        } else {
+            pendingIntent = PendingIntent.getActivity(mContext, 0, new Intent(mContext,
+                    NotesListActivity.class), PendingIntent.FLAG_IMMUTABLE);
+        }
+        Notification.Builder builder = new Notification.Builder(mContext)
+                .setAutoCancel(true)
+                .setContentTitle(mContext.getString(R.string.app_name))
+                .setContentText(content)
+                .setContentIntent(pendingIntent)
+                .setWhen(System.currentTimeMillis())
+                .setOngoing(true);
+        Notification notification=builder.getNotification();
+        mNotifiManager.notify(GTASK_SYNC_NOTIFICATION_ID, notification);
+    }
+
+    @Override
+    protected Integer doInBackground(Void... unused) {
+        publishProgess(mContext.getString(R.string.sync_progress_login, NotesPreferenceActivity
+                .getSyncAccountName(mContext)));
+        return mTaskManager.sync(mContext, this);
+    }
+
+    @Override
+    protected void onProgressUpdate(String... progress) {
+        showNotification(R.string.ticker_syncing, progress[0]);
+        if (mContext instanceof GTaskSyncService) {
+            ((GTaskSyncService) mContext).sendBroadcast(progress[0]);
+        }
+    }
+
+    @Override
+    protected void onPostExecute(Integer result) {
+        if (result == GTaskManager.STATE_SUCCESS) {
+            showNotification(R.string.ticker_success, mContext.getString(
+                    R.string.success_sync_account, mTaskManager.getSyncAccount()));
+            NotesPreferenceActivity.setLastSyncTime(mContext, System.currentTimeMillis());
+        } else if (result == GTaskManager.STATE_NETWORK_ERROR) {
+            showNotification(R.string.ticker_fail, mContext.getString(R.string.error_sync_network));
+        } else if (result == GTaskManager.STATE_INTERNAL_ERROR) {
+            showNotification(R.string.ticker_fail, mContext.getString(R.string.error_sync_internal));
+        } else if (result == GTaskManager.STATE_SYNC_CANCELLED) {
+            showNotification(R.string.ticker_cancel, mContext
+                    .getString(R.string.error_sync_cancelled));
+        }
+        if (mOnCompleteListener != null) {
+            new Thread(new Runnable() {
+
+                public void run() {
+                    mOnCompleteListener.onComplete();
+                }
+            }).start();
+        }
+    }
+}

java/net/micode/notes/gtask/remote/GTaskClient.java

@@ -0,0 +1,585 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.remote;
+
+import android.accounts.Account;
+import android.accounts.AccountManager;
+import android.accounts.AccountManagerFuture;
+import android.app.Activity;
+import android.os.Bundle;
+import android.text.TextUtils;
+import android.util.Log;
+
+import net.micode.notes.gtask.data.Node;
+import net.micode.notes.gtask.data.Task;
+import net.micode.notes.gtask.data.TaskList;
+import net.micode.notes.gtask.exception.ActionFailureException;
+import net.micode.notes.gtask.exception.NetworkFailureException;
+import net.micode.notes.tool.GTaskStringUtils;
+import net.micode.notes.ui.NotesPreferenceActivity;
+
+import org.apache.http.HttpEntity;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.ClientProtocolException;
+import org.apache.http.client.entity.UrlEncodedFormEntity;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.cookie.Cookie;
+import org.apache.http.impl.client.BasicCookieStore;
+import org.apache.http.impl.client.DefaultHttpClient;
+import org.apache.http.message.BasicNameValuePair;
+import org.apache.http.params.BasicHttpParams;
+import org.apache.http.params.HttpConnectionParams;
+import org.apache.http.params.HttpParams;
+import org.apache.http.params.HttpProtocolParams;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.zip.GZIPInputStream;
+import java.util.zip.Inflater;
+import java.util.zip.InflaterInputStream;
+
+
+public class GTaskClient {
+    private static final String TAG = GTaskClient.class.getSimpleName();
+
+    private static final String GTASK_URL = "https://mail.google.com/tasks/";
+
+    private static final String GTASK_GET_URL = "https://mail.google.com/tasks/ig";
+
+    private static final String GTASK_POST_URL = "https://mail.google.com/tasks/r/ig";
+
+    private static GTaskClient mInstance = null;
+
+    private DefaultHttpClient mHttpClient;
+
+    private String mGetUrl;
+
+    private String mPostUrl;
+
+    private long mClientVersion;
+
+    private boolean mLoggedin;
+
+    private long mLastLoginTime;
+
+    private int mActionId;
+
+    private Account mAccount;
+
+    private JSONArray mUpdateArray;
+
+    private GTaskClient() {
+        mHttpClient = null;
+        mGetUrl = GTASK_GET_URL;
+        mPostUrl = GTASK_POST_URL;
+        mClientVersion = -1;
+        mLoggedin = false;
+        mLastLoginTime = 0;
+        mActionId = 1;
+        mAccount = null;
+        mUpdateArray = null;
+    }
+
+    public static synchronized GTaskClient getInstance() {
+        if (mInstance == null) {
+            mInstance = new GTaskClient();
+        }
+        return mInstance;
+    }
+
+    public boolean login(Activity activity) {
+        // we suppose that the cookie would expire after 5 minutes
+        // then we need to re-login
+        final long interval = 1000 * 60 * 5;
+        if (mLastLoginTime + interval < System.currentTimeMillis()) {
+            mLoggedin = false;
+        }
+
+        // need to re-login after account switch
+        if (mLoggedin
+                && !TextUtils.equals(getSyncAccount().name, NotesPreferenceActivity
+                        .getSyncAccountName(activity))) {
+            mLoggedin = false;
+        }
+
+        if (mLoggedin) {
+            Log.d(TAG, "already logged in");
+            return true;
+        }
+
+        mLastLoginTime = System.currentTimeMillis();
+        String authToken = loginGoogleAccount(activity, false);
+        if (authToken == null) {
+            Log.e(TAG, "login google account failed");
+            return false;
+        }
+
+        // login with custom domain if necessary
+        if (!(mAccount.name.toLowerCase().endsWith("gmail.com") || mAccount.name.toLowerCase()
+                .endsWith("googlemail.com"))) {
+            StringBuilder url = new StringBuilder(GTASK_URL).append("a/");
+            int index = mAccount.name.indexOf('@') + 1;
+            String suffix = mAccount.name.substring(index);
+            url.append(suffix + "/");
+            mGetUrl = url.toString() + "ig";
+            mPostUrl = url.toString() + "r/ig";
+
+            if (tryToLoginGtask(activity, authToken)) {
+                mLoggedin = true;
+            }
+        }
+
+        // try to login with google official url
+        if (!mLoggedin) {
+            mGetUrl = GTASK_GET_URL;
+            mPostUrl = GTASK_POST_URL;
+            if (!tryToLoginGtask(activity, authToken)) {
+                return false;
+            }
+        }
+
+        mLoggedin = true;
+        return true;
+    }
+
+    private String loginGoogleAccount(Activity activity, boolean invalidateToken) {
+        String authToken;
+        AccountManager accountManager = AccountManager.get(activity);
+        Account[] accounts = accountManager.getAccountsByType("com.google");
+
+        if (accounts.length == 0) {
+            Log.e(TAG, "there is no available google account");
+            return null;
+        }
+
+        String accountName = NotesPreferenceActivity.getSyncAccountName(activity);
+        Account account = null;
+        for (Account a : accounts) {
+            if (a.name.equals(accountName)) {
+                account = a;
+                break;
+            }
+        }
+        if (account != null) {
+            mAccount = account;
+        } else {
+            Log.e(TAG, "unable to get an account with the same name in the settings");
+            return null;
+        }
+
+        // get the token now
+        AccountManagerFuture<Bundle> accountManagerFuture = accountManager.getAuthToken(account,
+                "goanna_mobile", null, activity, null, null);
+        try {
+            Bundle authTokenBundle = accountManagerFuture.getResult();
+            authToken = authTokenBundle.getString(AccountManager.KEY_AUTHTOKEN);
+            if (invalidateToken) {
+                accountManager.invalidateAuthToken("com.google", authToken);
+                loginGoogleAccount(activity, false);
+            }
+        } catch (Exception e) {
+            Log.e(TAG, "get auth token failed");
+            authToken = null;
+        }
+
+        return authToken;
+    }
+
+    private boolean tryToLoginGtask(Activity activity, String authToken) {
+        if (!loginGtask(authToken)) {
+            // maybe the auth token is out of date, now let's invalidate the
+            // token and try again
+            authToken = loginGoogleAccount(activity, true);
+            if (authToken == null) {
+                Log.e(TAG, "login google account failed");
+                return false;
+            }
+
+            if (!loginGtask(authToken)) {
+                Log.e(TAG, "login gtask failed");
+                return false;
+            }
+        }
+        return true;
+    }
+
+    private boolean loginGtask(String authToken) {
+        int timeoutConnection = 10000;
+        int timeoutSocket = 15000;
+        HttpParams httpParameters = new BasicHttpParams();
+        HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
+        HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
+        mHttpClient = new DefaultHttpClient(httpParameters);
+        BasicCookieStore localBasicCookieStore = new BasicCookieStore();
+        mHttpClient.setCookieStore(localBasicCookieStore);
+        HttpProtocolParams.setUseExpectContinue(mHttpClient.getParams(), false);
+
+        // login gtask
+        try {
+            String loginUrl = mGetUrl + "?auth=" + authToken;
+            HttpGet httpGet = new HttpGet(loginUrl);
+            HttpResponse response = null;
+            response = mHttpClient.execute(httpGet);
+
+            // get the cookie now
+            List<Cookie> cookies = mHttpClient.getCookieStore().getCookies();
+            boolean hasAuthCookie = false;
+            for (Cookie cookie : cookies) {
+                if (cookie.getName().contains("GTL")) {
+                    hasAuthCookie = true;
+                }
+            }
+            if (!hasAuthCookie) {
+                Log.w(TAG, "it seems that there is no auth cookie");
+            }
+
+            // get the client version
+            String resString = getResponseContent(response.getEntity());
+            String jsBegin = "_setup(";
+            String jsEnd = ")}</script>";
+            int begin = resString.indexOf(jsBegin);
+            int end = resString.lastIndexOf(jsEnd);
+            String jsString = null;
+            if (begin != -1 && end != -1 && begin < end) {
+                jsString = resString.substring(begin + jsBegin.length(), end);
+            }
+            JSONObject js = new JSONObject(jsString);
+            mClientVersion = js.getLong("v");
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            return false;
+        } catch (Exception e) {
+            // simply catch all exceptions
+            Log.e(TAG, "httpget gtask_url failed");
+            return false;
+        }
+
+        return true;
+    }
+
+    private int getActionId() {
+        return mActionId++;
+    }
+
+    private HttpPost createHttpPost() {
+        HttpPost httpPost = new HttpPost(mPostUrl);
+        httpPost.setHeader("Content-Type", "application/x-www-form-urlencoded;charset=utf-8");
+        httpPost.setHeader("AT", "1");
+        return httpPost;
+    }
+
+    private String getResponseContent(HttpEntity entity) throws IOException {
+        String contentEncoding = null;
+        if (entity.getContentEncoding() != null) {
+            contentEncoding = entity.getContentEncoding().getValue();
+            Log.d(TAG, "encoding: " + contentEncoding);
+        }
+
+        InputStream input = entity.getContent();
+        if (contentEncoding != null && contentEncoding.equalsIgnoreCase("gzip")) {
+            input = new GZIPInputStream(entity.getContent());
+        } else if (contentEncoding != null && contentEncoding.equalsIgnoreCase("deflate")) {
+            Inflater inflater = new Inflater(true);
+            input = new InflaterInputStream(entity.getContent(), inflater);
+        }
+
+        try {
+            InputStreamReader isr = new InputStreamReader(input);
+            BufferedReader br = new BufferedReader(isr);
+            StringBuilder sb = new StringBuilder();
+
+            while (true) {
+                String buff = br.readLine();
+                if (buff == null) {
+                    return sb.toString();
+                }
+                sb = sb.append(buff);
+            }
+        } finally {
+            input.close();
+        }
+    }
+
+    private JSONObject postRequest(JSONObject js) throws NetworkFailureException {
+        if (!mLoggedin) {
+            Log.e(TAG, "please login first");
+            throw new ActionFailureException("not logged in");
+        }
+
+        HttpPost httpPost = createHttpPost();
+        try {
+            LinkedList<BasicNameValuePair> list = new LinkedList<BasicNameValuePair>();
+            list.add(new BasicNameValuePair("r", js.toString()));
+            UrlEncodedFormEntity entity = new UrlEncodedFormEntity(list, "UTF-8");
+            httpPost.setEntity(entity);
+
+            // execute the post
+            HttpResponse response = mHttpClient.execute(httpPost);
+            String jsString = getResponseContent(response.getEntity());
+            return new JSONObject(jsString);
+
+        } catch (ClientProtocolException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new NetworkFailureException("postRequest failed");
+        } catch (IOException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new NetworkFailureException("postRequest failed");
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("unable to convert response content to jsonobject");
+        } catch (Exception e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("error occurs when posting request");
+        }
+    }
+
+    public void createTask(Task task) throws NetworkFailureException {
+        commitUpdate();
+        try {
+            JSONObject jsPost = new JSONObject();
+            JSONArray actionList = new JSONArray();
+
+            // action_list
+            actionList.put(task.getCreateAction(getActionId()));
+            jsPost.put(GTaskStringUtils.GTASK_JSON_ACTION_LIST, actionList);
+
+            // client_version
+            jsPost.put(GTaskStringUtils.GTASK_JSON_CLIENT_VERSION, mClientVersion);
+
+            // post
+            JSONObject jsResponse = postRequest(jsPost);
+            JSONObject jsResult = (JSONObject) jsResponse.getJSONArray(
+                    GTaskStringUtils.GTASK_JSON_RESULTS).get(0);
+            task.setGid(jsResult.getString(GTaskStringUtils.GTASK_JSON_NEW_ID));
+
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("create task: handing jsonobject failed");
+        }
+    }
+
+    public void createTaskList(TaskList tasklist) throws NetworkFailureException {
+        commitUpdate();
+        try {
+            JSONObject jsPost = new JSONObject();
+            JSONArray actionList = new JSONArray();
+
+            // action_list
+            actionList.put(tasklist.getCreateAction(getActionId()));
+            jsPost.put(GTaskStringUtils.GTASK_JSON_ACTION_LIST, actionList);
+
+            // client version
+            jsPost.put(GTaskStringUtils.GTASK_JSON_CLIENT_VERSION, mClientVersion);
+
+            // post
+            JSONObject jsResponse = postRequest(jsPost);
+            JSONObject jsResult = (JSONObject) jsResponse.getJSONArray(
+                    GTaskStringUtils.GTASK_JSON_RESULTS).get(0);
+            tasklist.setGid(jsResult.getString(GTaskStringUtils.GTASK_JSON_NEW_ID));
+
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("create tasklist: handing jsonobject failed");
+        }
+    }
+
+    public void commitUpdate() throws NetworkFailureException {
+        if (mUpdateArray != null) {
+            try {
+                JSONObject jsPost = new JSONObject();
+
+                // action_list
+                jsPost.put(GTaskStringUtils.GTASK_JSON_ACTION_LIST, mUpdateArray);
+
+                // client_version
+                jsPost.put(GTaskStringUtils.GTASK_JSON_CLIENT_VERSION, mClientVersion);
+
+                postRequest(jsPost);
+                mUpdateArray = null;
+            } catch (JSONException e) {
+                Log.e(TAG, e.toString());
+                e.printStackTrace();
+                throw new ActionFailureException("commit update: handing jsonobject failed");
+            }
+        }
+    }
+
+    public void addUpdateNode(Node node) throws NetworkFailureException {
+        if (node != null) {
+            // too many update items may result in an error
+            // set max to 10 items
+            if (mUpdateArray != null && mUpdateArray.length() > 10) {
+                commitUpdate();
+            }
+
+            if (mUpdateArray == null)
+                mUpdateArray = new JSONArray();
+            mUpdateArray.put(node.getUpdateAction(getActionId()));
+        }
+    }
+
+    public void moveTask(Task task, TaskList preParent, TaskList curParent)
+            throws NetworkFailureException {
+        commitUpdate();
+        try {
+            JSONObject jsPost = new JSONObject();
+            JSONArray actionList = new JSONArray();
+            JSONObject action = new JSONObject();
+
+            // action_list
+            action.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
+                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_MOVE);
+            action.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, getActionId());
+            action.put(GTaskStringUtils.GTASK_JSON_ID, task.getGid());
+            if (preParent == curParent && task.getPriorSibling() != null) {
+                // put prioring_sibing_id only if moving within the tasklist and
+                // it is not the first one
+                action.put(GTaskStringUtils.GTASK_JSON_PRIOR_SIBLING_ID, task.getPriorSibling());
+            }
+            action.put(GTaskStringUtils.GTASK_JSON_SOURCE_LIST, preParent.getGid());
+            action.put(GTaskStringUtils.GTASK_JSON_DEST_PARENT, curParent.getGid());
+            if (preParent != curParent) {
+                // put the dest_list only if moving between tasklists
+                action.put(GTaskStringUtils.GTASK_JSON_DEST_LIST, curParent.getGid());
+            }
+            actionList.put(action);
+            jsPost.put(GTaskStringUtils.GTASK_JSON_ACTION_LIST, actionList);
+
+            // client_version
+            jsPost.put(GTaskStringUtils.GTASK_JSON_CLIENT_VERSION, mClientVersion);
+
+            postRequest(jsPost);
+
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("move task: handing jsonobject failed");
+        }
+    }
+
+    public void deleteNode(Node node) throws NetworkFailureException {
+        commitUpdate();
+        try {
+            JSONObject jsPost = new JSONObject();
+            JSONArray actionList = new JSONArray();
+
+            // action_list
+            node.setDeleted(true);
+            actionList.put(node.getUpdateAction(getActionId()));
+            jsPost.put(GTaskStringUtils.GTASK_JSON_ACTION_LIST, actionList);
+
+            // client_version
+            jsPost.put(GTaskStringUtils.GTASK_JSON_CLIENT_VERSION, mClientVersion);
+
+            postRequest(jsPost);
+            mUpdateArray = null;
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("delete node: handing jsonobject failed");
+        }
+    }
+
+    public JSONArray getTaskLists() throws NetworkFailureException {
+        if (!mLoggedin) {
+            Log.e(TAG, "please login first");
+            throw new ActionFailureException("not logged in");
+        }
+
+        try {
+            HttpGet httpGet = new HttpGet(mGetUrl);
+            HttpResponse response = null;
+            response = mHttpClient.execute(httpGet);
+
+            // get the task list
+            String resString = getResponseContent(response.getEntity());
+            String jsBegin = "_setup(";
+            String jsEnd = ")}</script>";
+            int begin = resString.indexOf(jsBegin);
+            int end = resString.lastIndexOf(jsEnd);
+            String jsString = null;
+            if (begin != -1 && end != -1 && begin < end) {
+                jsString = resString.substring(begin + jsBegin.length(), end);
+            }
+            JSONObject js = new JSONObject(jsString);
+            return js.getJSONObject("t").getJSONArray(GTaskStringUtils.GTASK_JSON_LISTS);
+        } catch (ClientProtocolException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new NetworkFailureException("gettasklists: httpget failed");
+        } catch (IOException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new NetworkFailureException("gettasklists: httpget failed");
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("get task lists: handing jasonobject failed");
+        }
+    }
+
+    public JSONArray getTaskList(String listGid) throws NetworkFailureException {
+        commitUpdate();
+        try {
+            JSONObject jsPost = new JSONObject();
+            JSONArray actionList = new JSONArray();
+            JSONObject action = new JSONObject();
+
+            // action_list
+            action.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
+                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_GETALL);
+            action.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, getActionId());
+            action.put(GTaskStringUtils.GTASK_JSON_LIST_ID, listGid);
+            action.put(GTaskStringUtils.GTASK_JSON_GET_DELETED, false);
+            actionList.put(action);
+            jsPost.put(GTaskStringUtils.GTASK_JSON_ACTION_LIST, actionList);
+
+            // client_version
+            jsPost.put(GTaskStringUtils.GTASK_JSON_CLIENT_VERSION, mClientVersion);
+
+            JSONObject jsResponse = postRequest(jsPost);
+            return jsResponse.getJSONArray(GTaskStringUtils.GTASK_JSON_TASKS);
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("get task list: handing jsonobject failed");
+        }
+    }
+
+    public Account getSyncAccount() {
+        return mAccount;
+    }
+
+    public void resetUpdateArray() {
+        mUpdateArray = null;
+    }
+}

java/net/micode/notes/gtask/remote/GTaskManager.java

@@ -0,0 +1,800 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.remote;
+
+import android.app.Activity;
+import android.content.ContentResolver;
+import android.content.ContentUris;
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.Cursor;
+import android.util.Log;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.gtask.data.MetaData;
+import net.micode.notes.gtask.data.Node;
+import net.micode.notes.gtask.data.SqlNote;
+import net.micode.notes.gtask.data.Task;
+import net.micode.notes.gtask.data.TaskList;
+import net.micode.notes.gtask.exception.ActionFailureException;
+import net.micode.notes.gtask.exception.NetworkFailureException;
+import net.micode.notes.tool.DataUtils;
+import net.micode.notes.tool.GTaskStringUtils;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Map;
+
+
+public class GTaskManager {
+    private static final String TAG = GTaskManager.class.getSimpleName();
+
+    public static final int STATE_SUCCESS = 0;
+
+    public static final int STATE_NETWORK_ERROR = 1;
+
+    public static final int STATE_INTERNAL_ERROR = 2;
+
+    public static final int STATE_SYNC_IN_PROGRESS = 3;
+
+    public static final int STATE_SYNC_CANCELLED = 4;
+
+    private static GTaskManager mInstance = null;
+
+    private Activity mActivity;
+
+    private Context mContext;
+
+    private ContentResolver mContentResolver;
+
+    private boolean mSyncing;
+
+    private boolean mCancelled;
+
+    private HashMap<String, TaskList> mGTaskListHashMap;
+
+    private HashMap<String, Node> mGTaskHashMap;
+
+    private HashMap<String, MetaData> mMetaHashMap;
+
+    private TaskList mMetaList;
+
+    private HashSet<Long> mLocalDeleteIdMap;
+
+    private HashMap<String, Long> mGidToNid;
+
+    private HashMap<Long, String> mNidToGid;
+
+    private GTaskManager() {
+        mSyncing = false;
+        mCancelled = false;
+        mGTaskListHashMap = new HashMap<String, TaskList>();
+        mGTaskHashMap = new HashMap<String, Node>();
+        mMetaHashMap = new HashMap<String, MetaData>();
+        mMetaList = null;
+        mLocalDeleteIdMap = new HashSet<Long>();
+        mGidToNid = new HashMap<String, Long>();
+        mNidToGid = new HashMap<Long, String>();
+    }
+
+    public static synchronized GTaskManager getInstance() {
+        if (mInstance == null) {
+            mInstance = new GTaskManager();
+        }
+        return mInstance;
+    }
+
+    public synchronized void setActivityContext(Activity activity) {
+        // used for getting authtoken
+        mActivity = activity;
+    }
+
+    public int sync(Context context, GTaskASyncTask asyncTask) {
+        if (mSyncing) {
+            Log.d(TAG, "Sync is in progress");
+            return STATE_SYNC_IN_PROGRESS;
+        }
+        mContext = context;
+        mContentResolver = mContext.getContentResolver();
+        mSyncing = true;
+        mCancelled = false;
+        mGTaskListHashMap.clear();
+        mGTaskHashMap.clear();
+        mMetaHashMap.clear();
+        mLocalDeleteIdMap.clear();
+        mGidToNid.clear();
+        mNidToGid.clear();
+
+        try {
+            GTaskClient client = GTaskClient.getInstance();
+            client.resetUpdateArray();
+
+            // login google task
+            if (!mCancelled) {
+                if (!client.login(mActivity)) {
+                    throw new NetworkFailureException("login google task failed");
+                }
+            }
+
+            // get the task list from google
+            asyncTask.publishProgess(mContext.getString(R.string.sync_progress_init_list));
+            initGTaskList();
+
+            // do content sync work
+            asyncTask.publishProgess(mContext.getString(R.string.sync_progress_syncing));
+            syncContent();
+        } catch (NetworkFailureException e) {
+            Log.e(TAG, e.toString());
+            return STATE_NETWORK_ERROR;
+        } catch (ActionFailureException e) {
+            Log.e(TAG, e.toString());
+            return STATE_INTERNAL_ERROR;
+        } catch (Exception e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            return STATE_INTERNAL_ERROR;
+        } finally {
+            mGTaskListHashMap.clear();
+            mGTaskHashMap.clear();
+            mMetaHashMap.clear();
+            mLocalDeleteIdMap.clear();
+            mGidToNid.clear();
+            mNidToGid.clear();
+            mSyncing = false;
+        }
+
+        return mCancelled ? STATE_SYNC_CANCELLED : STATE_SUCCESS;
+    }
+
+    private void initGTaskList() throws NetworkFailureException {
+        if (mCancelled)
+            return;
+        GTaskClient client = GTaskClient.getInstance();
+        try {
+            JSONArray jsTaskLists = client.getTaskLists();
+
+            // init meta list first
+            mMetaList = null;
+            for (int i = 0; i < jsTaskLists.length(); i++) {
+                JSONObject object = jsTaskLists.getJSONObject(i);
+                String gid = object.getString(GTaskStringUtils.GTASK_JSON_ID);
+                String name = object.getString(GTaskStringUtils.GTASK_JSON_NAME);
+
+                if (name
+                        .equals(GTaskStringUtils.MIUI_FOLDER_PREFFIX + GTaskStringUtils.FOLDER_META)) {
+                    mMetaList = new TaskList();
+                    mMetaList.setContentByRemoteJSON(object);
+
+                    // load meta data
+                    JSONArray jsMetas = client.getTaskList(gid);
+                    for (int j = 0; j < jsMetas.length(); j++) {
+                        object = (JSONObject) jsMetas.getJSONObject(j);
+                        MetaData metaData = new MetaData();
+                        metaData.setContentByRemoteJSON(object);
+                        if (metaData.isWorthSaving()) {
+                            mMetaList.addChildTask(metaData);
+                            if (metaData.getGid() != null) {
+                                mMetaHashMap.put(metaData.getRelatedGid(), metaData);
+                            }
+                        }
+                    }
+                }
+            }
+
+            // create meta list if not existed
+            if (mMetaList == null) {
+                mMetaList = new TaskList();
+                mMetaList.setName(GTaskStringUtils.MIUI_FOLDER_PREFFIX
+                        + GTaskStringUtils.FOLDER_META);
+                GTaskClient.getInstance().createTaskList(mMetaList);
+            }
+
+            // init task list
+            for (int i = 0; i < jsTaskLists.length(); i++) {
+                JSONObject object = jsTaskLists.getJSONObject(i);
+                String gid = object.getString(GTaskStringUtils.GTASK_JSON_ID);
+                String name = object.getString(GTaskStringUtils.GTASK_JSON_NAME);
+
+                if (name.startsWith(GTaskStringUtils.MIUI_FOLDER_PREFFIX)
+                        && !name.equals(GTaskStringUtils.MIUI_FOLDER_PREFFIX
+                                + GTaskStringUtils.FOLDER_META)) {
+                    TaskList tasklist = new TaskList();
+                    tasklist.setContentByRemoteJSON(object);
+                    mGTaskListHashMap.put(gid, tasklist);
+                    mGTaskHashMap.put(gid, tasklist);
+
+                    // load tasks
+                    JSONArray jsTasks = client.getTaskList(gid);
+                    for (int j = 0; j < jsTasks.length(); j++) {
+                        object = (JSONObject) jsTasks.getJSONObject(j);
+                        gid = object.getString(GTaskStringUtils.GTASK_JSON_ID);
+                        Task task = new Task();
+                        task.setContentByRemoteJSON(object);
+                        if (task.isWorthSaving()) {
+                            task.setMetaInfo(mMetaHashMap.get(gid));
+                            tasklist.addChildTask(task);
+                            mGTaskHashMap.put(gid, task);
+                        }
+                    }
+                }
+            }
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("initGTaskList: handing JSONObject failed");
+        }
+    }
+
+    private void syncContent() throws NetworkFailureException {
+        int syncType;
+        Cursor c = null;
+        String gid;
+        Node node;
+
+        mLocalDeleteIdMap.clear();
+
+        if (mCancelled) {
+            return;
+        }
+
+        // for local deleted note
+        try {
+            c = mContentResolver.query(Notes.CONTENT_NOTE_URI, SqlNote.PROJECTION_NOTE,
+                    "(type<>? AND parent_id=?)", new String[] {
+                            String.valueOf(Notes.TYPE_SYSTEM), String.valueOf(Notes.ID_TRASH_FOLER)
+                    }, null);
+            if (c != null) {
+                while (c.moveToNext()) {
+                    gid = c.getString(SqlNote.GTASK_ID_COLUMN);
+                    node = mGTaskHashMap.get(gid);
+                    if (node != null) {
+                        mGTaskHashMap.remove(gid);
+                        doContentSync(Node.SYNC_ACTION_DEL_REMOTE, node, c);
+                    }
+
+                    mLocalDeleteIdMap.add(c.getLong(SqlNote.ID_COLUMN));
+                }
+            } else {
+                Log.w(TAG, "failed to query trash folder");
+            }
+        } finally {
+            if (c != null) {
+                c.close();
+                c = null;
+            }
+        }
+
+        // sync folder first
+        syncFolder();
+
+        // for note existing in database
+        try {
+            c = mContentResolver.query(Notes.CONTENT_NOTE_URI, SqlNote.PROJECTION_NOTE,
+                    "(type=? AND parent_id<>?)", new String[] {
+                            String.valueOf(Notes.TYPE_NOTE), String.valueOf(Notes.ID_TRASH_FOLER)
+                    }, NoteColumns.TYPE + " DESC");
+            if (c != null) {
+                while (c.moveToNext()) {
+                    gid = c.getString(SqlNote.GTASK_ID_COLUMN);
+                    node = mGTaskHashMap.get(gid);
+                    if (node != null) {
+                        mGTaskHashMap.remove(gid);
+                        mGidToNid.put(gid, c.getLong(SqlNote.ID_COLUMN));
+                        mNidToGid.put(c.getLong(SqlNote.ID_COLUMN), gid);
+                        syncType = node.getSyncAction(c);
+                    } else {
+                        if (c.getString(SqlNote.GTASK_ID_COLUMN).trim().length() == 0) {
+                            // local add
+                            syncType = Node.SYNC_ACTION_ADD_REMOTE;
+                        } else {
+                            // remote delete
+                            syncType = Node.SYNC_ACTION_DEL_LOCAL;
+                        }
+                    }
+                    doContentSync(syncType, node, c);
+                }
+            } else {
+                Log.w(TAG, "failed to query existing note in database");
+            }
+
+        } finally {
+            if (c != null) {
+                c.close();
+                c = null;
+            }
+        }
+
+        // go through remaining items
+        Iterator<Map.Entry<String, Node>> iter = mGTaskHashMap.entrySet().iterator();
+        while (iter.hasNext()) {
+            Map.Entry<String, Node> entry = iter.next();
+            node = entry.getValue();
+            doContentSync(Node.SYNC_ACTION_ADD_LOCAL, node, null);
+        }
+
+        // mCancelled can be set by another thread, so we neet to check one by
+        // one
+        // clear local delete table
+        if (!mCancelled) {
+            if (!DataUtils.batchDeleteNotes(mContentResolver, mLocalDeleteIdMap)) {
+                throw new ActionFailureException("failed to batch-delete local deleted notes");
+            }
+        }
+
+        // refresh local sync id
+        if (!mCancelled) {
+            GTaskClient.getInstance().commitUpdate();
+            refreshLocalSyncId();
+        }
+
+    }
+
+    private void syncFolder() throws NetworkFailureException {
+        Cursor c = null;
+        String gid;
+        Node node;
+        int syncType;
+
+        if (mCancelled) {
+            return;
+        }
+
+        // for root folder
+        try {
+            c = mContentResolver.query(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI,
+                    Notes.ID_ROOT_FOLDER), SqlNote.PROJECTION_NOTE, null, null, null);
+            if (c != null) {
+                c.moveToNext();
+                gid = c.getString(SqlNote.GTASK_ID_COLUMN);
+                node = mGTaskHashMap.get(gid);
+                if (node != null) {
+                    mGTaskHashMap.remove(gid);
+                    mGidToNid.put(gid, (long) Notes.ID_ROOT_FOLDER);
+                    mNidToGid.put((long) Notes.ID_ROOT_FOLDER, gid);
+                    // for system folder, only update remote name if necessary
+                    if (!node.getName().equals(
+                            GTaskStringUtils.MIUI_FOLDER_PREFFIX + GTaskStringUtils.FOLDER_DEFAULT))
+                        doContentSync(Node.SYNC_ACTION_UPDATE_REMOTE, node, c);
+                } else {
+                    doContentSync(Node.SYNC_ACTION_ADD_REMOTE, node, c);
+                }
+            } else {
+                Log.w(TAG, "failed to query root folder");
+            }
+        } finally {
+            if (c != null) {
+                c.close();
+                c = null;
+            }
+        }
+
+        // for call-note folder
+        try {
+            c = mContentResolver.query(Notes.CONTENT_NOTE_URI, SqlNote.PROJECTION_NOTE, "(_id=?)",
+                    new String[] {
+                        String.valueOf(Notes.ID_CALL_RECORD_FOLDER)
+                    }, null);
+            if (c != null) {
+                if (c.moveToNext()) {
+                    gid = c.getString(SqlNote.GTASK_ID_COLUMN);
+                    node = mGTaskHashMap.get(gid);
+                    if (node != null) {
+                        mGTaskHashMap.remove(gid);
+                        mGidToNid.put(gid, (long) Notes.ID_CALL_RECORD_FOLDER);
+                        mNidToGid.put((long) Notes.ID_CALL_RECORD_FOLDER, gid);
+                        // for system folder, only update remote name if
+                        // necessary
+                        if (!node.getName().equals(
+                                GTaskStringUtils.MIUI_FOLDER_PREFFIX
+                                        + GTaskStringUtils.FOLDER_CALL_NOTE))
+                            doContentSync(Node.SYNC_ACTION_UPDATE_REMOTE, node, c);
+                    } else {
+                        doContentSync(Node.SYNC_ACTION_ADD_REMOTE, node, c);
+                    }
+                }
+            } else {
+                Log.w(TAG, "failed to query call note folder");
+            }
+        } finally {
+            if (c != null) {
+                c.close();
+                c = null;
+            }
+        }
+
+        // for local existing folders
+        try {
+            c = mContentResolver.query(Notes.CONTENT_NOTE_URI, SqlNote.PROJECTION_NOTE,
+                    "(type=? AND parent_id<>?)", new String[] {
+                            String.valueOf(Notes.TYPE_FOLDER), String.valueOf(Notes.ID_TRASH_FOLER)
+                    }, NoteColumns.TYPE + " DESC");
+            if (c != null) {
+                while (c.moveToNext()) {
+                    gid = c.getString(SqlNote.GTASK_ID_COLUMN);
+                    node = mGTaskHashMap.get(gid);
+                    if (node != null) {
+                        mGTaskHashMap.remove(gid);
+                        mGidToNid.put(gid, c.getLong(SqlNote.ID_COLUMN));
+                        mNidToGid.put(c.getLong(SqlNote.ID_COLUMN), gid);
+                        syncType = node.getSyncAction(c);
+                    } else {
+                        if (c.getString(SqlNote.GTASK_ID_COLUMN).trim().length() == 0) {
+                            // local add
+                            syncType = Node.SYNC_ACTION_ADD_REMOTE;
+                        } else {
+                            // remote delete
+                            syncType = Node.SYNC_ACTION_DEL_LOCAL;
+                        }
+                    }
+                    doContentSync(syncType, node, c);
+                }
+            } else {
+                Log.w(TAG, "failed to query existing folder");
+            }
+        } finally {
+            if (c != null) {
+                c.close();
+                c = null;
+            }
+        }
+
+        // for remote add folders
+        Iterator<Map.Entry<String, TaskList>> iter = mGTaskListHashMap.entrySet().iterator();
+        while (iter.hasNext()) {
+            Map.Entry<String, TaskList> entry = iter.next();
+            gid = entry.getKey();
+            node = entry.getValue();
+            if (mGTaskHashMap.containsKey(gid)) {
+                mGTaskHashMap.remove(gid);
+                doContentSync(Node.SYNC_ACTION_ADD_LOCAL, node, null);
+            }
+        }
+
+        if (!mCancelled)
+            GTaskClient.getInstance().commitUpdate();
+    }
+
+    private void doContentSync(int syncType, Node node, Cursor c) throws NetworkFailureException {
+        if (mCancelled) {
+            return;
+        }
+
+        MetaData meta;
+        switch (syncType) {
+            case Node.SYNC_ACTION_ADD_LOCAL:
+                addLocalNode(node);
+                break;
+            case Node.SYNC_ACTION_ADD_REMOTE:
+                addRemoteNode(node, c);
+                break;
+            case Node.SYNC_ACTION_DEL_LOCAL:
+                meta = mMetaHashMap.get(c.getString(SqlNote.GTASK_ID_COLUMN));
+                if (meta != null) {
+                    GTaskClient.getInstance().deleteNode(meta);
+                }
+                mLocalDeleteIdMap.add(c.getLong(SqlNote.ID_COLUMN));
+                break;
+            case Node.SYNC_ACTION_DEL_REMOTE:
+                meta = mMetaHashMap.get(node.getGid());
+                if (meta != null) {
+                    GTaskClient.getInstance().deleteNode(meta);
+                }
+                GTaskClient.getInstance().deleteNode(node);
+                break;
+            case Node.SYNC_ACTION_UPDATE_LOCAL:
+                updateLocalNode(node, c);
+                break;
+            case Node.SYNC_ACTION_UPDATE_REMOTE:
+                updateRemoteNode(node, c);
+                break;
+            case Node.SYNC_ACTION_UPDATE_CONFLICT:
+                // merging both modifications maybe a good idea
+                // right now just use local update simply
+                updateRemoteNode(node, c);
+                break;
+            case Node.SYNC_ACTION_NONE:
+                break;
+            case Node.SYNC_ACTION_ERROR:
+            default:
+                throw new ActionFailureException("unkown sync action type");
+        }
+    }
+
+    private void addLocalNode(Node node) throws NetworkFailureException {
+        if (mCancelled) {
+            return;
+        }
+
+        SqlNote sqlNote;
+        if (node instanceof TaskList) {
+            if (node.getName().equals(
+                    GTaskStringUtils.MIUI_FOLDER_PREFFIX + GTaskStringUtils.FOLDER_DEFAULT)) {
+                sqlNote = new SqlNote(mContext, Notes.ID_ROOT_FOLDER);
+            } else if (node.getName().equals(
+                    GTaskStringUtils.MIUI_FOLDER_PREFFIX + GTaskStringUtils.FOLDER_CALL_NOTE)) {
+                sqlNote = new SqlNote(mContext, Notes.ID_CALL_RECORD_FOLDER);
+            } else {
+                sqlNote = new SqlNote(mContext);
+                sqlNote.setContent(node.getLocalJSONFromContent());
+                sqlNote.setParentId(Notes.ID_ROOT_FOLDER);
+            }
+        } else {
+            sqlNote = new SqlNote(mContext);
+            JSONObject js = node.getLocalJSONFromContent();
+            try {
+                if (js.has(GTaskStringUtils.META_HEAD_NOTE)) {
+                    JSONObject note = js.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+                    if (note.has(NoteColumns.ID)) {
+                        long id = note.getLong(NoteColumns.ID);
+                        if (DataUtils.existInNoteDatabase(mContentResolver, id)) {
+                            // the id is not available, have to create a new one
+                            note.remove(NoteColumns.ID);
+                        }
+                    }
+                }
+
+                if (js.has(GTaskStringUtils.META_HEAD_DATA)) {
+                    JSONArray dataArray = js.getJSONArray(GTaskStringUtils.META_HEAD_DATA);
+                    for (int i = 0; i < dataArray.length(); i++) {
+                        JSONObject data = dataArray.getJSONObject(i);
+                        if (data.has(DataColumns.ID)) {
+                            long dataId = data.getLong(DataColumns.ID);
+                            if (DataUtils.existInDataDatabase(mContentResolver, dataId)) {
+                                // the data id is not available, have to create
+                                // a new one
+                                data.remove(DataColumns.ID);
+                            }
+                        }
+                    }
+
+                }
+            } catch (JSONException e) {
+                Log.w(TAG, e.toString());
+                e.printStackTrace();
+            }
+            sqlNote.setContent(js);
+
+            Long parentId = mGidToNid.get(((Task) node).getParent().getGid());
+            if (parentId == null) {
+                Log.e(TAG, "cannot find task's parent id locally");
+                throw new ActionFailureException("cannot add local node");
+            }
+            sqlNote.setParentId(parentId.longValue());
+        }
+
+        // create the local node
+        sqlNote.setGtaskId(node.getGid());
+        sqlNote.commit(false);
+
+        // update gid-nid mapping
+        mGidToNid.put(node.getGid(), sqlNote.getId());
+        mNidToGid.put(sqlNote.getId(), node.getGid());
+
+        // update meta
+        updateRemoteMeta(node.getGid(), sqlNote);
+    }
+
+    private void updateLocalNode(Node node, Cursor c) throws NetworkFailureException {
+        if (mCancelled) {
+            return;
+        }
+
+        SqlNote sqlNote;
+        // update the note locally
+        sqlNote = new SqlNote(mContext, c);
+        sqlNote.setContent(node.getLocalJSONFromContent());
+
+        Long parentId = (node instanceof Task) ? mGidToNid.get(((Task) node).getParent().getGid())
+                : new Long(Notes.ID_ROOT_FOLDER);
+        if (parentId == null) {
+            Log.e(TAG, "cannot find task's parent id locally");
+            throw new ActionFailureException("cannot update local node");
+        }
+        sqlNote.setParentId(parentId.longValue());
+        sqlNote.commit(true);
+
+        // update meta info
+        updateRemoteMeta(node.getGid(), sqlNote);
+    }
+
+    private void addRemoteNode(Node node, Cursor c) throws NetworkFailureException {
+        if (mCancelled) {
+            return;
+        }
+
+        SqlNote sqlNote = new SqlNote(mContext, c);
+        Node n;
+
+        // update remotely
+        if (sqlNote.isNoteType()) {
+            Task task = new Task();
+            task.setContentByLocalJSON(sqlNote.getContent());
+
+            String parentGid = mNidToGid.get(sqlNote.getParentId());
+            if (parentGid == null) {
+                Log.e(TAG, "cannot find task's parent tasklist");
+                throw new ActionFailureException("cannot add remote task");
+            }
+            mGTaskListHashMap.get(parentGid).addChildTask(task);
+
+            GTaskClient.getInstance().createTask(task);
+            n = (Node) task;
+
+            // add meta
+            updateRemoteMeta(task.getGid(), sqlNote);
+        } else {
+            TaskList tasklist = null;
+
+            // we need to skip folder if it has already existed
+            String folderName = GTaskStringUtils.MIUI_FOLDER_PREFFIX;
+            if (sqlNote.getId() == Notes.ID_ROOT_FOLDER)
+                folderName += GTaskStringUtils.FOLDER_DEFAULT;
+            else if (sqlNote.getId() == Notes.ID_CALL_RECORD_FOLDER)
+                folderName += GTaskStringUtils.FOLDER_CALL_NOTE;
+            else
+                folderName += sqlNote.getSnippet();
+
+            Iterator<Map.Entry<String, TaskList>> iter = mGTaskListHashMap.entrySet().iterator();
+            while (iter.hasNext()) {
+                Map.Entry<String, TaskList> entry = iter.next();
+                String gid = entry.getKey();
+                TaskList list = entry.getValue();
+
+                if (list.getName().equals(folderName)) {
+                    tasklist = list;
+                    if (mGTaskHashMap.containsKey(gid)) {
+                        mGTaskHashMap.remove(gid);
+                    }
+                    break;
+                }
+            }
+
+            // no match we can add now
+            if (tasklist == null) {
+                tasklist = new TaskList();
+                tasklist.setContentByLocalJSON(sqlNote.getContent());
+                GTaskClient.getInstance().createTaskList(tasklist);
+                mGTaskListHashMap.put(tasklist.getGid(), tasklist);
+            }
+            n = (Node) tasklist;
+        }
+
+        // update local note
+        sqlNote.setGtaskId(n.getGid());
+        sqlNote.commit(false);
+        sqlNote.resetLocalModified();
+        sqlNote.commit(true);
+
+        // gid-id mapping
+        mGidToNid.put(n.getGid(), sqlNote.getId());
+        mNidToGid.put(sqlNote.getId(), n.getGid());
+    }
+
+    private void updateRemoteNode(Node node, Cursor c) throws NetworkFailureException {
+        if (mCancelled) {
+            return;
+        }
+
+        SqlNote sqlNote = new SqlNote(mContext, c);
+
+        // update remotely
+        node.setContentByLocalJSON(sqlNote.getContent());
+        GTaskClient.getInstance().addUpdateNode(node);
+
+        // update meta
+        updateRemoteMeta(node.getGid(), sqlNote);
+
+        // move task if necessary
+        if (sqlNote.isNoteType()) {
+            Task task = (Task) node;
+            TaskList preParentList = task.getParent();
+
+            String curParentGid = mNidToGid.get(sqlNote.getParentId());
+            if (curParentGid == null) {
+                Log.e(TAG, "cannot find task's parent tasklist");
+                throw new ActionFailureException("cannot update remote task");
+            }
+            TaskList curParentList = mGTaskListHashMap.get(curParentGid);
+
+            if (preParentList != curParentList) {
+                preParentList.removeChildTask(task);
+                curParentList.addChildTask(task);
+                GTaskClient.getInstance().moveTask(task, preParentList, curParentList);
+            }
+        }
+
+        // clear local modified flag
+        sqlNote.resetLocalModified();
+        sqlNote.commit(true);
+    }
+
+    private void updateRemoteMeta(String gid, SqlNote sqlNote) throws NetworkFailureException {
+        if (sqlNote != null && sqlNote.isNoteType()) {
+            MetaData metaData = mMetaHashMap.get(gid);
+            if (metaData != null) {
+                metaData.setMeta(gid, sqlNote.getContent());
+                GTaskClient.getInstance().addUpdateNode(metaData);
+            } else {
+                metaData = new MetaData();
+                metaData.setMeta(gid, sqlNote.getContent());
+                mMetaList.addChildTask(metaData);
+                mMetaHashMap.put(gid, metaData);
+                GTaskClient.getInstance().createTask(metaData);
+            }
+        }
+    }
+
+    private void refreshLocalSyncId() throws NetworkFailureException {
+        if (mCancelled) {
+            return;
+        }
+
+        // get the latest gtask list
+        mGTaskHashMap.clear();
+        mGTaskListHashMap.clear();
+        mMetaHashMap.clear();
+        initGTaskList();
+
+        Cursor c = null;
+        try {
+            c = mContentResolver.query(Notes.CONTENT_NOTE_URI, SqlNote.PROJECTION_NOTE,
+                    "(type<>? AND parent_id<>?)", new String[] {
+                            String.valueOf(Notes.TYPE_SYSTEM), String.valueOf(Notes.ID_TRASH_FOLER)
+                    }, NoteColumns.TYPE + " DESC");
+            if (c != null) {
+                while (c.moveToNext()) {
+                    String gid = c.getString(SqlNote.GTASK_ID_COLUMN);
+                    Node node = mGTaskHashMap.get(gid);
+                    if (node != null) {
+                        mGTaskHashMap.remove(gid);
+                        ContentValues values = new ContentValues();
+                        values.put(NoteColumns.SYNC_ID, node.getLastModified());
+                        mContentResolver.update(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI,
+                                c.getLong(SqlNote.ID_COLUMN)), values, null, null);
+                    } else {
+                        Log.e(TAG, "something is missed");
+                        throw new ActionFailureException(
+                                "some local items don't have gid after sync");
+                    }
+                }
+            } else {
+                Log.w(TAG, "failed to query local note to refresh sync id");
+            }
+        } finally {
+            if (c != null) {
+                c.close();
+                c = null;
+            }
+        }
+    }
+
+    public String getSyncAccount() {
+        return GTaskClient.getInstance().getSyncAccount().name;
+    }
+
+    public void cancelSync() {
+        mCancelled = true;
+    }
+}

java/net/micode/notes/gtask/remote/GTaskSyncService.java

@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.remote;
+
+import android.app.Activity;
+import android.app.Service;
+import android.content.Context;
+import android.content.Intent;
+import android.os.Bundle;
+import android.os.IBinder;
+
+public class GTaskSyncService extends Service {
+    public final static String ACTION_STRING_NAME = "sync_action_type";
+
+    public final static int ACTION_START_SYNC = 0;
+
+    public final static int ACTION_CANCEL_SYNC = 1;
+
+    public final static int ACTION_INVALID = 2;
+
+    public final static String GTASK_SERVICE_BROADCAST_NAME = "net.micode.notes.gtask.remote.gtask_sync_service";
+
+    public final static String GTASK_SERVICE_BROADCAST_IS_SYNCING = "isSyncing";
+
+    public final static String GTASK_SERVICE_BROADCAST_PROGRESS_MSG = "progressMsg";
+
+    private static GTaskASyncTask mSyncTask = null;
+
+    private static String mSyncProgress = "";
+
+    private void startSync() {
+        if (mSyncTask == null) {
+            mSyncTask = new GTaskASyncTask(this, new GTaskASyncTask.OnCompleteListener() {
+                public void onComplete() {
+                    mSyncTask = null;
+                    sendBroadcast("");
+                    stopSelf();
+                }
+            });
+            sendBroadcast("");
+            mSyncTask.execute();
+        }
+    }
+
+    private void cancelSync() {
+        if (mSyncTask != null) {
+            mSyncTask.cancelSync();
+        }
+    }
+
+    @Override
+    public void onCreate() {
+        mSyncTask = null;
+    }
+
+    @Override
+    public int onStartCommand(Intent intent, int flags, int startId) {
+        Bundle bundle = intent.getExtras();
+        if (bundle != null && bundle.containsKey(ACTION_STRING_NAME)) {
+            switch (bundle.getInt(ACTION_STRING_NAME, ACTION_INVALID)) {
+                case ACTION_START_SYNC:
+                    startSync();
+                    break;
+                case ACTION_CANCEL_SYNC:
+                    cancelSync();
+                    break;
+                default:
+                    break;
+            }
+            return START_STICKY;
+        }
+        return super.onStartCommand(intent, flags, startId);
+    }
+
+    @Override
+    public void onLowMemory() {
+        if (mSyncTask != null) {
+            mSyncTask.cancelSync();
+        }
+    }
+
+    public IBinder onBind(Intent intent) {
+        return null;
+    }
+
+    public void sendBroadcast(String msg) {
+        mSyncProgress = msg;
+        Intent intent = new Intent(GTASK_SERVICE_BROADCAST_NAME);
+        intent.putExtra(GTASK_SERVICE_BROADCAST_IS_SYNCING, mSyncTask != null);
+        intent.putExtra(GTASK_SERVICE_BROADCAST_PROGRESS_MSG, msg);
+        sendBroadcast(intent);
+    }
+
+    public static void startSync(Activity activity) {
+        GTaskManager.getInstance().setActivityContext(activity);
+        Intent intent = new Intent(activity, GTaskSyncService.class);
+        intent.putExtra(GTaskSyncService.ACTION_STRING_NAME, GTaskSyncService.ACTION_START_SYNC);
+        activity.startService(intent);
+    }
+
+    public static void cancelSync(Context context) {
+        Intent intent = new Intent(context, GTaskSyncService.class);
+        intent.putExtra(GTaskSyncService.ACTION_STRING_NAME, GTaskSyncService.ACTION_CANCEL_SYNC);
+        context.startService(intent);
+    }
+
+    public static boolean isSyncing() {
+        return mSyncTask != null;
+    }
+
+    public static String getProgressString() {
+        return mSyncProgress;
+    }
+}

java/net/micode/notes/model/Note.java

@@ -0,0 +1,308 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了Note类，其围绕笔记数据的创建、修改以及与内容提供器（Content Provider）交互进行同步等操作构建逻辑，是笔记数据管理的核心类之一。类中不仅包含了用于创建新笔记并获取其ID的方法，还定义了针对笔记不同类型数据（文本数据、通话数据等）的设置方法，同时通过判断笔记是否有本地修改来决定是否执行同步操作，将修改后的数据更新到对应的数据库中，内部的NoteData私有内部类则进一步细化了对笔记附属数据（文本、通话相关）的管理与操作逻辑，整体助力实现笔记数据在应用内准确、有效的维护与持久化存储。
+函数分析
+getNewNoteId方法
+所属类：Note
+功能：通过构建ContentValues对象设置新笔记的创建时间、修改时间、类型、本地修改标志以及所属文件夹ID等初始属性，然后利用ContentResolver将这些数据插入到笔记数据库（Notes.CONTENT_NOTE_URI）中，接着尝试从返回的Uri中解析出笔记ID，若解析出现异常或者获取到的ID为特定错误值（如-1）则进行相应错误处理，最终返回新创建笔记的ID，用于生成新笔记并获取其唯一标识符。
+Note类构造函数
+所属类：Note
+功能：初始化mNoteDiffValues（用于存储笔记主要属性变更值的ContentValues对象）和mNoteData（管理笔记附属数据的NoteData对象），为后续对笔记数据的操作准备好相关的数据容器。
+setNoteValue方法
+所属类：Note
+功能：将传入的键值对添加到mNoteDiffValues中，并同时设置本地修改标志以及更新修改时间，用于更新笔记的主要属性数据，标记其已被修改。
+setTextData方法
+所属类：Note
+功能：调用内部NoteData对象的setTextData方法，传入键值对，将文本相关的数据信息添加到对应的ContentValues对象中，同时更新笔记的修改相关状态，用于设置笔记的文本数据内容。
+setTextDataId方法
+所属类：Note
+功能：调用内部NoteData对象的setTextDataId方法，传入ID值，用于设置笔记的文本数据的ID，且会对传入ID进行合法性判断（大于0），不符合则抛出异常。
+getTextDataId方法
+所属类：Note
+功能：返回内部NoteData对象中记录的文本数据的ID，用于获取笔记关联的文本数据的标识符。
+setCallDataId方法
+所属类：Note
+功能：调用内部NoteData对象的setCallDataId方法，传入ID值，用于设置笔记的通话数据的ID，同样会对传入ID进行合法性判断（大于0），不符合则抛出异常。
+setCallData方法
+所属类：Note
+功能：调用内部NoteData对象的setCallData方法，传入键值对，将通话相关的数据信息添加到对应的ContentValues对象中，同时更新笔记的修改相关状态，用于设置笔记的通话数据内容。
+isLocalModified方法
+所属类：Note
+功能：通过判断mNoteDiffValues（笔记主要属性变更值）以及内部NoteData对象是否有数据变化（通过其isLocalModified方法判断），返回笔记整体是否有本地修改的布尔值，用于确定笔记数据是否发生了本地变更，进而决定是否需要执行同步等后续操作。
+syncNote方法
+所属类：Note
+功能：首先对传入的笔记ID进行合法性判断，若笔记无本地修改则直接返回true表示无需同步操作。若有本地修改，先尝试通过ContentResolver更新笔记的主要属性（利用mNoteDiffValues中的数据），更新失败会记录错误日志但继续后续流程，接着清空mNoteDiffValues，再判断笔记附属数据（通过内部NoteData对象判断）是否有修改且能否成功推送更新到内容提供器中，根据推送结果返回相应布尔值，以此实现将本地修改的笔记数据同步到对应数据库的功能。
+NoteData类相关函数
+构造函数：
+所属类：Note.NoteData（Note的内部类）
+功能：初始化用于存储文本数据和通话数据的ContentValues对象，以及文本数据ID和通话数据ID，为后续管理笔记附属数据准备好相关的数据结构和初始值。
+isLocalModified方法：
+所属类：Note.NoteData（Note的内部类）
+功能：通过判断文本数据和通话数据对应的ContentValues对象中是否有数据（即其size是否大于0），返回笔记附属数据是否有本地修改的布尔值，用于在外部判断笔记整体是否有变化时提供附属数据部分的修改情况判断依据。
+setTextDataId方法：
+所属类：Note.NoteData（Note的内部类）
+功能：对传入的文本数据ID进行合法性判断（要求大于0），符合则设置到对应的成员变量中，不符合则抛出异常，用于设置笔记的文本数据的ID，保证ID值的有效性。
+setCallDataId方法：
+所属类：Note.NoteData（Note的内部类）
+功能：与setTextDataId类似，对传入的通话数据ID进行合法性判断（大于0），符合则设置到对应的成员变量中，不符合则抛出异常，用于设置笔记的通话数据的ID，确保ID值合法合规。
+setCallData方法：
+所属类：Note.NoteData（Note的内部类）
+功能：将传入的通话数据相关键值对添加到通话数据对应的ContentValues对象中，同时更新外部笔记的修改相关状态，用于设置笔记的通话数据内容，并标记笔记已被修改。
+setTextData方法：
+所属类：Note.NoteData（Note的内部类）
+功能：将传入的文本数据相关键值对添加到文本数据对应的ContentValues对象中，同时更新外部笔记的修改相关状态，用于设置笔记的文本数据内容，并标记笔记已被修改。
+pushIntoContentResolver方法：
+所属类：Note.NoteData（Note的内部类）
+功能：先对传入的笔记ID进行合法性判断，接着根据文本数据和通话数据对应的ContentValues对象是否有数据，分情况进行操作。若有数据，设置笔记ID关联，若对应数据ID为0则插入新数据到数据库并获取新ID，否则构建更新操作添加到操作列表，最后若操作列表有元素，则通过ContentResolver批量执行操作，根据执行结果返回相应Uri或null，以此实现将笔记附属数据更新到内容提供器对应的数据库中的功能。
+ */
+
+package net.micode.notes.model;
+import android.content.ContentProviderOperation;
+import android.content.ContentProviderResult;
+import android.content.ContentUris;
+import android.content.ContentValues;
+import android.content.Context;
+import android.content.OperationApplicationException;
+import android.net.Uri;
+import android.os.RemoteException;
+import android.util.Log;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.CallNote;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.data.Notes.TextNote;
+
+import java.util.ArrayList;
+
+
+public class Note {
+    private ContentValues mNoteDiffValues;
+    private NoteData mNoteData;
+    private static final String TAG = "Note";
+    /**
+     * Create a new note id for adding a new note to databases
+     */
+    public static synchronized long getNewNoteId(Context context, long folderId) {
+        // Create a new note in the database
+        ContentValues values = new ContentValues();
+        long createdTime = System.currentTimeMillis();
+        values.put(NoteColumns.CREATED_DATE, createdTime);
+        values.put(NoteColumns.MODIFIED_DATE, createdTime);
+        values.put(NoteColumns.TYPE, Notes.TYPE_NOTE);
+        values.put(NoteColumns.LOCAL_MODIFIED, 1);
+        values.put(NoteColumns.PARENT_ID, folderId);
+        Uri uri = context.getContentResolver().insert(Notes.CONTENT_NOTE_URI, values);
+
+        long noteId = 0;
+        try {
+            noteId = Long.valueOf(uri.getPathSegments().get(1));
+        } catch (NumberFormatException e) {
+            Log.e(TAG, "Get note id error :" + e.toString());
+            noteId = 0;
+        }
+        if (noteId == -1) {
+            throw new IllegalStateException("Wrong note id:" + noteId);
+        }
+        return noteId;
+    }
+
+    public Note() {
+        mNoteDiffValues = new ContentValues();
+        mNoteData = new NoteData();
+    }
+
+    public void setNoteValue(String key, String value) {
+        mNoteDiffValues.put(key, value);
+        mNoteDiffValues.put(NoteColumns.LOCAL_MODIFIED, 1);
+        mNoteDiffValues.put(NoteColumns.MODIFIED_DATE, System.currentTimeMillis());
+    }
+
+    public void setTextData(String key, String value) {
+        mNoteData.setTextData(key, value);
+    }
+
+    public void setTextDataId(long id) {
+        mNoteData.setTextDataId(id);
+    }
+
+    public long getTextDataId() {
+        return mNoteData.mTextDataId;
+    }
+
+    public void setCallDataId(long id) {
+        mNoteData.setCallDataId(id);
+    }
+
+    public void setCallData(String key, String value) {
+        mNoteData.setCallData(key, value);
+    }
+
+    public boolean isLocalModified() {
+        return mNoteDiffValues.size() > 0 || mNoteData.isLocalModified();
+    }
+
+    public boolean syncNote(Context context, long noteId) {
+        if (noteId <= 0) {
+            throw new IllegalArgumentException("Wrong note id:" + noteId);
+        }
+
+        if (!isLocalModified()) {
+            return true;
+        }
+
+        /**
+         * In theory, once data changed, the note should be updated on {@link NoteColumns#LOCAL_MODIFIED} and
+         * {@link NoteColumns#MODIFIED_DATE}. For data safety, though update note fails, we also update the
+         * note data info
+         */
+        if (context.getContentResolver().update(
+                ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId), mNoteDiffValues, null,
+                null) == 0) {
+            Log.e(TAG, "Update note error, should not happen");
+            // Do not return, fall through
+        }
+        mNoteDiffValues.clear();
+
+        if (mNoteData.isLocalModified()
+                && (mNoteData.pushIntoContentResolver(context, noteId) == null)) {
+            return false;
+        }
+
+        return true;
+    }
+
+    private class NoteData {
+        private long mTextDataId;
+
+        private ContentValues mTextDataValues;
+
+        private long mCallDataId;
+
+        private ContentValues mCallDataValues;
+
+        private static final String TAG = "NoteData";
+
+        public NoteData() {
+            mTextDataValues = new ContentValues();
+            mCallDataValues = new ContentValues();
+            mTextDataId = 0;
+            mCallDataId = 0;
+        }
+
+        boolean isLocalModified() {
+            return mTextDataValues.size() > 0 || mCallDataValues.size() > 0;
+        }
+
+        void setTextDataId(long id) {
+            if(id <= 0) {
+                throw new IllegalArgumentException("Text data id should larger than 0");
+            }
+            mTextDataId = id;
+        }
+
+        void setCallDataId(long id) {
+            if (id <= 0) {
+                throw new IllegalArgumentException("Call data id should larger than 0");
+            }
+            mCallDataId = id;
+        }
+
+        void setCallData(String key, String value) {
+            mCallDataValues.put(key, value);
+            mNoteDiffValues.put(NoteColumns.LOCAL_MODIFIED, 1);
+            mNoteDiffValues.put(NoteColumns.MODIFIED_DATE, System.currentTimeMillis());
+        }
+
+        void setTextData(String key, String value) {
+            mTextDataValues.put(key, value);
+            mNoteDiffValues.put(NoteColumns.LOCAL_MODIFIED, 1);
+            mNoteDiffValues.put(NoteColumns.MODIFIED_DATE, System.currentTimeMillis());
+        }
+
+        Uri pushIntoContentResolver(Context context, long noteId) {
+            /**
+             * Check for safety
+             */
+            if (noteId <= 0) {
+                throw new IllegalArgumentException("Wrong note id:" + noteId);
+            }
+
+            ArrayList<ContentProviderOperation> operationList = new ArrayList<ContentProviderOperation>();
+            ContentProviderOperation.Builder builder = null;
+
+            if(mTextDataValues.size() > 0) {
+                mTextDataValues.put(DataColumns.NOTE_ID, noteId);
+                if (mTextDataId == 0) {
+                    mTextDataValues.put(DataColumns.MIME_TYPE, TextNote.CONTENT_ITEM_TYPE);
+                    Uri uri = context.getContentResolver().insert(Notes.CONTENT_DATA_URI,
+                            mTextDataValues);
+                    try {
+                        setTextDataId(Long.valueOf(uri.getPathSegments().get(1)));
+                    } catch (NumberFormatException e) {
+                        Log.e(TAG, "Insert new text data fail with noteId" + noteId);
+                        mTextDataValues.clear();
+                        return null;
+                    }
+                } else {
+                    builder = ContentProviderOperation.newUpdate(ContentUris.withAppendedId(
+                            Notes.CONTENT_DATA_URI, mTextDataId));
+                    builder.withValues(mTextDataValues);
+                    operationList.add(builder.build());
+                }
+                mTextDataValues.clear();
+            }
+
+            if(mCallDataValues.size() > 0) {
+                mCallDataValues.put(DataColumns.NOTE_ID, noteId);
+                if (mCallDataId == 0) {
+                    mCallDataValues.put(DataColumns.MIME_TYPE, CallNote.CONTENT_ITEM_TYPE);
+                    Uri uri = context.getContentResolver().insert(Notes.CONTENT_DATA_URI,
+                            mCallDataValues);
+                    try {
+                        setCallDataId(Long.valueOf(uri.getPathSegments().get(1)));
+                    } catch (NumberFormatException e) {
+                        Log.e(TAG, "Insert new call data fail with noteId" + noteId);
+                        mCallDataValues.clear();
+                        return null;
+                    }
+                } else {
+                    builder = ContentProviderOperation.newUpdate(ContentUris.withAppendedId(
+                            Notes.CONTENT_DATA_URI, mCallDataId));
+                    builder.withValues(mCallDataValues);
+                    operationList.add(builder.build());
+                }
+                mCallDataValues.clear();
+            }
+
+            if (operationList.size() > 0) {
+                try {
+                    ContentProviderResult[] results = context.getContentResolver().applyBatch(
+                            Notes.AUTHORITY, operationList);
+                    return (results == null || results.length == 0 || results[0] == null) ? null
+                            : ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId);
+                } catch (RemoteException e) {
+                    Log.e(TAG, String.format("%s: %s", e.toString(), e.getMessage()));
+                    return null;
+                } catch (OperationApplicationException e) {
+                    Log.e(TAG, String.format("%s: %s", e.toString(), e.getMessage()));
+                    return null;
+                }
+            }
+            return null;
+        }
+    }
+}

java/net/micode/notes/model/WorkingNote.java

@@ -0,0 +1,442 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了WorkingNote类，它是对笔记相关操作及状态管理的核心类，整合了笔记从创建、加载、保存到各种属性设置及状态变更等多方面的功能逻辑。类中通过不同的构造函数来区分新建笔记和加载已有笔记的情况，在加载过程中会从数据库获取笔记及附属数据的相关信息进行初始化。同时提供了诸多方法用于设置笔记的各类属性（如背景颜色、提醒日期、部件相关属性等）以及判断笔记是否值得保存、是否存在于数据库等，并且定义了一个接口用于监听笔记相关设置状态变化，整体围绕着笔记在应用内的完整生命周期管理及与用户交互过程中的状态响应来构建功能。
+函数分析
+构造函数相关
+WorkingNote(Context context, long folderId)构造函数：
+所属类：WorkingNote
+功能：用于创建新笔记的初始化，接收应用上下文和所属文件夹ID，设置提醒日期、修改日期、初始化笔记对象、笔记ID、删除状态、模式等属性，为新建笔记准备基础数据。
+WorkingNote(Context context, long noteId, long folderId)构造函数：
+所属类：WorkingNote
+功能：针对加载已有笔记的情况，接收应用上下文、笔记ID和所属文件夹ID，初始化相关属性后调用loadNote方法从数据库加载笔记具体信息，用于还原已有笔记的各项数据状态。
+loadNote方法
+所属类：WorkingNote
+功能：通过ContentResolver根据笔记ID查询笔记的部分关键属性（如父ID、背景颜色ID等），若游标不为null且能移动到第一条记录，则获取对应属性值进行赋值，游标遍历完后关闭游标，若游标为null则抛出异常，接着调用loadNoteData方法加载笔记附属数据，整体实现从数据库加载笔记基本信息的功能。
+loadNoteData方法
+所属类：WorkingNote
+功能：利用ContentResolver依据笔记ID查询笔记附属数据，若游标不为null且能移动到第一条记录，则遍历游标，根据数据的MIME_TYPE判断类型（如普通笔记、通话记录等），分别进行对应的数据处理（如设置文本数据ID、通话数据ID等），游标遍历完后关闭游标，若游标为null则抛出异常，用于加载笔记关联的具体数据内容。
+createEmptyNote方法
+所属类：WorkingNote
+功能：创建一个新的空笔记对象，传入应用上下文、所属文件夹ID、部件ID、部件类型和默认背景颜色ID等参数，先实例化WorkingNote对象，再设置其背景颜色ID、部件ID和部件类型等属性，最后返回创建好的空笔记对象，用于便捷地创建具有初始属性配置的新笔记。
+load方法
+所属类：WorkingNote
+功能：接收应用上下文和笔记ID，通过调用对应构造函数创建并返回一个用于加载已有笔记的WorkingNote对象，方便从外部根据ID获取对应的笔记实例进行后续操作。
+saveNote方法
+所属类：WorkingNote
+功能：先判断笔记是否值得保存（通过isWorthSaving方法判断），若值得保存且笔记不存在于数据库中，则尝试创建新笔记并获取其ID，若创建失败则记录日志并返回false；接着调用笔记对象的syncNote方法将本地修改同步到数据库；若笔记存在部件且相关监听不为null，则触发部件变更监听回调，最后根据操作情况返回对应的布尔值，用于实现将笔记数据保存到数据库以及响应部件相关变更的功能。
+existInDatabase方法
+所属类：WorkingNote
+功能：通过判断笔记ID是否大于0，返回笔记是否存在于数据库中的布尔值，用于简单确认笔记在数据库中的存在情况。
+isWorthSaving方法
+所属类：WorkingNote
+功能：根据笔记的删除状态、在数据库中的存在情况以及内容是否为空、笔记是否有本地修改等条件综合判断笔记是否值得保存，返回对应的布尔值，为saveNote等方法决定是否执行保存操作提供依据。
+setOnSettingStatusChangedListener方法
+所属类：WorkingNote
+功能：设置笔记设置状态变更的监听器对象，用于后续在笔记相关属性（如背景颜色、提醒等）变更时能触发对应的回调方法，实现外部对笔记状态变化的监听与响应。
+setAlertDate方法
+所属类：WorkingNote
+功能：若传入的提醒日期与当前记录的提醒日期不同，则更新提醒日期，并通过笔记对象设置对应属性值，若监听器不为null，则触发提醒日期变更的监听回调，用于设置笔记的提醒日期并通知外部监听者。
+markDeleted方法
+所属类：WorkingNote
+功能：更新笔记的删除标记状态，若笔记存在部件且相关监听不为null，则触发部件变更的监听回调，用于标记笔记是否已删除并响应部件相关变化。
+setBgColorId方法
+所属类：WorkingNote
+功能：若传入的背景颜色ID与当前记录的不同，则更新背景颜色ID，触发背景颜色变更的监听回调，并通过笔记对象设置对应属性值，用于设置笔记的背景颜色ID并通知外部监听者。
+setCheckListMode方法
+所属类：WorkingNote
+功能：若传入的清单模式与当前记录的不同，则更新清单模式，触发清单模式变更的监听回调，并通过笔记对象设置对应文本数据，用于设置笔记的清单模式并通知外部监听者。
+setWidgetType方法
+所属类：WorkingNote
+功能：若传入的部件类型与当前记录的不同，则更新部件类型，并通过笔记对象设置对应属性值，用于设置笔记的部件类型。
+setWidgetId方法
+所属类：WorkingNote
+功能：若传入的部件ID与当前记录的不同，则更新部件ID，并通过笔记对象设置对应属性值，用于设置笔记的部件ID。
+setWorkingText方法
+所属类：WorkingNote
+功能：若传入的文本内容与当前记录的不同，则更新文本内容，并通过笔记对象设置对应文本数据，用于设置笔记的工作文本内容。
+convertToCallNote方法
+所属类：WorkingNote
+功能：设置笔记的通话相关数据（如通话日期、电话号码）以及所属文件夹ID为通话记录文件夹ID，用于将普通笔记转换为通话记录类型的笔记。
+hasClockAlert方法
+所属类：WorkingNote
+功能：通过判断提醒日期是否大于0，返回笔记是否设置了时钟提醒的布尔值，用于知晓笔记是否有提醒功能开启。
+getContent方法
+所属类：WorkingNote
+功能：返回笔记的文本内容，用于获取笔记中记录的具体内容信息。
+getAlertDate方法
+所属类：WorkingNote
+功能：返回笔记设置的提醒日期，用于获取笔记的提醒相关信息。
+getModifiedDate方法
+所属类：WorkingNote
+功能：返回笔记的最后修改日期，用于了解笔记的修改时间情况。
+getBgColorResId方法
+所属类：WorkingNote
+功能：通过调用NoteBgResources的对应方法，根据背景颜色ID获取笔记背景资源的ID，用于获取笔记对应的背景资源标识符。
+getBgColorId方法
+ */
+
+package net.micode.notes.model;
+
+import android.appwidget.AppWidgetManager;
+import android.content.ContentUris;
+import android.content.Context;
+import android.database.Cursor;
+import android.text.TextUtils;
+import android.util.Log;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.CallNote;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.DataConstants;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.data.Notes.TextNote;
+import net.micode.notes.tool.ResourceParser.NoteBgResources;
+
+
+public class WorkingNote {
+    // Note for the working note
+    private Note mNote;
+    // Note Id
+    private long mNoteId;
+    // Note content
+    private String mContent;
+    // Note mode
+    private int mMode;
+
+    private long mAlertDate;
+
+    private long mModifiedDate;
+
+    private int mBgColorId;
+
+    private int mWidgetId;
+
+    private int mWidgetType;
+
+    private long mFolderId;
+
+    private Context mContext;
+
+    private static final String TAG = "WorkingNote";
+
+    private boolean mIsDeleted;
+
+    private NoteSettingChangedListener mNoteSettingStatusListener;
+
+    public static final String[] DATA_PROJECTION = new String[] {
+            DataColumns.ID,
+            DataColumns.CONTENT,
+            DataColumns.MIME_TYPE,
+            DataColumns.DATA1,
+            DataColumns.DATA2,
+            DataColumns.DATA3,
+            DataColumns.DATA4,
+    };
+
+    public static final String[] NOTE_PROJECTION = new String[] {
+            NoteColumns.PARENT_ID,
+            NoteColumns.ALERTED_DATE,
+            NoteColumns.BG_COLOR_ID,
+            NoteColumns.WIDGET_ID,
+            NoteColumns.WIDGET_TYPE,
+            NoteColumns.MODIFIED_DATE
+    };
+
+    private static final int DATA_ID_COLUMN = 0;
+
+    private static final int DATA_CONTENT_COLUMN = 1;
+
+    private static final int DATA_MIME_TYPE_COLUMN = 2;
+
+    private static final int DATA_MODE_COLUMN = 3;
+
+    private static final int NOTE_PARENT_ID_COLUMN = 0;
+
+    private static final int NOTE_ALERTED_DATE_COLUMN = 1;
+
+    private static final int NOTE_BG_COLOR_ID_COLUMN = 2;
+
+    private static final int NOTE_WIDGET_ID_COLUMN = 3;
+
+    private static final int NOTE_WIDGET_TYPE_COLUMN = 4;
+
+    private static final int NOTE_MODIFIED_DATE_COLUMN = 5;
+
+    // New note construct
+    private WorkingNote(Context context, long folderId) {
+        mContext = context;
+        mAlertDate = 0;
+        mModifiedDate = System.currentTimeMillis();
+        mFolderId = folderId;
+        mNote = new Note();
+        mNoteId = 0;
+        mIsDeleted = false;
+        mMode = 0;
+        mWidgetType = Notes.TYPE_WIDGET_INVALIDE;
+    }
+
+    // Existing note construct
+    private WorkingNote(Context context, long noteId, long folderId) {
+        mContext = context;
+        mNoteId = noteId;
+        mFolderId = folderId;
+        mIsDeleted = false;
+        mNote = new Note();
+        loadNote();
+    }
+
+    private void loadNote() {
+        Cursor cursor = mContext.getContentResolver().query(
+                ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, mNoteId), NOTE_PROJECTION, null,
+                null, null);
+
+        if (cursor != null) {
+            if (cursor.moveToFirst()) {
+                mFolderId = cursor.getLong(NOTE_PARENT_ID_COLUMN);
+                mBgColorId = cursor.getInt(NOTE_BG_COLOR_ID_COLUMN);
+                mWidgetId = cursor.getInt(NOTE_WIDGET_ID_COLUMN);
+                mWidgetType = cursor.getInt(NOTE_WIDGET_TYPE_COLUMN);
+                mAlertDate = cursor.getLong(NOTE_ALERTED_DATE_COLUMN);
+                mModifiedDate = cursor.getLong(NOTE_MODIFIED_DATE_COLUMN);
+            }
+            cursor.close();
+        } else {
+            Log.e(TAG, "No note with id:" + mNoteId);
+            throw new IllegalArgumentException("Unable to find note with id " + mNoteId);
+        }
+        loadNoteData();
+    }
+
+    private void loadNoteData() {
+        Cursor cursor = mContext.getContentResolver().query(Notes.CONTENT_DATA_URI, DATA_PROJECTION,
+                DataColumns.NOTE_ID + "=?", new String[] {
+                    String.valueOf(mNoteId)
+                }, null);
+
+        if (cursor != null) {
+            if (cursor.moveToFirst()) {
+                do {
+                    String type = cursor.getString(DATA_MIME_TYPE_COLUMN);
+                    if (DataConstants.NOTE.equals(type)) {
+                        mContent = cursor.getString(DATA_CONTENT_COLUMN);
+                        mMode = cursor.getInt(DATA_MODE_COLUMN);
+                        mNote.setTextDataId(cursor.getLong(DATA_ID_COLUMN));
+                    } else if (DataConstants.CALL_NOTE.equals(type)) {
+                        mNote.setCallDataId(cursor.getLong(DATA_ID_COLUMN));
+                    } else {
+                        Log.d(TAG, "Wrong note type with type:" + type);
+                    }
+                } while (cursor.moveToNext());
+            }
+            cursor.close();
+        } else {
+            Log.e(TAG, "No data with id:" + mNoteId);
+            throw new IllegalArgumentException("Unable to find note's data with id " + mNoteId);
+        }
+    }
+
+    public static WorkingNote createEmptyNote(Context context, long folderId, int widgetId,
+            int widgetType, int defaultBgColorId) {
+        WorkingNote note = new WorkingNote(context, folderId);
+        note.setBgColorId(defaultBgColorId);
+        note.setWidgetId(widgetId);
+        note.setWidgetType(widgetType);
+        return note;
+    }
+
+    public static WorkingNote load(Context context, long id) {
+        return new WorkingNote(context, id, 0);
+    }
+
+    public synchronized boolean saveNote() {
+        if (isWorthSaving()) {
+            if (!existInDatabase()) {
+                if ((mNoteId = Note.getNewNoteId(mContext, mFolderId)) == 0) {
+                    Log.e(TAG, "Create new note fail with id:" + mNoteId);
+                    return false;
+                }
+            }
+
+            mNote.syncNote(mContext, mNoteId);
+
+            /**
+             * Update widget content if there exist any widget of this note
+             */
+            if (mWidgetId != AppWidgetManager.INVALID_APPWIDGET_ID
+                    && mWidgetType != Notes.TYPE_WIDGET_INVALIDE
+                    && mNoteSettingStatusListener != null) {
+                mNoteSettingStatusListener.onWidgetChanged();
+            }
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    public boolean existInDatabase() {
+        return mNoteId > 0;
+    }
+
+    private boolean isWorthSaving() {
+        if (mIsDeleted || (!existInDatabase() && TextUtils.isEmpty(mContent))
+                || (existInDatabase() && !mNote.isLocalModified())) {
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    public void setOnSettingStatusChangedListener(NoteSettingChangedListener l) {
+        mNoteSettingStatusListener = l;
+    }
+
+    public void setAlertDate(long date, boolean set) {
+        if (date != mAlertDate) {
+            mAlertDate = date;
+            mNote.setNoteValue(NoteColumns.ALERTED_DATE, String.valueOf(mAlertDate));
+        }
+        if (mNoteSettingStatusListener != null) {
+            mNoteSettingStatusListener.onClockAlertChanged(date, set);
+        }
+    }
+
+    public void markDeleted(boolean mark) {
+        mIsDeleted = mark;
+        if (mWidgetId != AppWidgetManager.INVALID_APPWIDGET_ID
+                && mWidgetType != Notes.TYPE_WIDGET_INVALIDE && mNoteSettingStatusListener != null) {
+                mNoteSettingStatusListener.onWidgetChanged();
+        }
+    }
+
+    public void setBgColorId(int id) {
+        if (id != mBgColorId) {
+            mBgColorId = id;
+            if (mNoteSettingStatusListener != null) {
+                mNoteSettingStatusListener.onBackgroundColorChanged();
+            }
+            mNote.setNoteValue(NoteColumns.BG_COLOR_ID, String.valueOf(id));
+        }
+    }
+
+    public void setCheckListMode(int mode) {
+        if (mMode != mode) {
+            if (mNoteSettingStatusListener != null) {
+                mNoteSettingStatusListener.onCheckListModeChanged(mMode, mode);
+            }
+            mMode = mode;
+            mNote.setTextData(TextNote.MODE, String.valueOf(mMode));
+        }
+    }
+
+    public void setWidgetType(int type) {
+        if (type != mWidgetType) {
+            mWidgetType = type;
+            mNote.setNoteValue(NoteColumns.WIDGET_TYPE, String.valueOf(mWidgetType));
+        }
+    }
+
+    public void setWidgetId(int id) {
+        if (id != mWidgetId) {
+            mWidgetId = id;
+            mNote.setNoteValue(NoteColumns.WIDGET_ID, String.valueOf(mWidgetId));
+        }
+    }
+
+    public void setWorkingText(String text) {
+        if (!TextUtils.equals(mContent, text)) {
+            mContent = text;
+            mNote.setTextData(DataColumns.CONTENT, mContent);
+        }
+    }
+
+    public void convertToCallNote(String phoneNumber, long callDate) {
+        mNote.setCallData(CallNote.CALL_DATE, String.valueOf(callDate));
+        mNote.setCallData(CallNote.PHONE_NUMBER, phoneNumber);
+        mNote.setNoteValue(NoteColumns.PARENT_ID, String.valueOf(Notes.ID_CALL_RECORD_FOLDER));
+    }
+
+    public boolean hasClockAlert() {
+        return (mAlertDate > 0 ? true : false);
+    }
+
+    public String getContent() {
+        return mContent;
+    }
+
+    public long getAlertDate() {
+        return mAlertDate;
+    }
+
+    public long getModifiedDate() {
+        return mModifiedDate;
+    }
+
+    public int getBgColorResId() {
+        return NoteBgResources.getNoteBgResource(mBgColorId);
+    }
+
+    public int getBgColorId() {
+        return mBgColorId;
+    }
+
+    public int getTitleBgResId() {
+        return NoteBgResources.getNoteTitleBgResource(mBgColorId);
+    }
+
+    public int getCheckListMode() {
+        return mMode;
+    }
+
+    public long getNoteId() {
+        return mNoteId;
+    }
+
+    public long getFolderId() {
+        return mFolderId;
+    }
+
+    public int getWidgetId() {
+        return mWidgetId;
+    }
+
+    public int getWidgetType() {
+        return mWidgetType;
+    }
+
+    public interface NoteSettingChangedListener {
+        /**
+         * Called when the background color of current note has just changed
+         */
+        void onBackgroundColorChanged();
+
+        /**
+         * Called when user set clock
+         */
+        void onClockAlertChanged(long date, boolean set);
+
+        /**
+         * Call when user create note from widget
+         */
+        void onWidgetChanged();
+
+        /**
+         * Call when switch between check list mode and normal mode
+         * @param oldMode is previous mode before change
+         * @param newMode is new mode
+         */
+        void onCheckListModeChanged(int oldMode, int newMode);
+    }
+}

java/net/micode/notes/tool/BackupUtils.java

@@ -0,0 +1,382 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 函数分析
+getInstance方法
+所属类：BackupUtils
+功能：实现单例模式，若实例sInstance为空，则创建并返回新的BackupUtils实例（传入Context进行初始化），若不为空则直接返回已有实例，保证整个应用中该工具类只有一个实例在运作。
+externalStorageAvailable方法
+所属类：BackupUtils
+功能：通过判断外部存储（通常是 SD 卡）的挂载状态是否为Environment.MEDIA_MOUNTED，来返回外部存储是否可用的布尔值，为后续备份操作判断能否将数据写入外部存储做准备。
+exportToText方法
+所属类：BackupUtils
+功能：调用内部TextExport类的exportToText方法来执行将笔记数据导出为文本的实际操作，并返回相应的状态码（如成功、外部存储未挂载、系统错误等），外部代码可据此知晓此次导出操作的结果情况。
+getExportedTextFileName方法
+所属类：BackupUtils
+功能：返回内部TextExport类中记录的导出文本文件名（mFileName），方便外部获取导出文件的名称信息，比如用于展示给用户或者进行后续文件相关的操作提示等。
+getExportedTextFileDir方法
+所属类：BackupUtils
+功能：返回内部TextExport类中记录的导出文本文件所在目录（mFileDirectory），用于知晓文件保存的路径情况，像在日志记录或者引导用户查找备份文件时能提供相应的目录信息。
+TextExport类相关函数
+构造函数：
+所属类：TextExport（BackupUtils的内部类）
+功能：初始化TEXT_FORMAT数组，从资源中获取格式化字符串数组用于后续文本格式化输出，同时保存传入的Context，并初始化文件名和文件目录为空字符串，为后续操作准备相关数据和资源引用。
+getFormat方法：
+所属类：TextExport（BackupUtils的内部类）
+功能：根据传入的id参数，从TEXT_FORMAT数组中获取对应的格式化字符串并返回，用于在文本输出时按照特定格式拼接内容，比如格式化日期、内容等信息。
+exportFolderToText方法：
+所属类：TextExport（BackupUtils的内部类）
+功能：依据传入的文件夹ID查询属于该文件夹的笔记游标，若游标不为null且有数据，遍历游标，先按格式输出笔记的修改日期，再根据笔记ID调用exportNoteToText方法输出笔记具体内容，最后关闭游标，实现将指定文件夹下所有笔记数据输出到给定的打印流中的功能。
+exportNoteToText方法：
+所属类：TextExport（BackupUtils的内部类）
+功能：依据传入的笔记ID查询该笔记附属数据的游标，若游标不为null且有数据，遍历游标，根据数据的MIME_TYPE判断类型（如通话记录、普通笔记等），按照对应格式输出相应数据（如电话号码、通话日期、笔记内容等），游标遍历完后关闭游标，并输出换行分隔符，完成单个笔记相关数据的文本输出操作。
+exportToText方法：
+所属类：TextExport（BackupUtils的内部类）
+功能：首先判断外部存储是否可用，不可用则返回对应状态码；接着获取用于输出文本的打印流，若获取失败返回系统错误状态码；然后分别查询符合特定条件的文件夹游标、根文件夹下笔记游标，遍历游标并调用相应的导出方法（exportFolderToText、exportNoteToText）输出数据，最后关闭打印流并返回成功状态码，整体实现将笔记数据按规则导出为文本文件的完整流程。
+getExportToTextPrintStream方法：
+所属类：TextExport（BackupUtils的内部类）
+功能：先创建一个基于外部存储指定路径和文件名（文件名含当前日期格式化信息）的文件，若创建失败则返回null，成功则记录文件名和文件目录信息，再尝试创建文件输出流并基于此构建打印流，若过程出现异常则返回null，最终返回构建好的用于输出文本的打印流，为文本导出提供输出流对象。
+generateFileMountedOnSDcard方法
+所属类：BackupUtils
+功能：根据传入的资源ID（用于指定文件路径、文件名格式）构建文件对象，先创建文件所在目录（若不存在），再创建文件本身（若不存在），若过程出现安全或IO异常则返回null，否则返回构建好的文件对象，用于在外部存储上生成保存备份数据的文本文件。
+ */
+
+package net.micode.notes.tool;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.os.Environment;
+import android.text.TextUtils;
+import android.text.format.DateFormat;
+import android.util.Log;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.DataConstants;
+import net.micode.notes.data.Notes.NoteColumns;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.PrintStream;
+
+
+public class BackupUtils {
+    private static final String TAG = "BackupUtils";
+    // Singleton stuff
+    private static BackupUtils sInstance;
+
+    public static synchronized BackupUtils getInstance(Context context) {
+        if (sInstance == null) {
+            sInstance = new BackupUtils(context);
+        }
+        return sInstance;
+    }
+
+    /**
+     * Following states are signs to represents backup or restore
+     * status
+     */
+    // Currently, the sdcard is not mounted
+    public static final int STATE_SD_CARD_UNMOUONTED           = 0;
+    // The backup file not exist
+    public static final int STATE_BACKUP_FILE_NOT_EXIST        = 1;
+    // The data is not well formated, may be changed by other programs
+    public static final int STATE_DATA_DESTROIED               = 2;
+    // Some run-time exception which causes restore or backup fails
+    public static final int STATE_SYSTEM_ERROR                 = 3;
+    // Backup or restore success
+    public static final int STATE_SUCCESS                      = 4;
+
+    private TextExport mTextExport;
+
+    private BackupUtils(Context context) {
+        mTextExport = new TextExport(context);
+    }
+
+    private static boolean externalStorageAvailable() {
+        return Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState());
+    }
+
+    public int exportToText() {
+        return mTextExport.exportToText();
+    }
+
+    public String getExportedTextFileName() {
+        return mTextExport.mFileName;
+    }
+
+    public String getExportedTextFileDir() {
+        return mTextExport.mFileDirectory;
+    }
+
+    private static class TextExport {
+        private static final String[] NOTE_PROJECTION = {
+                NoteColumns.ID,
+                NoteColumns.MODIFIED_DATE,
+                NoteColumns.SNIPPET,
+                NoteColumns.TYPE
+        };
+
+        private static final int NOTE_COLUMN_ID = 0;
+
+        private static final int NOTE_COLUMN_MODIFIED_DATE = 1;
+
+        private static final int NOTE_COLUMN_SNIPPET = 2;
+
+        private static final String[] DATA_PROJECTION = {
+                DataColumns.CONTENT,
+                DataColumns.MIME_TYPE,
+                DataColumns.DATA1,
+                DataColumns.DATA2,
+                DataColumns.DATA3,
+                DataColumns.DATA4,
+        };
+
+        private static final int DATA_COLUMN_CONTENT = 0;
+
+        private static final int DATA_COLUMN_MIME_TYPE = 1;
+
+        private static final int DATA_COLUMN_CALL_DATE = 2;
+
+        private static final int DATA_COLUMN_PHONE_NUMBER = 4;
+
+        private final String [] TEXT_FORMAT;
+        private static final int FORMAT_FOLDER_NAME          = 0;
+        private static final int FORMAT_NOTE_DATE            = 1;
+        private static final int FORMAT_NOTE_CONTENT         = 2;
+
+        private Context mContext;
+        private String mFileName;
+        private String mFileDirectory;
+
+        public TextExport(Context context) {
+            TEXT_FORMAT = context.getResources().getStringArray(R.array.format_for_exported_note);
+            mContext = context;
+            mFileName = "";
+            mFileDirectory = "";
+        }
+
+        private String getFormat(int id) {
+            return TEXT_FORMAT[id];
+        }
+
+        /**
+         * Export the folder identified by folder id to text
+         */
+        private void exportFolderToText(String folderId, PrintStream ps) {
+            // Query notes belong to this folder
+            Cursor notesCursor = mContext.getContentResolver().query(Notes.CONTENT_NOTE_URI,
+                    NOTE_PROJECTION, NoteColumns.PARENT_ID + "=?", new String[] {
+                        folderId
+                    }, null);
+
+            if (notesCursor != null) {
+                if (notesCursor.moveToFirst()) {
+                    do {
+                        // Print note's last modified date
+                        ps.println(String.format(getFormat(FORMAT_NOTE_DATE), DateFormat.format(
+                                mContext.getString(R.string.format_datetime_mdhm),
+                                notesCursor.getLong(NOTE_COLUMN_MODIFIED_DATE))));
+                        // Query data belong to this note
+                        String noteId = notesCursor.getString(NOTE_COLUMN_ID);
+                        exportNoteToText(noteId, ps);
+                    } while (notesCursor.moveToNext());
+                }
+                notesCursor.close();
+            }
+        }
+
+        /**
+         * Export note identified by id to a print stream
+         */
+        private void exportNoteToText(String noteId, PrintStream ps) {
+            Cursor dataCursor = mContext.getContentResolver().query(Notes.CONTENT_DATA_URI,
+                    DATA_PROJECTION, DataColumns.NOTE_ID + "=?", new String[] {
+                        noteId
+                    }, null);
+
+            if (dataCursor != null) {
+                if (dataCursor.moveToFirst()) {
+                    do {
+                        String mimeType = dataCursor.getString(DATA_COLUMN_MIME_TYPE);
+                        if (DataConstants.CALL_NOTE.equals(mimeType)) {
+                            // Print phone number
+                            String phoneNumber = dataCursor.getString(DATA_COLUMN_PHONE_NUMBER);
+                            long callDate = dataCursor.getLong(DATA_COLUMN_CALL_DATE);
+                            String location = dataCursor.getString(DATA_COLUMN_CONTENT);
+
+                            if (!TextUtils.isEmpty(phoneNumber)) {
+                                ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT),
+                                        phoneNumber));
+                            }
+                            // Print call date
+                            ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT), DateFormat
+                                    .format(mContext.getString(R.string.format_datetime_mdhm),
+                                            callDate)));
+                            // Print call attachment location
+                            if (!TextUtils.isEmpty(location)) {
+                                ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT),
+                                        location));
+                            }
+                        } else if (DataConstants.NOTE.equals(mimeType)) {
+                            String content = dataCursor.getString(DATA_COLUMN_CONTENT);
+                            if (!TextUtils.isEmpty(content)) {
+                                ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT),
+                                        content));
+                            }
+                        }
+                    } while (dataCursor.moveToNext());
+                }
+                dataCursor.close();
+            }
+            // print a line separator between note
+            try {
+                ps.write(new byte[] {
+                        Character.LINE_SEPARATOR, Character.LETTER_NUMBER
+                });
+            } catch (IOException e) {
+                Log.e(TAG, e.toString());
+            }
+        }
+
+        /**
+         * Note will be exported as text which is user readable
+         */
+        public int exportToText() {
+            if (!externalStorageAvailable()) {
+                Log.d(TAG, "Media was not mounted");
+                return STATE_SD_CARD_UNMOUONTED;
+            }
+
+            PrintStream ps = getExportToTextPrintStream();
+            if (ps == null) {
+                Log.e(TAG, "get print stream error");
+                return STATE_SYSTEM_ERROR;
+            }
+            // First export folder and its notes
+            Cursor folderCursor = mContext.getContentResolver().query(
+                    Notes.CONTENT_NOTE_URI,
+                    NOTE_PROJECTION,
+                    "(" + NoteColumns.TYPE + "=" + Notes.TYPE_FOLDER + " AND "
+                            + NoteColumns.PARENT_ID + "<>" + Notes.ID_TRASH_FOLER + ") OR "
+                            + NoteColumns.ID + "=" + Notes.ID_CALL_RECORD_FOLDER, null, null);
+
+            if (folderCursor != null) {
+                if (folderCursor.moveToFirst()) {
+                    do {
+                        // Print folder's name
+                        String folderName = "";
+                        if(folderCursor.getLong(NOTE_COLUMN_ID) == Notes.ID_CALL_RECORD_FOLDER) {
+                            folderName = mContext.getString(R.string.call_record_folder_name);
+                        } else {
+                            folderName = folderCursor.getString(NOTE_COLUMN_SNIPPET);
+                        }
+                        if (!TextUtils.isEmpty(folderName)) {
+                            ps.println(String.format(getFormat(FORMAT_FOLDER_NAME), folderName));
+                        }
+                        String folderId = folderCursor.getString(NOTE_COLUMN_ID);
+                        exportFolderToText(folderId, ps);
+                    } while (folderCursor.moveToNext());
+                }
+                folderCursor.close();
+            }
+
+            // Export notes in root's folder
+            Cursor noteCursor = mContext.getContentResolver().query(
+                    Notes.CONTENT_NOTE_URI,
+                    NOTE_PROJECTION,
+                    NoteColumns.TYPE + "=" + +Notes.TYPE_NOTE + " AND " + NoteColumns.PARENT_ID
+                            + "=0", null, null);
+
+            if (noteCursor != null) {
+                if (noteCursor.moveToFirst()) {
+                    do {
+                        ps.println(String.format(getFormat(FORMAT_NOTE_DATE), DateFormat.format(
+                                mContext.getString(R.string.format_datetime_mdhm),
+                                noteCursor.getLong(NOTE_COLUMN_MODIFIED_DATE))));
+                        // Query data belong to this note
+                        String noteId = noteCursor.getString(NOTE_COLUMN_ID);
+                        exportNoteToText(noteId, ps);
+                    } while (noteCursor.moveToNext());
+                }
+                noteCursor.close();
+            }
+            ps.close();
+
+            return STATE_SUCCESS;
+        }
+
+        /**
+         * Get a print stream pointed to the file {@generateExportedTextFile}
+         */
+        private PrintStream getExportToTextPrintStream() {
+            File file = generateFileMountedOnSDcard(mContext, R.string.file_path,
+                    R.string.file_name_txt_format);
+            if (file == null) {
+                Log.e(TAG, "create file to exported failed");
+                return null;
+            }
+            mFileName = file.getName();
+            mFileDirectory = mContext.getString(R.string.file_path);
+            PrintStream ps = null;
+            try {
+                FileOutputStream fos = new FileOutputStream(file);
+                ps = new PrintStream(fos);
+            } catch (FileNotFoundException e) {
+                e.printStackTrace();
+                return null;
+            } catch (NullPointerException e) {
+                e.printStackTrace();
+                return null;
+            }
+            return ps;
+        }
+    }
+
+    /**
+     * Generate the text file to store imported data
+     */
+    private static File generateFileMountedOnSDcard(Context context, int filePathResId, int fileNameFormatResId) {
+        StringBuilder sb = new StringBuilder();
+        sb.append(Environment.getExternalStorageDirectory());
+        sb.append(context.getString(filePathResId));
+        File filedir = new File(sb.toString());
+        sb.append(context.getString(
+                fileNameFormatResId,
+                DateFormat.format(context.getString(R.string.format_date_ymd),
+                        System.currentTimeMillis())));
+        File file = new File(sb.toString());
+
+        try {
+            if (!filedir.exists()) {
+                filedir.mkdir();
+            }
+            if (!file.exists()) {
+                file.createNewFile();
+            }
+            return file;
+        } catch (SecurityException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+        return null;
+    }
+}
+
+

java/net/micode/notes/tool/DataUtils.java

@@ -0,0 +1,337 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *总体分析
+这段 Java 代码定义了DataUtils类，提供诸多处理笔记相关数据的实用方法，借助ContentResolver与对应数据存储交互，涵盖笔记删除、移动、存在性判断及数据获取等功能，便于安卓笔记应用的数据操作管理。
+函数分析
+batchDeleteNotes方法
+所属类：DataUtils
+功能：对传入要删笔记的ID集合判空、长度判断，构建操作列表批量删笔记，按执行结果返回布尔值表成败，遇异常记日志并返回false。
+moveNoteToFoler方法
+所属类：DataUtils
+功能：创建ContentValues存更新数据，用ContentResolver按传入ID更新对应笔记信息，实现单笔记移至指定文件夹。
+batchMoveToFolder方法
+所属类：DataUtils
+功能：判传入移动笔记ID集合是否为空，构建操作列表批量更新操作，依执行结果返回布尔值，异常时记日志返回false。
+getUserFolderCount方法
+所属类：DataUtils
+功能：用ContentResolver查询符合条件的文件夹记录数量，游标获取并返回数量，用于统计有效文件夹个数。
+visibleInNoteDatabase方法
+所属类：DataUtils
+功能：通过ContentResolver查询判断笔记是否符合条件在数据库中可见，依游标记录数量返回布尔值。
+existInNoteDatabase方法
+所属类：DataUtils
+功能：借ContentResolver查询笔记是否存在，据游标记录数量返回布尔值。
+existInDataDatabase方法
+所属类：DataUtils
+功能：类似查笔记存在的方式，查数据在对应数据库中是否存在，依游标返回布尔值。
+checkVisibleFolderName方法
+所属类：DataUtils
+功能：用ContentResolver查指定名称文件夹是否符合条件存在，依游标记录数量返回布尔值。
+getFolderNoteWidget方法
+所属类：DataUtils
+功能：ContentResolver查指定文件夹下笔记部件属性，游标遍历封装属性到集合后返回。
+getCallNumberByNoteId方法
+所属类：DataUtils
+功能：ContentResolver按条件查对应笔记关联电话号码，游标获取返回，无则返回空字符串。
+getNoteIdByPhoneNumberAndCallDate方法
+所属类：DataUtils
+功能：ContentResolver依通话相关条件查对应笔记ID，游标获取返回，无则返回0。
+getSnippetById方法
+所属类：DataUtils
+功能：ContentResolver查指定笔记内容片段，游标获取返回，无则抛异常。
+getFormattedSnippet方法
+所属类：DataUtils
+功能：格式化传入笔记内容片段，去除两端空白，遇换行截取前面部分后返回。
+ */
+
+package net.micode.notes.tool;
+
+import android.content.ContentProviderOperation;
+import android.content.ContentProviderResult;
+import android.content.ContentResolver;
+import android.content.ContentUris;
+import android.content.ContentValues;
+import android.content.OperationApplicationException;
+import android.database.Cursor;
+import android.os.RemoteException;
+import android.util.Log;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.CallNote;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.ui.NotesListAdapter.AppWidgetAttribute;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+
+
+public class DataUtils {
+    public static final String TAG = "DataUtils";
+    public static boolean batchDeleteNotes(ContentResolver resolver, HashSet<Long> ids) {
+        if (ids == null) {
+            Log.d(TAG, "the ids is null");
+            return true;
+        }
+        if (ids.size() == 0) {
+            Log.d(TAG, "no id is in the hashset");
+            return true;
+        }
+
+        ArrayList<ContentProviderOperation> operationList = new ArrayList<ContentProviderOperation>();
+        for (long id : ids) {
+            if(id == Notes.ID_ROOT_FOLDER) {
+                Log.e(TAG, "Don't delete system folder root");
+                continue;
+            }
+            ContentProviderOperation.Builder builder = ContentProviderOperation
+                    .newDelete(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id));
+            operationList.add(builder.build());
+        }
+        try {
+            ContentProviderResult[] results = resolver.applyBatch(Notes.AUTHORITY, operationList);
+            if (results == null || results.length == 0 || results[0] == null) {
+                Log.d(TAG, "delete notes failed, ids:" + ids.toString());
+                return false;
+            }
+            return true;
+        } catch (RemoteException e) {
+            Log.e(TAG, String.format("%s: %s", e.toString(), e.getMessage()));
+        } catch (OperationApplicationException e) {
+            Log.e(TAG, String.format("%s: %s", e.toString(), e.getMessage()));
+        }
+        return false;
+    }
+
+    public static void moveNoteToFoler(ContentResolver resolver, long id, long srcFolderId, long desFolderId) {
+        ContentValues values = new ContentValues();
+        values.put(NoteColumns.PARENT_ID, desFolderId);
+        values.put(NoteColumns.ORIGIN_PARENT_ID, srcFolderId);
+        values.put(NoteColumns.LOCAL_MODIFIED, 1);
+        resolver.update(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id), values, null, null);
+    }
+
+    public static boolean batchMoveToFolder(ContentResolver resolver, HashSet<Long> ids,
+            long folderId) {
+        if (ids == null) {
+            Log.d(TAG, "the ids is null");
+            return true;
+        }
+
+        ArrayList<ContentProviderOperation> operationList = new ArrayList<ContentProviderOperation>();
+        for (long id : ids) {
+            ContentProviderOperation.Builder builder = ContentProviderOperation
+                    .newUpdate(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id));
+            builder.withValue(NoteColumns.PARENT_ID, folderId);
+            builder.withValue(NoteColumns.LOCAL_MODIFIED, 1);
+            operationList.add(builder.build());
+        }
+
+        try {
+            ContentProviderResult[] results = resolver.applyBatch(Notes.AUTHORITY, operationList);
+            if (results == null || results.length == 0 || results[0] == null) {
+                Log.d(TAG, "delete notes failed, ids:" + ids.toString());
+                return false;
+            }
+            return true;
+        } catch (RemoteException e) {
+            Log.e(TAG, String.format("%s: %s", e.toString(), e.getMessage()));
+        } catch (OperationApplicationException e) {
+            Log.e(TAG, String.format("%s: %s", e.toString(), e.getMessage()));
+        }
+        return false;
+    }
+
+    /**
+     * Get the all folder count except system folders {@link Notes#TYPE_SYSTEM}}
+     */
+    public static int getUserFolderCount(ContentResolver resolver) {
+        Cursor cursor =resolver.query(Notes.CONTENT_NOTE_URI,
+                new String[] { "COUNT(*)" },
+                NoteColumns.TYPE + "=? AND " + NoteColumns.PARENT_ID + "<>?",
+                new String[] { String.valueOf(Notes.TYPE_FOLDER), String.valueOf(Notes.ID_TRASH_FOLER)},
+                null);
+
+        int count = 0;
+        if(cursor != null) {
+            if(cursor.moveToFirst()) {
+                try {
+                    count = cursor.getInt(0);
+                } catch (IndexOutOfBoundsException e) {
+                    Log.e(TAG, "get folder count failed:" + e.toString());
+                } finally {
+                    cursor.close();
+                }
+            }
+        }
+        return count;
+    }
+
+    public static boolean visibleInNoteDatabase(ContentResolver resolver, long noteId, int type) {
+        Cursor cursor = resolver.query(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId),
+                null,
+                NoteColumns.TYPE + "=? AND " + NoteColumns.PARENT_ID + "<>" + Notes.ID_TRASH_FOLER,
+                new String [] {String.valueOf(type)},
+                null);
+
+        boolean exist = false;
+        if (cursor != null) {
+            if (cursor.getCount() > 0) {
+                exist = true;
+            }
+            cursor.close();
+        }
+        return exist;
+    }
+
+    public static boolean existInNoteDatabase(ContentResolver resolver, long noteId) {
+        Cursor cursor = resolver.query(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId),
+                null, null, null, null);
+
+        boolean exist = false;
+        if (cursor != null) {
+            if (cursor.getCount() > 0) {
+                exist = true;
+            }
+            cursor.close();
+        }
+        return exist;
+    }
+
+    public static boolean existInDataDatabase(ContentResolver resolver, long dataId) {
+        Cursor cursor = resolver.query(ContentUris.withAppendedId(Notes.CONTENT_DATA_URI, dataId),
+                null, null, null, null);
+
+        boolean exist = false;
+        if (cursor != null) {
+            if (cursor.getCount() > 0) {
+                exist = true;
+            }
+            cursor.close();
+        }
+        return exist;
+    }
+
+    public static boolean checkVisibleFolderName(ContentResolver resolver, String name) {
+        Cursor cursor = resolver.query(Notes.CONTENT_NOTE_URI, null,
+                NoteColumns.TYPE + "=" + Notes.TYPE_FOLDER +
+                " AND " + NoteColumns.PARENT_ID + "<>" + Notes.ID_TRASH_FOLER +
+                " AND " + NoteColumns.SNIPPET + "=?",
+                new String[] { name }, null);
+        boolean exist = false;
+        if(cursor != null) {
+            if(cursor.getCount() > 0) {
+                exist = true;
+            }
+            cursor.close();
+        }
+        return exist;
+    }
+
+    public static HashSet<AppWidgetAttribute> getFolderNoteWidget(ContentResolver resolver, long folderId) {
+        Cursor c = resolver.query(Notes.CONTENT_NOTE_URI,
+                new String[] { NoteColumns.WIDGET_ID, NoteColumns.WIDGET_TYPE },
+                NoteColumns.PARENT_ID + "=?",
+                new String[] { String.valueOf(folderId) },
+                null);
+
+        HashSet<AppWidgetAttribute> set = null;
+        if (c != null) {
+            if (c.moveToFirst()) {
+                set = new HashSet<AppWidgetAttribute>();
+                do {
+                    try {
+                        AppWidgetAttribute widget = new AppWidgetAttribute();
+                        widget.widgetId = c.getInt(0);
+                        widget.widgetType = c.getInt(1);
+                        set.add(widget);
+                    } catch (IndexOutOfBoundsException e) {
+                        Log.e(TAG, e.toString());
+                    }
+                } while (c.moveToNext());
+            }
+            c.close();
+        }
+        return set;
+    }
+
+    public static String getCallNumberByNoteId(ContentResolver resolver, long noteId) {
+        Cursor cursor = resolver.query(Notes.CONTENT_DATA_URI,
+                new String [] { CallNote.PHONE_NUMBER },
+                CallNote.NOTE_ID + "=? AND " + CallNote.MIME_TYPE + "=?",
+                new String [] { String.valueOf(noteId), CallNote.CONTENT_ITEM_TYPE },
+                null);
+
+        if (cursor != null && cursor.moveToFirst()) {
+            try {
+                return cursor.getString(0);
+            } catch (IndexOutOfBoundsException e) {
+                Log.e(TAG, "Get call number fails " + e.toString());
+            } finally {
+                cursor.close();
+            }
+        }
+        return "";
+    }
+
+    public static long getNoteIdByPhoneNumberAndCallDate(ContentResolver resolver, String phoneNumber, long callDate) {
+        Cursor cursor = resolver.query(Notes.CONTENT_DATA_URI,
+                new String [] { CallNote.NOTE_ID },
+                CallNote.CALL_DATE + "=? AND " + CallNote.MIME_TYPE + "=? AND PHONE_NUMBERS_EQUAL("
+                + CallNote.PHONE_NUMBER + ",?)",
+                new String [] { String.valueOf(callDate), CallNote.CONTENT_ITEM_TYPE, phoneNumber },
+                null);
+
+        if (cursor != null) {
+            if (cursor.moveToFirst()) {
+                try {
+                    return cursor.getLong(0);
+                } catch (IndexOutOfBoundsException e) {
+                    Log.e(TAG, "Get call note id fails " + e.toString());
+                }
+            }
+            cursor.close();
+        }
+        return 0;
+    }
+
+    public static String getSnippetById(ContentResolver resolver, long noteId) {
+        Cursor cursor = resolver.query(Notes.CONTENT_NOTE_URI,
+                new String [] { NoteColumns.SNIPPET },
+                NoteColumns.ID + "=?",
+                new String [] { String.valueOf(noteId)},
+                null);
+
+        if (cursor != null) {
+            String snippet = "";
+            if (cursor.moveToFirst()) {
+                snippet = cursor.getString(0);
+            }
+            cursor.close();
+            return snippet;
+        }
+        throw new IllegalArgumentException("Note is not found with id: " + noteId);
+    }
+
+    public static String getFormattedSnippet(String snippet) {
+        if (snippet != null) {
+            snippet = snippet.trim();
+            int index = snippet.indexOf('\n');
+            if (index != -1) {
+                snippet = snippet.substring(0, index);
+            }
+        }
+        return snippet;
+    }
+}

java/net/micode/notes/tool/GTaskStringUtils.java

@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 这段 Java 代码定义了GTaskStringUtils类，其主要作用是作为一个常量定义的工具类，用于集中存放与 GTask 相关的 JSON 数据交互以及笔记相关的一些特定字符串常量。这些常量涵盖了 GTask 操作中如动作类型（创建、获取全部、移动、更新等）、各种实体相关属性（如 ID、名称、父 ID 等）的键名，还有针对特定文件夹、元数据等方面的标识字符串，方便在整个应用中涉及到 GTask 数据处理、笔记分类及元数据管理等业务逻辑时统一引用这些常量，增强代码的可读性与可维护性，避免在不同地方使用硬编码字符串而导致的潜在错误和修改不便等问题。
+ */
+
+package net.micode.notes.tool;
+
+public class GTaskStringUtils {
+
+    public final static String GTASK_JSON_ACTION_ID = "action_id";
+
+    public final static String GTASK_JSON_ACTION_LIST = "action_list";
+
+    public final static String GTASK_JSON_ACTION_TYPE = "action_type";
+
+    public final static String GTASK_JSON_ACTION_TYPE_CREATE = "create";
+
+    public final static String GTASK_JSON_ACTION_TYPE_GETALL = "get_all";
+
+    public final static String GTASK_JSON_ACTION_TYPE_MOVE = "move";
+
+    public final static String GTASK_JSON_ACTION_TYPE_UPDATE = "update";
+
+    public final static String GTASK_JSON_CREATOR_ID = "creator_id";
+
+    public final static String GTASK_JSON_CHILD_ENTITY = "child_entity";
+
+    public final static String GTASK_JSON_CLIENT_VERSION = "client_version";
+
+    public final static String GTASK_JSON_COMPLETED = "completed";
+
+    public final static String GTASK_JSON_CURRENT_LIST_ID = "current_list_id";
+
+    public final static String GTASK_JSON_DEFAULT_LIST_ID = "default_list_id";
+
+    public final static String GTASK_JSON_DELETED = "deleted";
+
+    public final static String GTASK_JSON_DEST_LIST = "dest_list";
+
+    public final static String GTASK_JSON_DEST_PARENT = "dest_parent";
+
+    public final static String GTASK_JSON_DEST_PARENT_TYPE = "dest_parent_type";
+
+    public final static String GTASK_JSON_ENTITY_DELTA = "entity_delta";
+
+    public final static String GTASK_JSON_ENTITY_TYPE = "entity_type";
+
+    public final static String GTASK_JSON_GET_DELETED = "get_deleted";
+
+    public final static String GTASK_JSON_ID = "id";
+
+    public final static String GTASK_JSON_INDEX = "index";
+
+    public final static String GTASK_JSON_LAST_MODIFIED = "last_modified";
+
+    public final static String GTASK_JSON_LATEST_SYNC_POINT = "latest_sync_point";
+
+    public final static String GTASK_JSON_LIST_ID = "list_id";
+
+    public final static String GTASK_JSON_LISTS = "lists";
+
+    public final static String GTASK_JSON_NAME = "name";
+
+    public final static String GTASK_JSON_NEW_ID = "new_id";
+
+    public final static String GTASK_JSON_NOTES = "notes";
+
+    public final static String GTASK_JSON_PARENT_ID = "parent_id";
+
+    public final static String GTASK_JSON_PRIOR_SIBLING_ID = "prior_sibling_id";
+
+    public final static String GTASK_JSON_RESULTS = "results";
+
+    public final static String GTASK_JSON_SOURCE_LIST = "source_list";
+
+    public final static String GTASK_JSON_TASKS = "tasks";
+
+    public final static String GTASK_JSON_TYPE = "type";
+
+    public final static String GTASK_JSON_TYPE_GROUP = "GROUP";
+
+    public final static String GTASK_JSON_TYPE_TASK = "TASK";
+
+    public final static String GTASK_JSON_USER = "user";
+
+    public final static String MIUI_FOLDER_PREFFIX = "[MIUI_Notes]";
+
+    public final static String FOLDER_DEFAULT = "Default";
+
+    public final static String FOLDER_CALL_NOTE = "Call_Note";
+
+    public final static String FOLDER_META = "METADATA";
+
+    public final static String META_HEAD_GTASK_ID = "meta_gid";
+
+    public final static String META_HEAD_NOTE = "meta_note";
+
+    public final static String META_HEAD_DATA = "meta_data";
+
+    public final static String META_NOTE_NAME = "[META INFO] DON'T UPDATE AND DELETE";
+
+}

java/net/micode/notes/tool/ResourceParser.java

@@ -0,0 +1,210 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了ResourceParser类，主要用于对应用中的各类资源（如背景图片资源、文本外观样式资源等）进行管理与解析，方便根据不同的条件获取对应的资源标识符（如资源 ID）。它内部定义了多个静态内部类，分别针对笔记背景、笔记项背景、部件背景以及文本外观等不同方面的资源进行组织，同时还定义了一些表示默认状态（如默认颜色、默认字体大小等）的常量。通过结合应用的偏好设置等逻辑，可以灵活地获取相应的资源 ID，为实现界面的多样化显示（例如不同颜色主题、不同字体大小展示等）提供了资源获取的统一入口，有助于提升代码在资源管理方面的可维护性和可扩展性。
+函数分析
+NoteBgResources类相关函数
+所属类：ResourceParser.NoteBgResources（ResourceParser的内部类）
+功能：
+getNoteBgResource方法：根据传入的id参数，从预定义的BG_EDIT_RESOURCES数组中获取对应的笔记编辑背景资源的ID并返回，用于获取指定的笔记编辑背景相关资源。
+getNoteTitleBgResource方法：依据传入的id参数，从BG_EDIT_TITLE_RESOURCES数组中获取对应的笔记标题编辑背景资源的ID并返回，方便获取相应的笔记标题编辑背景资源。
+getDefaultBgId方法
+所属类：ResourceParser
+功能：通过获取应用的默认共享偏好设置，判断是否开启了特定的背景颜色随机设置的偏好项（NotesPreferenceActivity.PREFERENCE_SET_BG_COLOR_KEY对应的布尔值），若开启则随机生成一个在NoteBgResources.BG_EDIT_RESOURCES数组长度范围内的索引值作为背景ID返回，若未开启则返回默认的背景颜色ID（BG_DEFAULT_COLOR），以此来确定默认的背景资源ID。
+NoteItemBgResources类相关函数
+所属类：ResourceParser.NoteItemBgResources（ResourceParser的内部类）
+功能：
+getNoteBgFirstRes方法：根据传入的id参数，从BG_FIRST_RESOURCES数组中获取对应的笔记项首行背景资源的ID并返回，用于获取特定的笔记项首行背景资源。
+getNoteBgLastRes方法：依据传入的id参数，从BG_LAST_RESOURCES数组中获取对应的笔记项末行背景资源的ID并返回，方便获取相应的笔记项末行背景资源。
+getNoteBgSingleRes方法：按照传入的id参数，从BG_SINGLE_RESOURCES数组中获取对应的单个笔记项背景资源的ID并返回，用于获取单个笔记项对应的背景资源。
+getNoteBgNormalRes方法：根据传入的id参数，从BG_NORMAL_RESOURCES数组中获取对应的笔记项普通行背景资源的ID并返回，便于获取笔记项普通行的背景资源。
+getFolderBgRes方法：直接返回代表文件夹背景资源的ID（R.drawable.list_folder），用于获取文件夹的背景资源。
+WidgetBgResources类相关函数
+所属类：ResourceParser.WidgetBgResources（ResourceParser的内部类）
+功能：
+getWidget2xBgResource方法：根据传入的id参数，从BG_2X_RESOURCES数组中获取对应的2x部件背景资源的ID并返回，用于获取相应尺寸部件的背景资源。
+getWidget4xBgResource方法：依据传入的id参数，从BG_4X_RESOURCES数组中获取对应的4x部件背景资源的ID并返回，方便获取特定尺寸部件的背景资源。
+TextAppearanceResources类相关函数
+所属类：ResourceParser.TextAppearanceResources（ResourceParser的内部类）
+功能：
+getTexAppearanceResource方法：根据传入的id参数，先判断该参数是否超出TEXTAPPEARANCE_RESOURCES数组长度范围，若超出则返回默认的字体大小对应的资源ID（BG_DEFAULT_FONT_SIZE），若未超出则从该数组中获取对应的文本外观资源的ID并返回，用于获取合适的文本外观样式资源。
+getResourcesSize方法：直接返回TEXTAPPEARANCE_RESOURCES数组的长度，用于知晓文本外观资源的数量情况。
+ */
+
+package net.micode.notes.tool;
+
+import android.content.Context;
+import android.preference.PreferenceManager;
+
+import net.micode.notes.R;
+import net.micode.notes.ui.NotesPreferenceActivity;
+
+public class ResourceParser {
+
+    public static final int YELLOW           = 0;
+    public static final int BLUE             = 1;
+    public static final int WHITE            = 2;
+    public static final int GREEN            = 3;
+    public static final int RED              = 4;
+
+    public static final int BG_DEFAULT_COLOR = YELLOW;
+
+    public static final int TEXT_SMALL       = 0;
+    public static final int TEXT_MEDIUM      = 1;
+    public static final int TEXT_LARGE       = 2;
+    public static final int TEXT_SUPER       = 3;
+
+    public static final int BG_DEFAULT_FONT_SIZE = TEXT_MEDIUM;
+
+    public static class NoteBgResources {
+        private final static int [] BG_EDIT_RESOURCES = new int [] {
+            R.drawable.edit_yellow,
+            R.drawable.edit_blue,
+            R.drawable.edit_white,
+            R.drawable.edit_green,
+            R.drawable.edit_red
+        };
+
+        private final static int [] BG_EDIT_TITLE_RESOURCES = new int [] {
+            R.drawable.edit_title_yellow,
+            R.drawable.edit_title_blue,
+            R.drawable.edit_title_white,
+            R.drawable.edit_title_green,
+            R.drawable.edit_title_red
+        };
+
+        public static int getNoteBgResource(int id) {
+            return BG_EDIT_RESOURCES[id];
+        }
+
+        public static int getNoteTitleBgResource(int id) {
+            return BG_EDIT_TITLE_RESOURCES[id];
+        }
+    }
+
+    public static int getDefaultBgId(Context context) {
+        if (PreferenceManager.getDefaultSharedPreferences(context).getBoolean(
+                NotesPreferenceActivity.PREFERENCE_SET_BG_COLOR_KEY, false)) {
+            return (int) (Math.random() * NoteBgResources.BG_EDIT_RESOURCES.length);
+        } else {
+            return BG_DEFAULT_COLOR;
+        }
+    }
+
+    public static class NoteItemBgResources {
+        private final static int [] BG_FIRST_RESOURCES = new int [] {
+            R.drawable.list_yellow_up,
+            R.drawable.list_blue_up,
+            R.drawable.list_white_up,
+            R.drawable.list_green_up,
+            R.drawable.list_red_up
+        };
+
+        private final static int [] BG_NORMAL_RESOURCES = new int [] {
+            R.drawable.list_yellow_middle,
+            R.drawable.list_blue_middle,
+            R.drawable.list_white_middle,
+            R.drawable.list_green_middle,
+            R.drawable.list_red_middle
+        };
+
+        private final static int [] BG_LAST_RESOURCES = new int [] {
+            R.drawable.list_yellow_down,
+            R.drawable.list_blue_down,
+            R.drawable.list_white_down,
+            R.drawable.list_green_down,
+            R.drawable.list_red_down,
+        };
+
+        private final static int [] BG_SINGLE_RESOURCES = new int [] {
+            R.drawable.list_yellow_single,
+            R.drawable.list_blue_single,
+            R.drawable.list_white_single,
+            R.drawable.list_green_single,
+            R.drawable.list_red_single
+        };
+
+        public static int getNoteBgFirstRes(int id) {
+            return BG_FIRST_RESOURCES[id];
+        }
+
+        public static int getNoteBgLastRes(int id) {
+            return BG_LAST_RESOURCES[id];
+        }
+
+        public static int getNoteBgSingleRes(int id) {
+            return BG_SINGLE_RESOURCES[id];
+        }
+
+        public static int getNoteBgNormalRes(int id) {
+            return BG_NORMAL_RESOURCES[id];
+        }
+
+        public static int getFolderBgRes() {
+            return R.drawable.list_folder;
+        }
+    }
+
+    public static class WidgetBgResources {
+        private final static int [] BG_2X_RESOURCES = new int [] {
+            R.drawable.widget_2x_yellow,
+            R.drawable.widget_2x_blue,
+            R.drawable.widget_2x_white,
+            R.drawable.widget_2x_green,
+            R.drawable.widget_2x_red,
+        };
+
+        public static int getWidget2xBgResource(int id) {
+            return BG_2X_RESOURCES[id];
+        }
+
+        private final static int [] BG_4X_RESOURCES = new int [] {
+            R.drawable.widget_4x_yellow,
+            R.drawable.widget_4x_blue,
+            R.drawable.widget_4x_white,
+            R.drawable.widget_4x_green,
+            R.drawable.widget_4x_red
+        };
+
+        public static int getWidget4xBgResource(int id) {
+            return BG_4X_RESOURCES[id];
+        }
+    }
+
+    public static class TextAppearanceResources {
+        private final static int [] TEXTAPPEARANCE_RESOURCES = new int [] {
+            R.style.TextAppearanceNormal,
+            R.style.TextAppearanceMedium,
+            R.style.TextAppearanceLarge,
+            R.style.TextAppearanceSuper
+        };
+
+        public static int getTexAppearanceResource(int id) {
+            /**
+             * HACKME: Fix bug of store the resource id in shared preference.
+             * The id may larger than the length of resources, in this case,
+             * return the {@link ResourceParser#BG_DEFAULT_FONT_SIZE}
+             */
+            if (id >= TEXTAPPEARANCE_RESOURCES.length) {
+                return BG_DEFAULT_FONT_SIZE;
+            }
+            return TEXTAPPEARANCE_RESOURCES[id];
+        }
+
+        public static int getResourcesSize() {
+            return TEXTAPPEARANCE_RESOURCES.length;
+        }
+    }
+}

java/net/micode/notes/ui/AlarmAlertActivity.java

@@ -0,0 +1,191 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 以下是这段代码中主要的函数及其功能介绍：
+onCreate 函数
+所属类：AlarmAlertActivity
+功能：
+首先调用父类（Activity）的 onCreate 方法进行基础的初始化操作。
+通过 requestWindowFeature 方法请求去除 Activity 的标题栏（使用 Window.FEATURE_NO_TITLE 特性）。
+获取当前窗口对象 win，并添加一些窗口相关的标志位，例如 FLAG_SHOW_WHEN_LOCKED 让窗口在屏幕锁定时也能显示，还会根据屏幕是否亮起（通过 isScreenOn 函数判断）来添加如 FLAG_KEEP_SCREEN_ON 等其他与屏幕状态控制相关的标志位，用于控制屏幕的显示和锁定等行为。
+从传入的 Intent 中获取相关数据，尝试解析出笔记的 ID（mNoteId）以及对应的简短内容片段（mSnippet），若解析出现 IllegalArgumentException 异常则打印堆栈信息并返回，不继续后续流程。
+创建 MediaPlayer 实例 mPlayer，接着判断笔记在数据库中的可见性（通过 DataUtils.visibleInNoteDatabase 函数判断），如果可见则调用 showActionDialog 显示操作对话框，并调用 playAlarmSound 播放闹钟声音，若不可见则直接结束当前 Activity。
+isScreenOn 函数
+所属类：AlarmAlertActivity
+功能：获取系统的电源管理服务（PowerManager），通过调用其 isScreenOn 方法来判断当前屏幕是否处于亮起状态，返回一个布尔值，用于后续决定添加哪些窗口相关的标志位等操作。
+playAlarmSound 函数
+所属类：AlarmAlertActivity
+功能：
+首先通过 RingtoneManager.getActualDefaultRingtoneUri 方法获取系统默认闹钟铃声的 Uri 地址。
+接着从系统设置中获取静音模式影响的音频流相关设置（通过 Settings.System.getInt 获取 Settings.System.MODE_RINGER_STREAMS_AFFECTED 的值），根据其值来设置 MediaPlayer（mPlayer）的音频流类型，若满足特定条件则设置为获取到的 silentModeStreams，否则设置为 AudioManager.STREAM_ALARM。
+然后尝试设置 MediaPlayer 的数据源（通过 setDataSource 方法传入当前 Activity 上下文和铃声 Uri），并进行准备（prepare）操作，设置为循环播放（setLooping 为 true），最后启动播放（start）。过程中如果出现如 IllegalArgumentException、SecurityException、IllegalStateException、IOException 等异常会打印相应的堆栈信息。
+showActionDialog 函数
+所属类：AlarmAlertActivity
+功能：
+创建一个 AlertDialog.Builder 实例用于构建对话框，设置对话框的标题（通过 R.string.app_name 资源字符串获取标题内容）、消息内容（使用之前获取的笔记内容片段 mSnippet）。
+设置对话框的确定按钮（通过 setPositiveButton 方法，按钮文本使用 R.string.notealert_ok 资源字符串，点击事件绑定到当前类实现的 onClick 方法），并且在屏幕亮起的情况下（通过 isScreenOn 函数判断），设置进入按钮（通过 setNegativeButton 方法，按钮文本使用 R.string.notealert_enter 资源字符串，点击事件同样绑定到 onClick 方法）。
+最后调用 show 方法显示对话框，并设置对话框关闭的监听器（通过 setOnDismissListener 绑定到当前类实现的 onDismiss 方法）。
+onClick 函数
+所属类：AlarmAlertActivity
+功能：实现了 DialogInterface.OnClickListener 接口的方法，根据点击对话框按钮的 which 参数进行不同操作。当点击了对话框的否定（消极）按钮（对应 DialogInterface.BUTTON_NEGATIVE，也就是 notealert_enter 按钮）时，创建一个新的 Intent，指定目标 Activity 为 NoteEditActivity，设置 Intent 的动作（ACTION_VIEW）以及传递笔记的 ID（通过 putExtra 传递 Intent.EXTRA_UID 附加数据），然后启动对应的 Activity，用于进入笔记编辑页面等相关操作。对于其他按钮点击情况暂时不做额外处理（default 分支）。
+onDismiss 函数
+所属类：AlarmAlertActivity
+功能：实现了 DialogInterface.OnDismissListener 接口的方法，当对话框关闭时被调用。在这个函数中，会调用 stopAlarmSound 函数停止正在播放的闹钟声音，然后结束当前 Activity，完成整个与闹钟提醒相关的流程清理和关闭操作。
+stopAlarmSound 函数
+所属类：AlarmAlertActivity
+功能：用于停止并释放 MediaPlayer 资源。首先判断 mPlayer 是否为 null，如果不为 null，则调用 stop 方法停止播放，接着调用 release 方法释放相关资源，最后将 mPlayer 置为 null，确保资源被正确回收，避免内存泄漏等问题。
+ */
+
+package net.micode.notes.ui;
+
+import android.app.Activity;
+import android.app.AlertDialog;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.content.DialogInterface.OnClickListener;
+import android.content.DialogInterface.OnDismissListener;
+import android.content.Intent;
+import android.media.AudioManager;
+import android.media.MediaPlayer;
+import android.media.RingtoneManager;
+import android.net.Uri;
+import android.os.Bundle;
+import android.os.PowerManager;
+import android.provider.Settings;
+import android.view.Window;
+import android.view.WindowManager;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.tool.DataUtils;
+
+import java.io.IOException;
+
+
+public class AlarmAlertActivity extends Activity implements OnClickListener, OnDismissListener {
+    private long mNoteId;
+    private String mSnippet;
+    private static final int SNIPPET_PREW_MAX_LEN = 60;
+    MediaPlayer mPlayer;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        requestWindowFeature(Window.FEATURE_NO_TITLE);
+
+        final Window win = getWindow();
+        win.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
+
+        if (!isScreenOn()) {
+            win.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
+                    | WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
+                    | WindowManager.LayoutParams.FLAG_ALLOW_LOCK_WHILE_SCREEN_ON
+                    | WindowManager.LayoutParams.FLAG_LAYOUT_INSET_DECOR);
+        }
+
+        Intent intent = getIntent();
+
+        try {
+            mNoteId = Long.valueOf(intent.getData().getPathSegments().get(1));
+            mSnippet = DataUtils.getSnippetById(this.getContentResolver(), mNoteId);
+            mSnippet = mSnippet.length() > SNIPPET_PREW_MAX_LEN ? mSnippet.substring(0,
+                    SNIPPET_PREW_MAX_LEN) + getResources().getString(R.string.notelist_string_info)
+                    : mSnippet;
+        } catch (IllegalArgumentException e) {
+            e.printStackTrace();
+            return;
+        }
+
+        mPlayer = new MediaPlayer();
+        if (DataUtils.visibleInNoteDatabase(getContentResolver(), mNoteId, Notes.TYPE_NOTE)) {
+            showActionDialog();
+            playAlarmSound();
+        } else {
+            finish();
+        }
+    }
+
+    private boolean isScreenOn() {
+        PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
+        return pm.isScreenOn();
+    }
+
+    private void playAlarmSound() {
+        Uri url = RingtoneManager.getActualDefaultRingtoneUri(this, RingtoneManager.TYPE_ALARM);
+
+        int silentModeStreams = Settings.System.getInt(getContentResolver(),
+                Settings.System.MODE_RINGER_STREAMS_AFFECTED, 0);
+
+        if ((silentModeStreams & (1 << AudioManager.STREAM_ALARM)) != 0) {
+            mPlayer.setAudioStreamType(silentModeStreams);
+        } else {
+            mPlayer.setAudioStreamType(AudioManager.STREAM_ALARM);
+        }
+        try {
+            mPlayer.setDataSource(this, url);
+            mPlayer.prepare();
+            mPlayer.setLooping(true);
+            mPlayer.start();
+        } catch (IllegalArgumentException e) {
+            // TODO Auto-generated catch block
+            e.printStackTrace();
+        } catch (SecurityException e) {
+            // TODO Auto-generated catch block
+            e.printStackTrace();
+        } catch (IllegalStateException e) {
+            // TODO Auto-generated catch block
+            e.printStackTrace();
+        } catch (IOException e) {
+            // TODO Auto-generated catch block
+            e.printStackTrace();
+        }
+    }
+
+    private void showActionDialog() {
+        AlertDialog.Builder dialog = new AlertDialog.Builder(this);
+        dialog.setTitle(R.string.app_name);
+        dialog.setMessage(mSnippet);
+        dialog.setPositiveButton(R.string.notealert_ok, this);
+        if (isScreenOn()) {
+            dialog.setNegativeButton(R.string.notealert_enter, this);
+        }
+        dialog.show().setOnDismissListener(this);
+    }
+
+    public void onClick(DialogInterface dialog, int which) {
+        switch (which) {
+            case DialogInterface.BUTTON_NEGATIVE:
+                Intent intent = new Intent(this, NoteEditActivity.class);
+                intent.setAction(Intent.ACTION_VIEW);
+                intent.putExtra(Intent.EXTRA_UID, mNoteId);
+                startActivity(intent);
+                break;
+            default:
+                break;
+        }
+    }
+
+    public void onDismiss(DialogInterface dialog) {
+        stopAlarmSound();
+        finish();
+    }
+
+    private void stopAlarmSound() {
+        if (mPlayer != null) {
+            mPlayer.stop();
+            mPlayer.release();
+            mPlayer = null;
+        }
+    }
+}

java/net/micode/notes/ui/AlarmInitReceiver.java

@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 当接收到系统广播时（在AlarmInitReceiver类的onReceive方法中处理广播接收逻辑），首先获取当前系统时间，然后从与笔记相关的内容提供者（通过Notes.CONTENT_NOTE_URI指定）中查询出提醒日期大于当前时间且类型为普通笔记类型的记录，查询结果只获取笔记的ID和提醒日期这两个字段。
+对于查询到的每条符合条件的笔记记录，程序会创建一个Intent，将当前笔记的ID附加到指定的Uri上并设置为该Intent的数据部分，接着创建一个对应的PendingIntent用于广播操作，最后获取系统的AlarmManager服务，设置一个基于实时时钟（RTC_WAKEUP类型）的闹钟提醒，当到达提醒日期时，系统会发送广播触发AlarmReceiver（在代码中Intent指定的目标广播接收者类）的相应逻辑，从而实现根据笔记的提醒设置来初始化闹钟提醒功能，确保在合适的时间提醒用户相关笔记的事项。
+
+ *onReceive 函数
+所属类：AlarmInitReceiver，它继承自 BroadcastReceiver，意味着这个类用于接收系统广播并处理相应逻辑。
+功能：
+首先获取当前的系统时间（以毫秒为单位，通过 System.currentTimeMillis 方法），将其存储在 currentDate 变量中，这个时间会用于后续的数据库查询条件判断。
+使用 context.getContentResolver().query 方法从内容提供者（此处应该是和笔记相关的数据存储，通过 Notes.CONTENT_NOTE_URI 指定查询的数据源）中查询数据。查询的字段通过 PROJECTION 数组指定，只获取笔记的 ID（NoteColumns.ID）和提醒日期（NoteColumns.ALERTED_DATE）这两个字段。查询的筛选条件是提醒日期大于当前日期（NoteColumns.ALERTED_DATE + ">?"）并且笔记类型为普通笔记类型（NoteColumns.TYPE + "=" + Notes.TYPE_NOTE），其中当前日期作为参数传入（通过 new String[] { String.valueOf(currentDate) }），排序规则为 null（即不指定排序）。
+接着判断查询得到的游标 c 是否为 null，如果不为 null，则进一步判断游标是否能移动到第一条记录（通过 moveToFirst 方法），若可以，进入循环（do-while 循环，通过 moveToNext 方法判断是否还有下一条记录来决定循环是否继续）。在循环内：
+获取当前记录对应的提醒日期（通过 c.getLong(COLUMN_ALERTED_DATE) 获取对应列的值）。
+创建一个新的 Intent，指定其目标广播接收者为 AlarmReceiver 类（意味着后续会将这个 Intent 作为广播发送给 AlarmReceiver 处理相关逻辑），并通过 ContentUris.withAppendedId 方法将当前笔记的 ID 附加到 Notes.CONTENT_NOTE_URI 上，设置为这个 Intent 的数据部分，用于传递具体是哪个笔记的相关信息。
+根据这个 Intent 创建一个 PendingIntent，它可以看作是一种延迟执行或者在特定条件下执行的 Intent，此处使用 PendingIntent.getBroadcast 方法，表明这是一个用于广播的 PendingIntent，并且设置请求码为 0 等相关参数。
+获取系统的 AlarmManager 服务（通过 context.getSystemService(Context.ALARM_SERVICE)），然后使用 set 方法设置一个闹钟提醒，闹钟类型为 RTC_WAKEUP（表示在指定的绝对时间唤醒设备来触发提醒，基于实时时钟），提醒时间为之前获取的 alertDate，触发的 PendingIntent 就是刚刚创建的那个，这样当到达指定提醒时间时，系统就会发送广播触发 AlarmReceiver 对应的逻辑。
+最后，如果游标 c 不为 null，在处理完所有符合条件的记录后，通过 c.close 方法关闭游标，释放相关资源，避免内存泄漏等问题。
+关于 PROJECTION 数组相关常量
+功能说明：
+PROJECTION 数组定义了查询数据库时要获取的字段列表，这里明确指定只获取笔记的 ID（对应 NoteColumns.ID）和提醒日期（对应 NoteColumns.ALERTED_DATE）这两个字段，用于后续在循环中获取相应数据来设置闹钟提醒等操作。
+COLUMN_ID 和 COLUMN_ALERTED_DATE 这两个常量分别定义了在查询结果游标中对应字段的索引位置，方便后续通过游标获取对应列的值，例如 c.getLong(COLUMN_ALERTED_DATE) 就是按照这个定义好的索引位置准确获取提醒日期字段的值，代码结构上更加清晰和便于维护，避免直接使用硬编码的索引数字。
+ */
+
+package net.micode.notes.ui;
+
+import android.app.AlarmManager;
+import android.app.PendingIntent;
+import android.content.BroadcastReceiver;
+import android.content.ContentUris;
+import android.content.Context;
+import android.content.Intent;
+import android.database.Cursor;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.NoteColumns;
+
+
+public class AlarmInitReceiver extends BroadcastReceiver {
+
+    private static final String [] PROJECTION = new String [] {
+        NoteColumns.ID,
+        NoteColumns.ALERTED_DATE
+    };
+
+    private static final int COLUMN_ID                = 0;
+    private static final int COLUMN_ALERTED_DATE      = 1;
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        long currentDate = System.currentTimeMillis();
+        Cursor c = context.getContentResolver().query(Notes.CONTENT_NOTE_URI,
+                PROJECTION,
+                NoteColumns.ALERTED_DATE + ">? AND " + NoteColumns.TYPE + "=" + Notes.TYPE_NOTE,
+                new String[] { String.valueOf(currentDate) },
+                null);
+
+        if (c != null) {
+            if (c.moveToFirst()) {
+                do {
+                    long alertDate = c.getLong(COLUMN_ALERTED_DATE);
+                    Intent sender = new Intent(context, AlarmReceiver.class);
+                    sender.setData(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, c.getLong(COLUMN_ID)));
+                    PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0, sender, 0);
+                    AlarmManager alermManager = (AlarmManager) context
+                            .getSystemService(Context.ALARM_SERVICE);
+                    alermManager.set(AlarmManager.RTC_WAKEUP, alertDate, pendingIntent);
+                } while (c.moveToNext());
+            }
+            c.close();
+        }
+    }
+}

java/net/micode/notes/ui/AlarmReceiver.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 程序定义了一个名为AlarmReceiver的广播接收者类，其主要功能是在接收到相应广播后，进行一系列操作来启动一个新的Activity（AlarmAlertActivity）。通过设置相关的Intent标志位以及指定目标Activity类，利用Context的startActivity方法来启动该Activity，整体在安卓系统的广播机制中起到了从接收到广播到触发对应界面显示的衔接作用，从而可以基于之前设置的闹钟提醒等相关广播触发逻辑，展示出提醒用户的具体界面（由AlarmAlertActivity负责呈现）。
+函数分析
+onReceive函数：
+所属类：AlarmReceiver，继承自BroadcastReceiver，专门用于处理接收到的广播消息。
+功能：
+首先，使用intent.setClass方法对传入的Intent进行设置，将其目标类指定为AlarmAlertActivity，也就是告诉系统，接下来要启动的是这个Activity，以此来确定具体要展示的界面内容。
+接着，通过intent.addFlags方法给Intent添加FLAG_ACTIVITY_NEW_TASK标志位，这个标志位的作用是让启动的Activity在新的任务栈中进行创建和运行，这对于广播接收者启动Activity的场景来说是很有必要的，确保Activity能正确启动并展示给用户，避免一些因任务栈相关问题导致的启动异常等情况。
+最后，调用context.startActivity方法，传入处理后的Intent，从而触发启动AlarmAlertActivity，完成从接收到广播到展示对应提醒界面的完整流程。
+ */
+
+package net.micode.notes.ui;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+
+public class AlarmReceiver extends BroadcastReceiver {
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        intent.setClass(context, AlarmAlertActivity.class);
+        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+        context.startActivity(intent);
+    }
+}

java/net/micode/notes/ui/DateTimePicker.java

@@ -0,0 +1,510 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了一个名为DateTimePicker的自定义视图类，用于实现一个方便用户选择日期和时间的交互组件。它基于安卓的相关时间处理类以及视图组件（如NumberPicker）构建而成，支持 24 小时制和 12 小时制（含 AM/PM 标识）的时间显示与选择，并且可以方便地获取和设置年、月、日、时、分等具体时间信息，同时提供了相应的监听器接口，当时间相关的值发生改变时能触发回调通知外部代码，整体旨在为安卓应用中涉及时间选择的场景提供一个可定制且功能较全面的 UI 组件。
+函数分析
+构造函数相关
+DateTimePicker(Context context)、DateTimePicker(Context context, long date)、DateTimePicker(Context context, long date, boolean is24HourView)：
+功能概述：这几个是重载的构造函数，用于创建DateTimePicker实例。它们根据传入参数的不同来初始化组件的不同状态。最基础的构造函数会以当前系统时间作为初始时间进行初始化，而带有日期参数的构造函数则按照传入的指定日期来初始化，带有额外布尔值参数的构造函数还可以指定是否采用 24 小时制来初始化时间显示模式等。
+具体细节：
+在构造函数内部，首先获取一个Calendar实例用于表示日期时间，标记正在初始化（mInitialising设为true），根据当前小时数判断是上午还是下午（确定mIsAm的值），然后通过inflate方法加载对应的布局文件（R.layout.datetime_picker）来构建视图的外观。
+接着获取布局中的各个NumberPicker组件（分别对应日期、小时、分钟、AM/PM），并为它们设置合适的最小值、最大值以及各自对应的OnValueChangeListener监听器，这些监听器会在对应NumberPicker的值发生改变时执行相应逻辑来更新整个时间状态以及触发对外的时间改变通知等。例如，mOnDateChangedListener用于处理日期选择改变时的逻辑，如更新日期、触发整体时间改变通知等。
+之后调用一系列update开头的函数（如updateDateControl、updateHourControl、updateAmPmControl）来初始化各个时间相关组件的显示内容和状态，按照传入的参数设置是否为 24 小时制（set24HourView方法调用），设置初始时间（通过setCurrentDate相关方法），设置组件的启用状态（调用setEnabled方法），最后将mInitialising设为false表示初始化完成。
+时间获取相关函数
+getCurrentDateInTimeMillis()：
+功能：返回当前通过DateTimePicker组件所表示的日期时间对应的毫秒数，通过获取内部Calendar实例（mDate）的时间毫秒值来实现，外部代码可以利用这个值来进一步存储或者传递该时间信息等。
+getCurrentYear()、getCurrentMonth()、getCurrentDay()、getCurrentHourOfDay()、getCurrentMinute()：
+功能：这些函数分别用于获取当前在DateTimePicker组件中所表示时间的年、月、日、24 小时制的小时数、分钟数，都是通过调用内部Calendar实例（mDate）的对应get方法（如Calendar.YEAR、Calendar.MONTH等）来获取相应的值，方便外部代码获取具体的时间字段信息。
+时间设置相关函数
+setCurrentDate(long date)、setCurrentDate(int year, int month, int dayOfMonth, int hourOfDay, int minute)：
+功能：前者接收一个表示日期时间的毫秒数参数，后者接收年、月、日、小时、分钟的具体整数值参数，它们最终都是调用内部的一系列setCurrent开头的函数（如setCurrentYear、setCurrentMonth等）来分别设置对应的时间字段，在设置过程中会进行一些合理性判断（如判断是否正在初始化以及当前值与传入值是否相同等情况来决定是否执行更新操作），并且更新相关的时间显示组件以及触发时间改变的通知（通过onDateTimeChanged方法）。
+setCurrentYear(int year)、setCurrentMonth(int month)、setCurrentDay(int dayOfMonth)、setCurrentHour(int hourOfDay)、setCurrentMinute(int minute)：
+功能：这些函数分别用于单独设置时间中的年、月、日、小时、分钟字段的值，同样在设置时会进行一些前置判断（如是否正在初始化以及当前值与传入值对比等），然后通过mDate（Calendar实例）的对应set方法来更新内部时间状态，并且会更新相应的时间显示组件以及触发时间改变的通知，确保整个DateTimePicker组件的时间状态和显示能保持一致并且外部能得知时间的改变情况。
+时间显示模式相关函数
+is24HourView()：
+功能：返回一个布尔值，用于表示当前DateTimePicker组件是否处于 24 小时制显示时间的模式，通过查看内部的mIs24HourView变量的值来确定，外部代码可以利用这个函数来知晓当前的时间显示格式情况。
+set24HourView(boolean is24HourView)：
+功能：用于设置DateTimePicker组件的时间显示模式，根据传入的布尔值参数来决定是否切换为 24 小时制或 12 小时制（含 AM/PM 显示）。在切换过程中，会调整AmPmSpinner组件的可见性，更新小时选择组件（HourSpinner）的取值范围，重新设置当前小时数并更新 AM/PM 显示控制等相关操作，以确保整个组件的显示与设置的时间显示模式相匹配。
+ */
+
+package net.micode.notes.ui;
+
+import java.text.DateFormatSymbols;
+import java.util.Calendar;
+
+import net.micode.notes.R;
+
+
+import android.content.Context;
+import android.text.format.DateFormat;
+import android.view.View;
+import android.widget.FrameLayout;
+import android.widget.NumberPicker;
+
+public class DateTimePicker extends FrameLayout {
+
+    private static final boolean DEFAULT_ENABLE_STATE = true;
+
+    private static final int HOURS_IN_HALF_DAY = 12;
+    private static final int HOURS_IN_ALL_DAY = 24;
+    private static final int DAYS_IN_ALL_WEEK = 7;
+    private static final int DATE_SPINNER_MIN_VAL = 0;
+    private static final int DATE_SPINNER_MAX_VAL = DAYS_IN_ALL_WEEK - 1;
+    private static final int HOUR_SPINNER_MIN_VAL_24_HOUR_VIEW = 0;
+    private static final int HOUR_SPINNER_MAX_VAL_24_HOUR_VIEW = 23;
+    private static final int HOUR_SPINNER_MIN_VAL_12_HOUR_VIEW = 1;
+    private static final int HOUR_SPINNER_MAX_VAL_12_HOUR_VIEW = 12;
+    private static final int MINUT_SPINNER_MIN_VAL = 0;
+    private static final int MINUT_SPINNER_MAX_VAL = 59;
+    private static final int AMPM_SPINNER_MIN_VAL = 0;
+    private static final int AMPM_SPINNER_MAX_VAL = 1;
+
+    private final NumberPicker mDateSpinner;
+    private final NumberPicker mHourSpinner;
+    private final NumberPicker mMinuteSpinner;
+    private final NumberPicker mAmPmSpinner;
+    private Calendar mDate;
+
+    private String[] mDateDisplayValues = new String[DAYS_IN_ALL_WEEK];
+
+    private boolean mIsAm;
+
+    private boolean mIs24HourView;
+
+    private boolean mIsEnabled = DEFAULT_ENABLE_STATE;
+
+    private boolean mInitialising;
+
+    private OnDateTimeChangedListener mOnDateTimeChangedListener;
+
+    private NumberPicker.OnValueChangeListener mOnDateChangedListener = new NumberPicker.OnValueChangeListener() {
+        @Override
+        public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
+            mDate.add(Calendar.DAY_OF_YEAR, newVal - oldVal);
+            updateDateControl();
+            onDateTimeChanged();
+        }
+    };
+
+    private NumberPicker.OnValueChangeListener mOnHourChangedListener = new NumberPicker.OnValueChangeListener() {
+        @Override
+        public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
+            boolean isDateChanged = false;
+            Calendar cal = Calendar.getInstance();
+            if (!mIs24HourView) {
+                if (!mIsAm && oldVal == HOURS_IN_HALF_DAY - 1 && newVal == HOURS_IN_HALF_DAY) {
+                    cal.setTimeInMillis(mDate.getTimeInMillis());
+                    cal.add(Calendar.DAY_OF_YEAR, 1);
+                    isDateChanged = true;
+                } else if (mIsAm && oldVal == HOURS_IN_HALF_DAY && newVal == HOURS_IN_HALF_DAY - 1) {
+                    cal.setTimeInMillis(mDate.getTimeInMillis());
+                    cal.add(Calendar.DAY_OF_YEAR, -1);
+                    isDateChanged = true;
+                }
+                if (oldVal == HOURS_IN_HALF_DAY - 1 && newVal == HOURS_IN_HALF_DAY ||
+                        oldVal == HOURS_IN_HALF_DAY && newVal == HOURS_IN_HALF_DAY - 1) {
+                    mIsAm = !mIsAm;
+                    updateAmPmControl();
+                }
+            } else {
+                if (oldVal == HOURS_IN_ALL_DAY - 1 && newVal == 0) {
+                    cal.setTimeInMillis(mDate.getTimeInMillis());
+                    cal.add(Calendar.DAY_OF_YEAR, 1);
+                    isDateChanged = true;
+                } else if (oldVal == 0 && newVal == HOURS_IN_ALL_DAY - 1) {
+                    cal.setTimeInMillis(mDate.getTimeInMillis());
+                    cal.add(Calendar.DAY_OF_YEAR, -1);
+                    isDateChanged = true;
+                }
+            }
+            int newHour = mHourSpinner.getValue() % HOURS_IN_HALF_DAY + (mIsAm ? 0 : HOURS_IN_HALF_DAY);
+            mDate.set(Calendar.HOUR_OF_DAY, newHour);
+            onDateTimeChanged();
+            if (isDateChanged) {
+                setCurrentYear(cal.get(Calendar.YEAR));
+                setCurrentMonth(cal.get(Calendar.MONTH));
+                setCurrentDay(cal.get(Calendar.DAY_OF_MONTH));
+            }
+        }
+    };
+
+    private NumberPicker.OnValueChangeListener mOnMinuteChangedListener = new NumberPicker.OnValueChangeListener() {
+        @Override
+        public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
+            int minValue = mMinuteSpinner.getMinValue();
+            int maxValue = mMinuteSpinner.getMaxValue();
+            int offset = 0;
+            if (oldVal == maxValue && newVal == minValue) {
+                offset += 1;
+            } else if (oldVal == minValue && newVal == maxValue) {
+                offset -= 1;
+            }
+            if (offset != 0) {
+                mDate.add(Calendar.HOUR_OF_DAY, offset);
+                mHourSpinner.setValue(getCurrentHour());
+                updateDateControl();
+                int newHour = getCurrentHourOfDay();
+                if (newHour >= HOURS_IN_HALF_DAY) {
+                    mIsAm = false;
+                    updateAmPmControl();
+                } else {
+                    mIsAm = true;
+                    updateAmPmControl();
+                }
+            }
+            mDate.set(Calendar.MINUTE, newVal);
+            onDateTimeChanged();
+        }
+    };
+
+    private NumberPicker.OnValueChangeListener mOnAmPmChangedListener = new NumberPicker.OnValueChangeListener() {
+        @Override
+        public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
+            mIsAm = !mIsAm;
+            if (mIsAm) {
+                mDate.add(Calendar.HOUR_OF_DAY, -HOURS_IN_HALF_DAY);
+            } else {
+                mDate.add(Calendar.HOUR_OF_DAY, HOURS_IN_HALF_DAY);
+            }
+            updateAmPmControl();
+            onDateTimeChanged();
+        }
+    };
+
+    public interface OnDateTimeChangedListener {
+        void onDateTimeChanged(DateTimePicker view, int year, int month,
+                int dayOfMonth, int hourOfDay, int minute);
+    }
+
+    public DateTimePicker(Context context) {
+        this(context, System.currentTimeMillis());
+    }
+
+    public DateTimePicker(Context context, long date) {
+        this(context, date, DateFormat.is24HourFormat(context));
+    }
+
+    public DateTimePicker(Context context, long date, boolean is24HourView) {
+        super(context);
+        mDate = Calendar.getInstance();
+        mInitialising = true;
+        mIsAm = getCurrentHourOfDay() >= HOURS_IN_HALF_DAY;
+        inflate(context, R.layout.datetime_picker, this);
+
+        mDateSpinner = (NumberPicker) findViewById(R.id.date);
+        mDateSpinner.setMinValue(DATE_SPINNER_MIN_VAL);
+        mDateSpinner.setMaxValue(DATE_SPINNER_MAX_VAL);
+        mDateSpinner.setOnValueChangedListener(mOnDateChangedListener);
+
+        mHourSpinner = (NumberPicker) findViewById(R.id.hour);
+        mHourSpinner.setOnValueChangedListener(mOnHourChangedListener);
+        mMinuteSpinner =  (NumberPicker) findViewById(R.id.minute);
+        mMinuteSpinner.setMinValue(MINUT_SPINNER_MIN_VAL);
+        mMinuteSpinner.setMaxValue(MINUT_SPINNER_MAX_VAL);
+        mMinuteSpinner.setOnLongPressUpdateInterval(100);
+        mMinuteSpinner.setOnValueChangedListener(mOnMinuteChangedListener);
+
+        String[] stringsForAmPm = new DateFormatSymbols().getAmPmStrings();
+        mAmPmSpinner = (NumberPicker) findViewById(R.id.amPm);
+        mAmPmSpinner.setMinValue(AMPM_SPINNER_MIN_VAL);
+        mAmPmSpinner.setMaxValue(AMPM_SPINNER_MAX_VAL);
+        mAmPmSpinner.setDisplayedValues(stringsForAmPm);
+        mAmPmSpinner.setOnValueChangedListener(mOnAmPmChangedListener);
+
+        // update controls to initial state
+        updateDateControl();
+        updateHourControl();
+        updateAmPmControl();
+
+        set24HourView(is24HourView);
+
+        // set to current time
+        setCurrentDate(date);
+
+        setEnabled(isEnabled());
+
+        // set the content descriptions
+        mInitialising = false;
+    }
+
+    @Override
+    public void setEnabled(boolean enabled) {
+        if (mIsEnabled == enabled) {
+            return;
+        }
+        super.setEnabled(enabled);
+        mDateSpinner.setEnabled(enabled);
+        mMinuteSpinner.setEnabled(enabled);
+        mHourSpinner.setEnabled(enabled);
+        mAmPmSpinner.setEnabled(enabled);
+        mIsEnabled = enabled;
+    }
+
+    @Override
+    public boolean isEnabled() {
+        return mIsEnabled;
+    }
+
+    /**
+     * Get the current date in millis
+     *
+     * @return the current date in millis
+     */
+    public long getCurrentDateInTimeMillis() {
+        return mDate.getTimeInMillis();
+    }
+
+    /**
+     * Set the current date
+     *
+     * @param date The current date in millis
+     */
+    public void setCurrentDate(long date) {
+        Calendar cal = Calendar.getInstance();
+        cal.setTimeInMillis(date);
+        setCurrentDate(cal.get(Calendar.YEAR), cal.get(Calendar.MONTH), cal.get(Calendar.DAY_OF_MONTH),
+                cal.get(Calendar.HOUR_OF_DAY), cal.get(Calendar.MINUTE));
+    }
+
+    /**
+     * Set the current date
+     *
+     * @param year The current year
+     * @param month The current month
+     * @param dayOfMonth The current dayOfMonth
+     * @param hourOfDay The current hourOfDay
+     * @param minute The current minute
+     */
+    public void setCurrentDate(int year, int month,
+            int dayOfMonth, int hourOfDay, int minute) {
+        setCurrentYear(year);
+        setCurrentMonth(month);
+        setCurrentDay(dayOfMonth);
+        setCurrentHour(hourOfDay);
+        setCurrentMinute(minute);
+    }
+
+    /**
+     * Get current year
+     *
+     * @return The current year
+     */
+    public int getCurrentYear() {
+        return mDate.get(Calendar.YEAR);
+    }
+
+    /**
+     * Set current year
+     *
+     * @param year The current year
+     */
+    public void setCurrentYear(int year) {
+        if (!mInitialising && year == getCurrentYear()) {
+            return;
+        }
+        mDate.set(Calendar.YEAR, year);
+        updateDateControl();
+        onDateTimeChanged();
+    }
+
+    /**
+     * Get current month in the year
+     *
+     * @return The current month in the year
+     */
+    public int getCurrentMonth() {
+        return mDate.get(Calendar.MONTH);
+    }
+
+    /**
+     * Set current month in the year
+     *
+     * @param month The month in the year
+     */
+    public void setCurrentMonth(int month) {
+        if (!mInitialising && month == getCurrentMonth()) {
+            return;
+        }
+        mDate.set(Calendar.MONTH, month);
+        updateDateControl();
+        onDateTimeChanged();
+    }
+
+    /**
+     * Get current day of the month
+     *
+     * @return The day of the month
+     */
+    public int getCurrentDay() {
+        return mDate.get(Calendar.DAY_OF_MONTH);
+    }
+
+    /**
+     * Set current day of the month
+     *
+     * @param dayOfMonth The day of the month
+     */
+    public void setCurrentDay(int dayOfMonth) {
+        if (!mInitialising && dayOfMonth == getCurrentDay()) {
+            return;
+        }
+        mDate.set(Calendar.DAY_OF_MONTH, dayOfMonth);
+        updateDateControl();
+        onDateTimeChanged();
+    }
+
+    /**
+     * Get current hour in 24 hour mode, in the range (0~23)
+     * @return The current hour in 24 hour mode
+     */
+    public int getCurrentHourOfDay() {
+        return mDate.get(Calendar.HOUR_OF_DAY);
+    }
+
+    private int getCurrentHour() {
+        if (mIs24HourView){
+            return getCurrentHourOfDay();
+        } else {
+            int hour = getCurrentHourOfDay();
+            if (hour > HOURS_IN_HALF_DAY) {
+                return hour - HOURS_IN_HALF_DAY;
+            } else {
+                return hour == 0 ? HOURS_IN_HALF_DAY : hour;
+            }
+        }
+    }
+
+    /**
+     * Set current hour in 24 hour mode, in the range (0~23)
+     *
+     * @param hourOfDay
+     */
+    public void setCurrentHour(int hourOfDay) {
+        if (!mInitialising && hourOfDay == getCurrentHourOfDay()) {
+            return;
+        }
+        mDate.set(Calendar.HOUR_OF_DAY, hourOfDay);
+        if (!mIs24HourView) {
+            if (hourOfDay >= HOURS_IN_HALF_DAY) {
+                mIsAm = false;
+                if (hourOfDay > HOURS_IN_HALF_DAY) {
+                    hourOfDay -= HOURS_IN_HALF_DAY;
+                }
+            } else {
+                mIsAm = true;
+                if (hourOfDay == 0) {
+                    hourOfDay = HOURS_IN_HALF_DAY;
+                }
+            }
+            updateAmPmControl();
+        }
+        mHourSpinner.setValue(hourOfDay);
+        onDateTimeChanged();
+    }
+
+    /**
+     * Get currentMinute
+     *
+     * @return The Current Minute
+     */
+    public int getCurrentMinute() {
+        return mDate.get(Calendar.MINUTE);
+    }
+
+    /**
+     * Set current minute
+     */
+    public void setCurrentMinute(int minute) {
+        if (!mInitialising && minute == getCurrentMinute()) {
+            return;
+        }
+        mMinuteSpinner.setValue(minute);
+        mDate.set(Calendar.MINUTE, minute);
+        onDateTimeChanged();
+    }
+
+    /**
+     * @return true if this is in 24 hour view else false.
+     */
+    public boolean is24HourView () {
+        return mIs24HourView;
+    }
+
+    /**
+     * Set whether in 24 hour or AM/PM mode.
+     *
+     * @param is24HourView True for 24 hour mode. False for AM/PM mode.
+     */
+    public void set24HourView(boolean is24HourView) {
+        if (mIs24HourView == is24HourView) {
+            return;
+        }
+        mIs24HourView = is24HourView;
+        mAmPmSpinner.setVisibility(is24HourView ? View.GONE : View.VISIBLE);
+        int hour = getCurrentHourOfDay();
+        updateHourControl();
+        setCurrentHour(hour);
+        updateAmPmControl();
+    }
+
+    private void updateDateControl() {
+        Calendar cal = Calendar.getInstance();
+        cal.setTimeInMillis(mDate.getTimeInMillis());
+        cal.add(Calendar.DAY_OF_YEAR, -DAYS_IN_ALL_WEEK / 2 - 1);
+        mDateSpinner.setDisplayedValues(null);
+        for (int i = 0; i < DAYS_IN_ALL_WEEK; ++i) {
+            cal.add(Calendar.DAY_OF_YEAR, 1);
+            mDateDisplayValues[i] = (String) DateFormat.format("MM.dd EEEE", cal);
+        }
+        mDateSpinner.setDisplayedValues(mDateDisplayValues);
+        mDateSpinner.setValue(DAYS_IN_ALL_WEEK / 2);
+        mDateSpinner.invalidate();
+    }
+
+    private void updateAmPmControl() {
+        if (mIs24HourView) {
+            mAmPmSpinner.setVisibility(View.GONE);
+        } else {
+            int index = mIsAm ? Calendar.AM : Calendar.PM;
+            mAmPmSpinner.setValue(index);
+            mAmPmSpinner.setVisibility(View.VISIBLE);
+        }
+    }
+
+    private void updateHourControl() {
+        if (mIs24HourView) {
+            mHourSpinner.setMinValue(HOUR_SPINNER_MIN_VAL_24_HOUR_VIEW);
+            mHourSpinner.setMaxValue(HOUR_SPINNER_MAX_VAL_24_HOUR_VIEW);
+        } else {
+            mHourSpinner.setMinValue(HOUR_SPINNER_MIN_VAL_12_HOUR_VIEW);
+            mHourSpinner.setMaxValue(HOUR_SPINNER_MAX_VAL_12_HOUR_VIEW);
+        }
+    }
+
+    /**
+     * Set the callback that indicates the 'Set' button has been pressed.
+     * @param callback the callback, if null will do nothing
+     */
+    public void setOnDateTimeChangedListener(OnDateTimeChangedListener callback) {
+        mOnDateTimeChangedListener = callback;
+    }
+
+    private void onDateTimeChanged() {
+        if (mOnDateTimeChangedListener != null) {
+            mOnDateTimeChangedListener.onDateTimeChanged(this, getCurrentYear(),
+                    getCurrentMonth(), getCurrentDay(), getCurrentHourOfDay(), getCurrentMinute());
+        }
+    }
+}

java/net/micode/notes/ui/DateTimePickerDialog.java

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.ui;
+
+import java.util.Calendar;
+
+import net.micode.notes.R;
+import net.micode.notes.ui.DateTimePicker;
+import net.micode.notes.ui.DateTimePicker.OnDateTimeChangedListener;
+
+import android.app.AlertDialog;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.content.DialogInterface.OnClickListener;
+import android.text.format.DateFormat;
+import android.text.format.DateUtils;
+
+public class DateTimePickerDialog extends AlertDialog implements OnClickListener {
+
+    private Calendar mDate = Calendar.getInstance();
+    private boolean mIs24HourView;
+    private OnDateTimeSetListener mOnDateTimeSetListener;
+    private DateTimePicker mDateTimePicker;
+
+    public interface OnDateTimeSetListener {
+        void OnDateTimeSet(AlertDialog dialog, long date);
+    }
+
+    public DateTimePickerDialog(Context context, long date) {
+        super(context);
+        mDateTimePicker = new DateTimePicker(context);
+        setView(mDateTimePicker);
+        mDateTimePicker.setOnDateTimeChangedListener(new OnDateTimeChangedListener() {
+            public void onDateTimeChanged(DateTimePicker view, int year, int month,
+                    int dayOfMonth, int hourOfDay, int minute) {
+                mDate.set(Calendar.YEAR, year);
+                mDate.set(Calendar.MONTH, month);
+                mDate.set(Calendar.DAY_OF_MONTH, dayOfMonth);
+                mDate.set(Calendar.HOUR_OF_DAY, hourOfDay);
+                mDate.set(Calendar.MINUTE, minute);
+                updateTitle(mDate.getTimeInMillis());
+            }
+        });
+        mDate.setTimeInMillis(date);
+        mDate.set(Calendar.SECOND, 0);
+        mDateTimePicker.setCurrentDate(mDate.getTimeInMillis());
+        setButton(context.getString(R.string.datetime_dialog_ok), this);
+        setButton2(context.getString(R.string.datetime_dialog_cancel), (OnClickListener)null);
+        set24HourView(DateFormat.is24HourFormat(this.getContext()));
+        updateTitle(mDate.getTimeInMillis());
+    }
+
+    public void set24HourView(boolean is24HourView) {
+        mIs24HourView = is24HourView;
+    }
+
+    public void setOnDateTimeSetListener(OnDateTimeSetListener callBack) {
+        mOnDateTimeSetListener = callBack;
+    }
+
+    private void updateTitle(long date) {
+        int flag =
+            DateUtils.FORMAT_SHOW_YEAR |
+            DateUtils.FORMAT_SHOW_DATE |
+            DateUtils.FORMAT_SHOW_TIME;
+        flag |= mIs24HourView ? DateUtils.FORMAT_24HOUR : DateUtils.FORMAT_24HOUR;
+        setTitle(DateUtils.formatDateTime(this.getContext(), date, flag));
+    }
+
+    public void onClick(DialogInterface arg0, int arg1) {
+        if (mOnDateTimeSetListener != null) {
+            mOnDateTimeSetListener.OnDateTimeSet(this, mDate.getTimeInMillis());
+        }
+    }
+
+}

java/net/micode/notes/ui/DropdownMenu.java

@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了一个名为DropdownMenu的类，其主要功能是创建一个带有下拉菜单功能的组件。它基于安卓系统中的Button和PopupMenu来实现，将Button作为触发下拉菜单显示的入口，通过设置相关的监听器、加载菜单资源等操作，方便在安卓应用界面中构建出一个能展示多种操作选项（通过下拉菜单形式呈现）的交互组件，并且提供了查找菜单项、设置按钮标题等实用的方法，增强了该组件在实际使用中的灵活性和可定制性。
+函数分析
+构造函数
+DropdownMenu(Context context, Button button, int menuId)：
+所属类：DropdownMenu
+功能：
+首先接收传入的Context（用于获取系统资源等操作）、Button（作为触发下拉菜单显示的按钮控件）以及menuId（用于指定要加载的菜单资源的ID）这三个参数。
+将传入的Button实例赋值给类内部的mButton变量，并通过setBackgroundResource方法为其设置背景资源（这里使用R.drawable.dropdown_icon指定的图标资源，应该是一个代表下拉箭头之类的图标，用于在视觉上提示用户该按钮可展开下拉菜单）。
+创建一个PopupMenu实例，将传入的Context和Button作为参数传入，使其与按钮关联起来，方便后续基于按钮位置来显示下拉菜单，然后获取这个PopupMenu的Menu对象并赋值给mMenu变量，用于后续操作菜单中的具体菜单项等。
+通过getMenuInflater方法获取菜单填充器，并调用inflate方法按照传入的menuId将对应的菜单资源加载到mMenu中，完成菜单内容的初始化。
+最后为mButton设置点击监听器，在监听器的onClick方法中，当按钮被点击时，调用mPopupMenu.show方法来显示关联的下拉菜单，实现点击按钮弹出下拉菜单的核心功能。
+设置监听器相关函数
+setOnDropdownMenuItemClickListener(OnMenuItemClickListener listener)：
+所属类：DropdownMenu
+功能：接收一个实现了OnMenuItemClickListener接口的监听器对象作为参数，用于设置下拉菜单中菜单项被点击时的监听器。在函数内部，先判断mPopupMenu是否为null（避免空指针异常），如果不为null，则通过mPopupMenu.setOnMenuItemClickListener方法将传入的监听器设置给PopupMenu，这样当用户点击下拉菜单中的某个菜单项时，对应的监听器中的回调方法就会被触发，外部代码可以在回调方法中编写处理具体菜单项点击逻辑的代码，例如执行不同的操作、跳转到不同的界面等。
+查找菜单项函数
+findItem(int id)：
+所属类：DropdownMenu
+功能：接收一个表示菜单项ID的整数参数，通过调用mMenu.findItem方法在内部的Menu对象（之前在构造函数中加载了菜单资源的那个Menu）中查找对应的菜单项，返回找到的MenuItem对象。外部代码可以利用这个函数来获取特定ID的菜单项，进而对其进行一些操作，比如获取菜单项的文本、设置菜单项是否可用等，方便根据具体的业务需求对菜单项进行定制化处理。
+设置标题函数
+setTitle(CharSequence title)：
+所属类：DropdownMenu
+功能：接收一个CharSequence类型（通常可以是字符串等文本内容）的参数，用于设置关联的Button的文本标题。在函数内部，直接通过mButton.setText方法将传入的标题文本设置给按钮，改变按钮上显示的文字内容，从视觉上为用户提供更明确的提示信息，比如可以根据当前菜单的功能或者所在的页面内容等设置合适的按钮标题，增强界面的可读性和易用性。
+ */
+
+package net.micode.notes.ui;
+
+import android.content.Context;
+import android.view.Menu;
+import android.view.MenuItem;
+import android.view.View;
+import android.view.View.OnClickListener;
+import android.widget.Button;
+import android.widget.PopupMenu;
+import android.widget.PopupMenu.OnMenuItemClickListener;
+
+import net.micode.notes.R;
+
+public class DropdownMenu {
+    private Button mButton;
+    private PopupMenu mPopupMenu;
+    private Menu mMenu;
+
+    public DropdownMenu(Context context, Button button, int menuId) {
+        mButton = button;
+        mButton.setBackgroundResource(R.drawable.dropdown_icon);
+        mPopupMenu = new PopupMenu(context, mButton);
+        mMenu = mPopupMenu.getMenu();
+        mPopupMenu.getMenuInflater().inflate(menuId, mMenu);
+        mButton.setOnClickListener(new OnClickListener() {
+            public void onClick(View v) {
+                mPopupMenu.show();
+            }
+        });
+    }
+
+    public void setOnDropdownMenuItemClickListener(OnMenuItemClickListener listener) {
+        if (mPopupMenu != null) {
+            mPopupMenu.setOnMenuItemClickListener(listener);
+        }
+    }
+
+    public MenuItem findItem(int id) {
+        return mMenu.findItem(id);
+    }
+
+    public void setTitle(CharSequence title) {
+        mButton.setText(title);
+    }
+}

java/net/micode/notes/ui/FoldersListAdapter.java

@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了一个名为FoldersListAdapter的类，它继承自CursorAdapter，主要用于在安卓应用中对数据库查询结果（以Cursor形式体现）进行适配，以便在列表等视图组件中展示相应的数据。它针对特定的笔记相关数据结构（从代码中的引用可推测涉及笔记文件夹相关信息），将查询到的包含文件夹ID和名称片段（SNIPPET）的数据，通过自定义的视图逻辑展示出来，同时提供了获取指定位置文件夹名称的方法，方便在界面交互过程中获取和展示文件夹相关的信息。
+函数分析
+构造函数
+FoldersListAdapter(Context context, Cursor c)：
+所属类：FoldersListAdapter
+功能：这是类的构造函数，接收Context（用于获取系统资源等操作）和Cursor（包含了从数据库查询出来的数据）这两个参数，调用父类（CursorAdapter）的构造函数并传入这两个参数，完成基础的初始化工作，确保后续可以基于这个Cursor中的数据来进行视图适配等相关操作。不过目前构造函数内部暂时没有其他自定义的额外初始化逻辑（代码中 TODO Auto-generated constructor stub 提示可能后续还有待完善的地方）。
+视图创建相关函数
+newView(Context context, Cursor cursor, ViewGroup parent)：
+所属类：FoldersListAdapter
+功能：重写了父类CursorAdapter的newView方法，用于创建一个新的视图对象来展示Cursor中的每一条数据记录。在这个方法中，它创建并返回了一个FolderListItem类的实例，这个FolderListItem类是内部定义的一个继承自LinearLayout的自定义视图类，意味着每一条数据记录都会通过这个自定义的线性布局样式的视图来展示，后续可以在这个自定义视图中进行具体的数据绑定和展示相关操作。
+视图数据绑定函数
+bindView(View view, Context context, Cursor cursor)：
+所属类：FoldersListAdapter
+功能：重写了父类CursorAdapter的bindView方法，用于将Cursor中的数据绑定到对应的视图上进行展示。首先判断传入的视图是否是FolderListItem类型，如果是，则从Cursor中获取相应的数据来确定文件夹名称。这里有个特殊判断，如果当前记录对应的文件夹ID是根文件夹的ID（通过 Notes.ID_ROOT_FOLDER 判断），则使用 getString 方法获取一个特定的资源字符串（R.string.menu_move_parent_folder）作为文件夹名称，否则直接获取Cursor中对应列（通过 NAME_COLUMN 索引）的字符串作为文件夹名称，最后调用 ((FolderListItem) view).bind(folderName) 将获取到的文件夹名称传递给 FolderListItem 实例的 bind 方法，在该方法中会将名称设置到对应的 TextView 组件上进行展示。
+获取文件夹名称函数
+getFolderName(Context context, int position)：
+所属类：FoldersListAdapter
+功能：用于获取指定位置的文件夹名称。它先通过 getItem 方法（继承自 CursorAdapter）获取对应位置的 Cursor 对象，然后同样按照之前在 bindView 方法中类似的逻辑，根据文件夹 ID 是否为根文件夹 ID 来确定返回的文件夹名称，如果是根文件夹就获取特定资源字符串作为名称，否则获取 Cursor 中对应列的字符串作为名称，方便外部代码在需要知晓特定位置文件夹名称的情况下进行调用。
+自定义视图类相关
+FolderListItem 内部类：
+所属类：FoldersListAdapter（作为其内部类存在）
+功能：
+构造函数方面，它继承自 LinearLayout，在构造函数中调用父类构造函数传入 Context，然后通过 inflate 方法加载一个名为 R.layout.folder_list_item 的布局文件到自身，这个布局文件应该定义了展示文件夹名称的具体视图样式，接着通过 findViewById 方法获取布局中的 TextView 组件（mName），用于后续设置和展示文件夹名称。
+bind 方法方面，接收一个字符串参数（文件夹名称），并通过 mName.setText(name) 将传入的名称设置到对应的 TextView 组件上，从而实现将数据展示在视图中的功能，完成视图与数据的绑定操作。
+ */
+
+package net.micode.notes.ui;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.CursorAdapter;
+import android.widget.LinearLayout;
+import android.widget.TextView;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.NoteColumns;
+
+
+public class FoldersListAdapter extends CursorAdapter {
+    public static final String [] PROJECTION = {
+        NoteColumns.ID,
+        NoteColumns.SNIPPET
+    };
+
+    public static final int ID_COLUMN   = 0;
+    public static final int NAME_COLUMN = 1;
+
+    public FoldersListAdapter(Context context, Cursor c) {
+        super(context, c);
+        // TODO Auto-generated constructor stub
+    }
+
+    @Override
+    public View newView(Context context, Cursor cursor, ViewGroup parent) {
+        return new FolderListItem(context);
+    }
+
+    @Override
+    public void bindView(View view, Context context, Cursor cursor) {
+        if (view instanceof FolderListItem) {
+            String folderName = (cursor.getLong(ID_COLUMN) == Notes.ID_ROOT_FOLDER) ? context
+                    .getString(R.string.menu_move_parent_folder) : cursor.getString(NAME_COLUMN);
+            ((FolderListItem) view).bind(folderName);
+        }
+    }
+
+    public String getFolderName(Context context, int position) {
+        Cursor cursor = (Cursor) getItem(position);
+        return (cursor.getLong(ID_COLUMN) == Notes.ID_ROOT_FOLDER) ? context
+                .getString(R.string.menu_move_parent_folder) : cursor.getString(NAME_COLUMN);
+    }
+
+    private class FolderListItem extends LinearLayout {
+        private TextView mName;
+
+        public FolderListItem(Context context) {
+            super(context);
+            inflate(context, R.layout.folder_list_item, this);
+            mName = (TextView) findViewById(R.id.tv_folder_name);
+        }
+
+        public void bind(String name) {
+            mName.setText(name);
+        }
+    }
+
+}

java/net/micode/notes/ui/NoteEditActivity.java

@@ -0,0 +1,873 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.ui;
+
+import android.app.Activity;
+import android.app.AlarmManager;
+import android.app.AlertDialog;
+import android.app.PendingIntent;
+import android.app.SearchManager;
+import android.appwidget.AppWidgetManager;
+import android.content.ContentUris;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.content.SharedPreferences;
+import android.graphics.Paint;
+import android.os.Bundle;
+import android.preference.PreferenceManager;
+import android.text.Spannable;
+import android.text.SpannableString;
+import android.text.TextUtils;
+import android.text.format.DateUtils;
+import android.text.style.BackgroundColorSpan;
+import android.util.Log;
+import android.view.LayoutInflater;
+import android.view.Menu;
+import android.view.MenuItem;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.View.OnClickListener;
+import android.view.WindowManager;
+import android.widget.CheckBox;
+import android.widget.CompoundButton;
+import android.widget.CompoundButton.OnCheckedChangeListener;
+import android.widget.EditText;
+import android.widget.ImageView;
+import android.widget.LinearLayout;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.TextNote;
+import net.micode.notes.model.WorkingNote;
+import net.micode.notes.model.WorkingNote.NoteSettingChangedListener;
+import net.micode.notes.tool.DataUtils;
+import net.micode.notes.tool.ResourceParser;
+import net.micode.notes.tool.ResourceParser.TextAppearanceResources;
+import net.micode.notes.ui.DateTimePickerDialog.OnDateTimeSetListener;
+import net.micode.notes.ui.NoteEditText.OnTextViewChangeListener;
+import net.micode.notes.widget.NoteWidgetProvider_2x;
+import net.micode.notes.widget.NoteWidgetProvider_4x;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+
+public class NoteEditActivity extends Activity implements OnClickListener,
+        NoteSettingChangedListener, OnTextViewChangeListener {
+    private class HeadViewHolder {
+        public TextView tvModified;
+
+        public ImageView ivAlertIcon;
+
+        public TextView tvAlertDate;
+
+        public ImageView ibSetBgColor;
+    }
+
+    private static final Map<Integer, Integer> sBgSelectorBtnsMap = new HashMap<Integer, Integer>();
+    static {
+        sBgSelectorBtnsMap.put(R.id.iv_bg_yellow, ResourceParser.YELLOW);
+        sBgSelectorBtnsMap.put(R.id.iv_bg_red, ResourceParser.RED);
+        sBgSelectorBtnsMap.put(R.id.iv_bg_blue, ResourceParser.BLUE);
+        sBgSelectorBtnsMap.put(R.id.iv_bg_green, ResourceParser.GREEN);
+        sBgSelectorBtnsMap.put(R.id.iv_bg_white, ResourceParser.WHITE);
+    }
+
+    private static final Map<Integer, Integer> sBgSelectorSelectionMap = new HashMap<Integer, Integer>();
+    static {
+        sBgSelectorSelectionMap.put(ResourceParser.YELLOW, R.id.iv_bg_yellow_select);
+        sBgSelectorSelectionMap.put(ResourceParser.RED, R.id.iv_bg_red_select);
+        sBgSelectorSelectionMap.put(ResourceParser.BLUE, R.id.iv_bg_blue_select);
+        sBgSelectorSelectionMap.put(ResourceParser.GREEN, R.id.iv_bg_green_select);
+        sBgSelectorSelectionMap.put(ResourceParser.WHITE, R.id.iv_bg_white_select);
+    }
+
+    private static final Map<Integer, Integer> sFontSizeBtnsMap = new HashMap<Integer, Integer>();
+    static {
+        sFontSizeBtnsMap.put(R.id.ll_font_large, ResourceParser.TEXT_LARGE);
+        sFontSizeBtnsMap.put(R.id.ll_font_small, ResourceParser.TEXT_SMALL);
+        sFontSizeBtnsMap.put(R.id.ll_font_normal, ResourceParser.TEXT_MEDIUM);
+        sFontSizeBtnsMap.put(R.id.ll_font_super, ResourceParser.TEXT_SUPER);
+    }
+
+    private static final Map<Integer, Integer> sFontSelectorSelectionMap = new HashMap<Integer, Integer>();
+    static {
+        sFontSelectorSelectionMap.put(ResourceParser.TEXT_LARGE, R.id.iv_large_select);
+        sFontSelectorSelectionMap.put(ResourceParser.TEXT_SMALL, R.id.iv_small_select);
+        sFontSelectorSelectionMap.put(ResourceParser.TEXT_MEDIUM, R.id.iv_medium_select);
+        sFontSelectorSelectionMap.put(ResourceParser.TEXT_SUPER, R.id.iv_super_select);
+    }
+
+    private static final String TAG = "NoteEditActivity";
+
+    private HeadViewHolder mNoteHeaderHolder;
+
+    private View mHeadViewPanel;
+
+    private View mNoteBgColorSelector;
+
+    private View mFontSizeSelector;
+
+    private EditText mNoteEditor;
+
+    private View mNoteEditorPanel;
+
+    private WorkingNote mWorkingNote;
+
+    private SharedPreferences mSharedPrefs;
+    private int mFontSizeId;
+
+    private static final String PREFERENCE_FONT_SIZE = "pref_font_size";
+
+    private static final int SHORTCUT_ICON_TITLE_MAX_LEN = 10;
+
+    public static final String TAG_CHECKED = String.valueOf('\u221A');
+    public static final String TAG_UNCHECKED = String.valueOf('\u25A1');
+
+    private LinearLayout mEditTextList;
+
+    private String mUserQuery;
+    private Pattern mPattern;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        this.setContentView(R.layout.note_edit);
+
+        if (savedInstanceState == null && !initActivityState(getIntent())) {
+            finish();
+            return;
+        }
+        initResources();
+    }
+
+    /**
+     * Current activity may be killed when the memory is low. Once it is killed, for another time
+     * user load this activity, we should restore the former state
+     */
+    @Override
+    protected void onRestoreInstanceState(Bundle savedInstanceState) {
+        super.onRestoreInstanceState(savedInstanceState);
+        if (savedInstanceState != null && savedInstanceState.containsKey(Intent.EXTRA_UID)) {
+            Intent intent = new Intent(Intent.ACTION_VIEW);
+            intent.putExtra(Intent.EXTRA_UID, savedInstanceState.getLong(Intent.EXTRA_UID));
+            if (!initActivityState(intent)) {
+                finish();
+                return;
+            }
+            Log.d(TAG, "Restoring from killed activity");
+        }
+    }
+
+    private boolean initActivityState(Intent intent) {
+        /**
+         * If the user specified the {@link Intent#ACTION_VIEW} but not provided with id,
+         * then jump to the NotesListActivity
+         */
+        mWorkingNote = null;
+        if (TextUtils.equals(Intent.ACTION_VIEW, intent.getAction())) {
+            long noteId = intent.getLongExtra(Intent.EXTRA_UID, 0);
+            mUserQuery = "";
+
+            /**
+             * Starting from the searched result
+             */
+            if (intent.hasExtra(SearchManager.EXTRA_DATA_KEY)) {
+                noteId = Long.parseLong(intent.getStringExtra(SearchManager.EXTRA_DATA_KEY));
+                mUserQuery = intent.getStringExtra(SearchManager.USER_QUERY);
+            }
+
+            if (!DataUtils.visibleInNoteDatabase(getContentResolver(), noteId, Notes.TYPE_NOTE)) {
+                Intent jump = new Intent(this, NotesListActivity.class);
+                startActivity(jump);
+                showToast(R.string.error_note_not_exist);
+                finish();
+                return false;
+            } else {
+                mWorkingNote = WorkingNote.load(this, noteId);
+                if (mWorkingNote == null) {
+                    Log.e(TAG, "load note failed with note id" + noteId);
+                    finish();
+                    return false;
+                }
+            }
+            getWindow().setSoftInputMode(
+                    WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN
+                            | WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE);
+        } else if(TextUtils.equals(Intent.ACTION_INSERT_OR_EDIT, intent.getAction())) {
+            // New note
+            long folderId = intent.getLongExtra(Notes.INTENT_EXTRA_FOLDER_ID, 0);
+            int widgetId = intent.getIntExtra(Notes.INTENT_EXTRA_WIDGET_ID,
+                    AppWidgetManager.INVALID_APPWIDGET_ID);
+            int widgetType = intent.getIntExtra(Notes.INTENT_EXTRA_WIDGET_TYPE,
+                    Notes.TYPE_WIDGET_INVALIDE);
+            int bgResId = intent.getIntExtra(Notes.INTENT_EXTRA_BACKGROUND_ID,
+                    ResourceParser.getDefaultBgId(this));
+
+            // Parse call-record note
+            String phoneNumber = intent.getStringExtra(Intent.EXTRA_PHONE_NUMBER);
+            long callDate = intent.getLongExtra(Notes.INTENT_EXTRA_CALL_DATE, 0);
+            if (callDate != 0 && phoneNumber != null) {
+                if (TextUtils.isEmpty(phoneNumber)) {
+                    Log.w(TAG, "The call record number is null");
+                }
+                long noteId = 0;
+                if ((noteId = DataUtils.getNoteIdByPhoneNumberAndCallDate(getContentResolver(),
+                        phoneNumber, callDate)) > 0) {
+                    mWorkingNote = WorkingNote.load(this, noteId);
+                    if (mWorkingNote == null) {
+                        Log.e(TAG, "load call note failed with note id" + noteId);
+                        finish();
+                        return false;
+                    }
+                } else {
+                    mWorkingNote = WorkingNote.createEmptyNote(this, folderId, widgetId,
+                            widgetType, bgResId);
+                    mWorkingNote.convertToCallNote(phoneNumber, callDate);
+                }
+            } else {
+                mWorkingNote = WorkingNote.createEmptyNote(this, folderId, widgetId, widgetType,
+                        bgResId);
+            }
+
+            getWindow().setSoftInputMode(
+                    WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE
+                            | WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE);
+        } else {
+            Log.e(TAG, "Intent not specified action, should not support");
+            finish();
+            return false;
+        }
+        mWorkingNote.setOnSettingStatusChangedListener(this);
+        return true;
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        initNoteScreen();
+    }
+
+    private void initNoteScreen() {
+        mNoteEditor.setTextAppearance(this, TextAppearanceResources
+                .getTexAppearanceResource(mFontSizeId));
+        if (mWorkingNote.getCheckListMode() == TextNote.MODE_CHECK_LIST) {
+            switchToListMode(mWorkingNote.getContent());
+        } else {
+            mNoteEditor.setText(getHighlightQueryResult(mWorkingNote.getContent(), mUserQuery));
+            mNoteEditor.setSelection(mNoteEditor.getText().length());
+        }
+        for (Integer id : sBgSelectorSelectionMap.keySet()) {
+            findViewById(sBgSelectorSelectionMap.get(id)).setVisibility(View.GONE);
+        }
+        mHeadViewPanel.setBackgroundResource(mWorkingNote.getTitleBgResId());
+        mNoteEditorPanel.setBackgroundResource(mWorkingNote.getBgColorResId());
+
+        mNoteHeaderHolder.tvModified.setText(DateUtils.formatDateTime(this,
+                mWorkingNote.getModifiedDate(), DateUtils.FORMAT_SHOW_DATE
+                        | DateUtils.FORMAT_NUMERIC_DATE | DateUtils.FORMAT_SHOW_TIME
+                        | DateUtils.FORMAT_SHOW_YEAR));
+
+        /**
+         * TODO: Add the menu for setting alert. Currently disable it because the DateTimePicker
+         * is not ready
+         */
+        showAlertHeader();
+    }
+
+    private void showAlertHeader() {
+        if (mWorkingNote.hasClockAlert()) {
+            long time = System.currentTimeMillis();
+            if (time > mWorkingNote.getAlertDate()) {
+                mNoteHeaderHolder.tvAlertDate.setText(R.string.note_alert_expired);
+            } else {
+                mNoteHeaderHolder.tvAlertDate.setText(DateUtils.getRelativeTimeSpanString(
+                        mWorkingNote.getAlertDate(), time, DateUtils.MINUTE_IN_MILLIS));
+            }
+            mNoteHeaderHolder.tvAlertDate.setVisibility(View.VISIBLE);
+            mNoteHeaderHolder.ivAlertIcon.setVisibility(View.VISIBLE);
+        } else {
+            mNoteHeaderHolder.tvAlertDate.setVisibility(View.GONE);
+            mNoteHeaderHolder.ivAlertIcon.setVisibility(View.GONE);
+        };
+    }
+
+    @Override
+    protected void onNewIntent(Intent intent) {
+        super.onNewIntent(intent);
+        initActivityState(intent);
+    }
+
+    @Override
+    protected void onSaveInstanceState(Bundle outState) {
+        super.onSaveInstanceState(outState);
+        /**
+         * For new note without note id, we should firstly save it to
+         * generate a id. If the editing note is not worth saving, there
+         * is no id which is equivalent to create new note
+         */
+        if (!mWorkingNote.existInDatabase()) {
+            saveNote();
+        }
+        outState.putLong(Intent.EXTRA_UID, mWorkingNote.getNoteId());
+        Log.d(TAG, "Save working note id: " + mWorkingNote.getNoteId() + " onSaveInstanceState");
+    }
+
+    @Override
+    public boolean dispatchTouchEvent(MotionEvent ev) {
+        if (mNoteBgColorSelector.getVisibility() == View.VISIBLE
+                && !inRangeOfView(mNoteBgColorSelector, ev)) {
+            mNoteBgColorSelector.setVisibility(View.GONE);
+            return true;
+        }
+
+        if (mFontSizeSelector.getVisibility() == View.VISIBLE
+                && !inRangeOfView(mFontSizeSelector, ev)) {
+            mFontSizeSelector.setVisibility(View.GONE);
+            return true;
+        }
+        return super.dispatchTouchEvent(ev);
+    }
+
+    private boolean inRangeOfView(View view, MotionEvent ev) {
+        int []location = new int[2];
+        view.getLocationOnScreen(location);
+        int x = location[0];
+        int y = location[1];
+        if (ev.getX() < x
+                || ev.getX() > (x + view.getWidth())
+                || ev.getY() < y
+                || ev.getY() > (y + view.getHeight())) {
+                    return false;
+                }
+        return true;
+    }
+
+    private void initResources() {
+        mHeadViewPanel = findViewById(R.id.note_title);
+        mNoteHeaderHolder = new HeadViewHolder();
+        mNoteHeaderHolder.tvModified = (TextView) findViewById(R.id.tv_modified_date);
+        mNoteHeaderHolder.ivAlertIcon = (ImageView) findViewById(R.id.iv_alert_icon);
+        mNoteHeaderHolder.tvAlertDate = (TextView) findViewById(R.id.tv_alert_date);
+        mNoteHeaderHolder.ibSetBgColor = (ImageView) findViewById(R.id.btn_set_bg_color);
+        mNoteHeaderHolder.ibSetBgColor.setOnClickListener(this);
+        mNoteEditor = (EditText) findViewById(R.id.note_edit_view);
+        mNoteEditorPanel = findViewById(R.id.sv_note_edit);
+        mNoteBgColorSelector = findViewById(R.id.note_bg_color_selector);
+        for (int id : sBgSelectorBtnsMap.keySet()) {
+            ImageView iv = (ImageView) findViewById(id);
+            iv.setOnClickListener(this);
+        }
+
+        mFontSizeSelector = findViewById(R.id.font_size_selector);
+        for (int id : sFontSizeBtnsMap.keySet()) {
+            View view = findViewById(id);
+            view.setOnClickListener(this);
+        };
+        mSharedPrefs = PreferenceManager.getDefaultSharedPreferences(this);
+        mFontSizeId = mSharedPrefs.getInt(PREFERENCE_FONT_SIZE, ResourceParser.BG_DEFAULT_FONT_SIZE);
+        /**
+         * HACKME: Fix bug of store the resource id in shared preference.
+         * The id may larger than the length of resources, in this case,
+         * return the {@link ResourceParser#BG_DEFAULT_FONT_SIZE}
+         */
+        if(mFontSizeId >= TextAppearanceResources.getResourcesSize()) {
+            mFontSizeId = ResourceParser.BG_DEFAULT_FONT_SIZE;
+        }
+        mEditTextList = (LinearLayout) findViewById(R.id.note_edit_list);
+    }
+
+    @Override
+    protected void onPause() {
+        super.onPause();
+        if(saveNote()) {
+            Log.d(TAG, "Note data was saved with length:" + mWorkingNote.getContent().length());
+        }
+        clearSettingState();
+    }
+
+    private void updateWidget() {
+        Intent intent = new Intent(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
+        if (mWorkingNote.getWidgetType() == Notes.TYPE_WIDGET_2X) {
+            intent.setClass(this, NoteWidgetProvider_2x.class);
+        } else if (mWorkingNote.getWidgetType() == Notes.TYPE_WIDGET_4X) {
+            intent.setClass(this, NoteWidgetProvider_4x.class);
+        } else {
+            Log.e(TAG, "Unspported widget type");
+            return;
+        }
+
+        intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS, new int[] {
+            mWorkingNote.getWidgetId()
+        });
+
+        sendBroadcast(intent);
+        setResult(RESULT_OK, intent);
+    }
+
+    public void onClick(View v) {
+        int id = v.getId();
+        if (id == R.id.btn_set_bg_color) {
+            mNoteBgColorSelector.setVisibility(View.VISIBLE);
+            findViewById(sBgSelectorSelectionMap.get(mWorkingNote.getBgColorId())).setVisibility(
+                    -                    View.VISIBLE);
+        } else if (sBgSelectorBtnsMap.containsKey(id)) {
+            findViewById(sBgSelectorSelectionMap.get(mWorkingNote.getBgColorId())).setVisibility(
+                    View.GONE);
+            mWorkingNote.setBgColorId(sBgSelectorBtnsMap.get(id));
+            mNoteBgColorSelector.setVisibility(View.GONE);
+        } else if (sFontSizeBtnsMap.containsKey(id)) {
+            findViewById(sFontSelectorSelectionMap.get(mFontSizeId)).setVisibility(View.GONE);
+            mFontSizeId = sFontSizeBtnsMap.get(id);
+            mSharedPrefs.edit().putInt(PREFERENCE_FONT_SIZE, mFontSizeId).commit();
+            findViewById(sFontSelectorSelectionMap.get(mFontSizeId)).setVisibility(View.VISIBLE);
+            if (mWorkingNote.getCheckListMode() == TextNote.MODE_CHECK_LIST) {
+                getWorkingText();
+                switchToListMode(mWorkingNote.getContent());
+            } else {
+                mNoteEditor.setTextAppearance(this,
+                        TextAppearanceResources.getTexAppearanceResource(mFontSizeId));
+            }
+            mFontSizeSelector.setVisibility(View.GONE);
+        }
+    }
+
+    @Override
+    public void onBackPressed() {
+        if(clearSettingState()) {
+            return;
+        }
+
+        saveNote();
+        super.onBackPressed();
+    }
+
+    private boolean clearSettingState() {
+        if (mNoteBgColorSelector.getVisibility() == View.VISIBLE) {
+            mNoteBgColorSelector.setVisibility(View.GONE);
+            return true;
+        } else if (mFontSizeSelector.getVisibility() == View.VISIBLE) {
+            mFontSizeSelector.setVisibility(View.GONE);
+            return true;
+        }
+        return false;
+    }
+
+    public void onBackgroundColorChanged() {
+        findViewById(sBgSelectorSelectionMap.get(mWorkingNote.getBgColorId())).setVisibility(
+                View.VISIBLE);
+        mNoteEditorPanel.setBackgroundResource(mWorkingNote.getBgColorResId());
+        mHeadViewPanel.setBackgroundResource(mWorkingNote.getTitleBgResId());
+    }
+
+    @Override
+    public boolean onPrepareOptionsMenu(Menu menu) {
+        if (isFinishing()) {
+            return true;
+        }
+        clearSettingState();
+        menu.clear();
+        if (mWorkingNote.getFolderId() == Notes.ID_CALL_RECORD_FOLDER) {
+            getMenuInflater().inflate(R.menu.call_note_edit, menu);
+        } else {
+            getMenuInflater().inflate(R.menu.note_edit, menu);
+        }
+        if (mWorkingNote.getCheckListMode() == TextNote.MODE_CHECK_LIST) {
+            menu.findItem(R.id.menu_list_mode).setTitle(R.string.menu_normal_mode);
+        } else {
+            menu.findItem(R.id.menu_list_mode).setTitle(R.string.menu_list_mode);
+        }
+        if (mWorkingNote.hasClockAlert()) {
+            menu.findItem(R.id.menu_alert).setVisible(false);
+        } else {
+            menu.findItem(R.id.menu_delete_remind).setVisible(false);
+        }
+        return true;
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        switch (item.getItemId()) {
+            case R.id.menu_new_note:
+                createNewNote();
+                break;
+            case R.id.menu_delete:
+                AlertDialog.Builder builder = new AlertDialog.Builder(this);
+                builder.setTitle(getString(R.string.alert_title_delete));
+                builder.setIcon(android.R.drawable.ic_dialog_alert);
+                builder.setMessage(getString(R.string.alert_message_delete_note));
+                builder.setPositiveButton(android.R.string.ok,
+                        new DialogInterface.OnClickListener() {
+                            public void onClick(DialogInterface dialog, int which) {
+                                deleteCurrentNote();
+                                finish();
+                            }
+                        });
+                builder.setNegativeButton(android.R.string.cancel, null);
+                builder.show();
+                break;
+            case R.id.menu_font_size:
+                mFontSizeSelector.setVisibility(View.VISIBLE);
+                findViewById(sFontSelectorSelectionMap.get(mFontSizeId)).setVisibility(View.VISIBLE);
+                break;
+            case R.id.menu_list_mode:
+                mWorkingNote.setCheckListMode(mWorkingNote.getCheckListMode() == 0 ?
+                        TextNote.MODE_CHECK_LIST : 0);
+                break;
+            case R.id.menu_share:
+                getWorkingText();
+                sendTo(this, mWorkingNote.getContent());
+                break;
+            case R.id.menu_send_to_desktop:
+                sendToDesktop();
+                break;
+            case R.id.menu_alert:
+                setReminder();
+                break;
+            case R.id.menu_delete_remind:
+                mWorkingNote.setAlertDate(0, false);
+                break;
+            default:
+                break;
+        }
+        return true;
+    }
+
+    private void setReminder() {
+        DateTimePickerDialog d = new DateTimePickerDialog(this, System.currentTimeMillis());
+        d.setOnDateTimeSetListener(new OnDateTimeSetListener() {
+            public void OnDateTimeSet(AlertDialog dialog, long date) {
+                mWorkingNote.setAlertDate(date	, true);
+            }
+        });
+        d.show();
+    }
+
+    /**
+     * Share note to apps that support {@link Intent#ACTION_SEND} action
+     * and {@text/plain} type
+     */
+    private void sendTo(Context context, String info) {
+        Intent intent = new Intent(Intent.ACTION_SEND);
+        intent.putExtra(Intent.EXTRA_TEXT, info);
+        intent.setType("text/plain");
+        context.startActivity(intent);
+    }
+
+    private void createNewNote() {
+        // Firstly, save current editing notes
+        saveNote();
+
+        // For safety, start a new NoteEditActivity
+        finish();
+        Intent intent = new Intent(this, NoteEditActivity.class);
+        intent.setAction(Intent.ACTION_INSERT_OR_EDIT);
+        intent.putExtra(Notes.INTENT_EXTRA_FOLDER_ID, mWorkingNote.getFolderId());
+        startActivity(intent);
+    }
+
+    private void deleteCurrentNote() {
+        if (mWorkingNote.existInDatabase()) {
+            HashSet<Long> ids = new HashSet<Long>();
+            long id = mWorkingNote.getNoteId();
+            if (id != Notes.ID_ROOT_FOLDER) {
+                ids.add(id);
+            } else {
+                Log.d(TAG, "Wrong note id, should not happen");
+            }
+            if (!isSyncMode()) {
+                if (!DataUtils.batchDeleteNotes(getContentResolver(), ids)) {
+                    Log.e(TAG, "Delete Note error");
+                }
+            } else {
+                if (!DataUtils.batchMoveToFolder(getContentResolver(), ids, Notes.ID_TRASH_FOLER)) {
+                    Log.e(TAG, "Move notes to trash folder error, should not happens");
+                }
+            }
+        }
+        mWorkingNote.markDeleted(true);
+    }
+
+    private boolean isSyncMode() {
+        return NotesPreferenceActivity.getSyncAccountName(this).trim().length() > 0;
+    }
+
+    public void onClockAlertChanged(long date, boolean set) {
+        /**
+         * User could set clock to an unsaved note, so before setting the
+         * alert clock, we should save the note first
+         */
+        if (!mWorkingNote.existInDatabase()) {
+            saveNote();
+        }
+        if (mWorkingNote.getNoteId() > 0) {
+            Intent intent = new Intent(this, AlarmReceiver.class);
+            intent.setData(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, mWorkingNote.getNoteId()));
+            PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, intent, 0);
+            AlarmManager alarmManager = ((AlarmManager) getSystemService(ALARM_SERVICE));
+            showAlertHeader();
+            if(!set) {
+                alarmManager.cancel(pendingIntent);
+            } else {
+                alarmManager.set(AlarmManager.RTC_WAKEUP, date, pendingIntent);
+            }
+        } else {
+            /**
+             * There is the condition that user has input nothing (the note is
+             * not worthy saving), we have no note id, remind the user that he
+             * should input something
+             */
+            Log.e(TAG, "Clock alert setting error");
+            showToast(R.string.error_note_empty_for_clock);
+        }
+    }
+
+    public void onWidgetChanged() {
+        updateWidget();
+    }
+
+    public void onEditTextDelete(int index, String text) {
+        int childCount = mEditTextList.getChildCount();
+        if (childCount == 1) {
+            return;
+        }
+
+        for (int i = index + 1; i < childCount; i++) {
+            ((NoteEditText) mEditTextList.getChildAt(i).findViewById(R.id.et_edit_text))
+                    .setIndex(i - 1);
+        }
+
+        mEditTextList.removeViewAt(index);
+        NoteEditText edit = null;
+        if(index == 0) {
+            edit = (NoteEditText) mEditTextList.getChildAt(0).findViewById(
+                    R.id.et_edit_text);
+        } else {
+            edit = (NoteEditText) mEditTextList.getChildAt(index - 1).findViewById(
+                    R.id.et_edit_text);
+        }
+        int length = edit.length();
+        edit.append(text);
+        edit.requestFocus();
+        edit.setSelection(length);
+    }
+
+    public void onEditTextEnter(int index, String text) {
+        /**
+         * Should not happen, check for debug
+         */
+        if(index > mEditTextList.getChildCount()) {
+            Log.e(TAG, "Index out of mEditTextList boundrary, should not happen");
+        }
+
+        View view = getListItem(text, index);
+        mEditTextList.addView(view, index);
+        NoteEditText edit = (NoteEditText) view.findViewById(R.id.et_edit_text);
+        edit.requestFocus();
+        edit.setSelection(0);
+        for (int i = index + 1; i < mEditTextList.getChildCount(); i++) {
+            ((NoteEditText) mEditTextList.getChildAt(i).findViewById(R.id.et_edit_text))
+                    .setIndex(i);
+        }
+    }
+
+    private void switchToListMode(String text) {
+        mEditTextList.removeAllViews();
+        String[] items = text.split("\n");
+        int index = 0;
+        for (String item : items) {
+            if(!TextUtils.isEmpty(item)) {
+                mEditTextList.addView(getListItem(item, index));
+                index++;
+            }
+        }
+        mEditTextList.addView(getListItem("", index));
+        mEditTextList.getChildAt(index).findViewById(R.id.et_edit_text).requestFocus();
+
+        mNoteEditor.setVisibility(View.GONE);
+        mEditTextList.setVisibility(View.VISIBLE);
+    }
+
+    private Spannable getHighlightQueryResult(String fullText, String userQuery) {
+        SpannableString spannable = new SpannableString(fullText == null ? "" : fullText);
+        if (!TextUtils.isEmpty(userQuery)) {
+            mPattern = Pattern.compile(userQuery);
+            Matcher m = mPattern.matcher(fullText);
+            int start = 0;
+            while (m.find(start)) {
+                spannable.setSpan(
+                        new BackgroundColorSpan(this.getResources().getColor(
+                                R.color.user_query_highlight)), m.start(), m.end(),
+                        Spannable.SPAN_INCLUSIVE_EXCLUSIVE);
+                start = m.end();
+            }
+        }
+        return spannable;
+    }
+
+    private View getListItem(String item, int index) {
+        View view = LayoutInflater.from(this).inflate(R.layout.note_edit_list_item, null);
+        final NoteEditText edit = (NoteEditText) view.findViewById(R.id.et_edit_text);
+        edit.setTextAppearance(this, TextAppearanceResources.getTexAppearanceResource(mFontSizeId));
+        CheckBox cb = ((CheckBox) view.findViewById(R.id.cb_edit_item));
+        cb.setOnCheckedChangeListener(new OnCheckedChangeListener() {
+            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
+                if (isChecked) {
+                    edit.setPaintFlags(edit.getPaintFlags() | Paint.STRIKE_THRU_TEXT_FLAG);
+                } else {
+                    edit.setPaintFlags(Paint.ANTI_ALIAS_FLAG | Paint.DEV_KERN_TEXT_FLAG);
+                }
+            }
+        });
+
+        if (item.startsWith(TAG_CHECKED)) {
+            cb.setChecked(true);
+            edit.setPaintFlags(edit.getPaintFlags() | Paint.STRIKE_THRU_TEXT_FLAG);
+            item = item.substring(TAG_CHECKED.length(), item.length()).trim();
+        } else if (item.startsWith(TAG_UNCHECKED)) {
+            cb.setChecked(false);
+            edit.setPaintFlags(Paint.ANTI_ALIAS_FLAG | Paint.DEV_KERN_TEXT_FLAG);
+            item = item.substring(TAG_UNCHECKED.length(), item.length()).trim();
+        }
+
+        edit.setOnTextViewChangeListener(this);
+        edit.setIndex(index);
+        edit.setText(getHighlightQueryResult(item, mUserQuery));
+        return view;
+    }
+
+    public void onTextChange(int index, boolean hasText) {
+        if (index >= mEditTextList.getChildCount()) {
+            Log.e(TAG, "Wrong index, should not happen");
+            return;
+        }
+        if(hasText) {
+            mEditTextList.getChildAt(index).findViewById(R.id.cb_edit_item).setVisibility(View.VISIBLE);
+        } else {
+            mEditTextList.getChildAt(index).findViewById(R.id.cb_edit_item).setVisibility(View.GONE);
+        }
+    }
+
+    public void onCheckListModeChanged(int oldMode, int newMode) {
+        if (newMode == TextNote.MODE_CHECK_LIST) {
+            switchToListMode(mNoteEditor.getText().toString());
+        } else {
+            if (!getWorkingText()) {
+                mWorkingNote.setWorkingText(mWorkingNote.getContent().replace(TAG_UNCHECKED + " ",
+                        ""));
+            }
+            mNoteEditor.setText(getHighlightQueryResult(mWorkingNote.getContent(), mUserQuery));
+            mEditTextList.setVisibility(View.GONE);
+            mNoteEditor.setVisibility(View.VISIBLE);
+        }
+    }
+
+    private boolean getWorkingText() {
+        boolean hasChecked = false;
+        if (mWorkingNote.getCheckListMode() == TextNote.MODE_CHECK_LIST) {
+            StringBuilder sb = new StringBuilder();
+            for (int i = 0; i < mEditTextList.getChildCount(); i++) {
+                View view = mEditTextList.getChildAt(i);
+                NoteEditText edit = (NoteEditText) view.findViewById(R.id.et_edit_text);
+                if (!TextUtils.isEmpty(edit.getText())) {
+                    if (((CheckBox) view.findViewById(R.id.cb_edit_item)).isChecked()) {
+                        sb.append(TAG_CHECKED).append(" ").append(edit.getText()).append("\n");
+                        hasChecked = true;
+                    } else {
+                        sb.append(TAG_UNCHECKED).append(" ").append(edit.getText()).append("\n");
+                    }
+                }
+            }
+            mWorkingNote.setWorkingText(sb.toString());
+        } else {
+            mWorkingNote.setWorkingText(mNoteEditor.getText().toString());
+        }
+        return hasChecked;
+    }
+
+    private boolean saveNote() {
+        getWorkingText();
+        boolean saved = mWorkingNote.saveNote();
+        if (saved) {
+            /**
+             * There are two modes from List view to edit view, open one note,
+             * create/edit a node. Opening node requires to the original
+             * position in the list when back from edit view, while creating a
+             * new node requires to the top of the list. This code
+             * {@link #RESULT_OK} is used to identify the create/edit state
+             */
+            setResult(RESULT_OK);
+        }
+        return saved;
+    }
+
+    private void sendToDesktop() {
+        /**
+         * Before send message to home, we should make sure that current
+         * editing note is exists in databases. So, for new note, firstly
+         * save it
+         */
+        if (!mWorkingNote.existInDatabase()) {
+            saveNote();
+        }
+
+        if (mWorkingNote.getNoteId() > 0) {
+            Intent sender = new Intent();
+            Intent shortcutIntent = new Intent(this, NoteEditActivity.class);
+            shortcutIntent.setAction(Intent.ACTION_VIEW);
+            shortcutIntent.putExtra(Intent.EXTRA_UID, mWorkingNote.getNoteId());
+            sender.putExtra(Intent.EXTRA_SHORTCUT_INTENT, shortcutIntent);
+            sender.putExtra(Intent.EXTRA_SHORTCUT_NAME,
+                    makeShortcutIconTitle(mWorkingNote.getContent()));
+            sender.putExtra(Intent.EXTRA_SHORTCUT_ICON_RESOURCE,
+                    Intent.ShortcutIconResource.fromContext(this, R.drawable.icon_app));
+            sender.putExtra("duplicate", true);
+            sender.setAction("com.android.launcher.action.INSTALL_SHORTCUT");
+            showToast(R.string.info_note_enter_desktop);
+            sendBroadcast(sender);
+        } else {
+            /**
+             * There is the condition that user has input nothing (the note is
+             * not worthy saving), we have no note id, remind the user that he
+             * should input something
+             */
+            Log.e(TAG, "Send to desktop error");
+            showToast(R.string.error_note_empty_for_send_to_desktop);
+        }
+    }
+
+    private String makeShortcutIconTitle(String content) {
+        content = content.replace(TAG_CHECKED, "");
+        content = content.replace(TAG_UNCHECKED, "");
+        return content.length() > SHORTCUT_ICON_TITLE_MAX_LEN ? content.substring(0,
+                SHORTCUT_ICON_TITLE_MAX_LEN) : content;
+    }
+
+    private void showToast(int resId) {
+        showToast(resId, Toast.LENGTH_SHORT);
+    }
+
+    private void showToast(int resId, int duration) {
+        Toast.makeText(this, resId, duration).show();
+    }
+}

java/net/micode/notes/ui/NoteEditText.java

@@ -0,0 +1,268 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了一个名为NoteEditText的自定义EditText类，它在继承安卓原生EditText的基础上，添加了诸多针对特定业务需求的功能逻辑。主要用于处理文本编辑过程中的一些交互操作，比如按键按下与抬起时的逻辑（像删除、回车键按下等情况）、触摸事件处理、焦点变化处理以及上下文菜单创建等，同时定义了一个接口用于和外部代码进行交互，通知外部文本编辑相关的状态变化情况，整体旨在为笔记编辑等类似场景下的文本输入操作提供更贴合业务需求的交互功能。
+函数分析
+构造函数相关
+NoteEditText(Context context)、NoteEditText(Context context, AttributeSet attrs)、NoteEditText(Context context, AttributeSet attrs, int defStyle)：
+所属类：NoteEditText
+功能：
+第一个构造函数只接收Context参数，调用父类（EditText）构造函数并传入Context和null，同时初始化成员变量mIndex为0，用于记录当前文本编辑框的某种索引（可能与多个编辑框排序等相关）。
+第二个构造函数接收Context和AttributeSet参数，调用父类构造函数并传入Context、AttributeSet以及指定的编辑框样式（android.R.attr.editTextStyle），用于按照传入的属性集合和默认样式来初始化编辑框。
+第三个构造函数接收Context、AttributeSet和defStyle参数，调用父类构造函数传入对应参数进行初始化，不过其内部暂时没有额外自定义的初始化逻辑（代码中 TODO Auto-generated constructor stub 提示后续可能还有完善的地方）。
+触摸事件处理函数
+onTouchEvent(MotionEvent event)：
+所属类：NoteEditText
+功能：重写了父类的onTouchEvent方法来处理触摸操作相关逻辑。当触摸事件的动作是ACTION_DOWN（手指按下屏幕）时：
+首先获取触摸点相对于编辑框内部的坐标（通过减去总内边距并加上滚动偏移量等计算），然后根据触摸点的垂直坐标获取所在的文本行，再根据水平坐标获取该行对应的文本偏移量，最后通过Selection.setSelection方法将文本选中位置设置为该偏移量对应的位置，实现触摸选中文本的功能，使得用户触摸文本区域时能方便地定位和选中相应文本内容，符合常见的文本编辑交互习惯。
+最后返回调用父类onTouchEvent方法的结果，保证其他未处理的触摸相关逻辑能按照原生EditText的行为继续执行。
+按键按下处理函数
+onKeyDown(int keyCode, KeyEvent event)：
+所属类：NoteEditText
+功能：重写了父类的onKeyDown方法来处理按键按下的相关逻辑。根据按下的不同按键码（keyCode）进行不同操作：
+当按下的是回车键（KEYCODE_ENTER）时，如果设置了OnTextViewChangeListener监听器（用于和外部代码交互通知文本编辑状态变化的接口），则直接返回false，这可能是为了后续在onKeyUp方法中统一处理回车键抬起的逻辑或者让外部代码有更多控制权决定回车键按下后的具体行为（比如是否添加新的编辑文本等）。
+当按下的是删除键（KEYCODE_DEL）时，记录当前文本选中位置的起始点（通过getSelectionStart方法获取并赋值给mSelectionStartBeforeDelete变量），用于后续在删除键抬起时判断是否满足特定的删除文本逻辑，比如是否删除当前编辑框的全部文本等情况。
+对于其他按键按下情况，则不做额外自定义处理，直接执行父类的onKeyDown方法逻辑。
+按键抬起处理函数
+onKeyUp(int keyCode, KeyEvent event)：
+所属类：NoteEditText
+功能：重写了父类的onKeyUp方法来处理按键抬起的相关逻辑。根据抬起的不同按键码（keyCode）进行不同操作：
+当按键码是删除键（KEYCODE_DEL）时，如果设置了OnTextViewChangeListener监听器，会进一步判断，如果当前文本选中位置起始点为0且当前编辑框的索引（mIndex）不为0，则调用监听器的onEditTextDelete方法并传入当前编辑框索引以及编辑框内的文本内容（通过getText方法获取并转换为字符串），通知外部代码当前编辑框文本被删除的情况，最后返回true表示该按键抬起事件已被处理，避免父类重复处理。若没有设置监听器，则打印日志提示监听器未设置。
+当按键码是回车键（KEYCODE_ENTER）时，如果设置了OnTextViewChangeListener监听器，先获取当前文本选中位置的起始点，然后截取从该起始点到文本末尾的内容作为新文本，将编辑框内文本设置为从开头到选中起始点的内容（相当于模拟了在选中位置插入新文本的操作），接着调用监听器的onEditTextEnter方法并传入当前编辑框索引加1（可能表示下一个编辑框的索引）以及新文本内容，通知外部代码回车键按下后添加新文本的情况，若没有设置监听器同样打印日志提示监听器未设置。
+对于其他按键抬起情况，则执行父类的onKeyUp方法逻辑。
+焦点变化处理函数
+onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect)：
+所属类：NoteEditText
+功能：重写了父类的方法来处理编辑框焦点变化的相关逻辑。当焦点发生变化时，如果设置了OnTextViewChangeListener监听器，会进一步判断：
+如果编辑框失去焦点（focused为false）并且编辑框内文本为空（通过TextUtils.isEmpty方法判断），则调用监听器的onTextChange方法并传入当前编辑框索引以及false，通知外部代码当前编辑框文本为空且失去焦点的情况，外部代码可以据此隐藏一些相关的操作选项等。
+如果编辑框获得焦点或者虽然失去焦点但文本不为空，则调用监听器的onTextChange方法并传入当前编辑框索引以及true，通知外部代码编辑框文本状态变化情况，外部代码可以据此显示相关操作选项等。
+最后无论哪种情况，都会调用父类的onFocusChanged方法保证原生的焦点变化相关逻辑继续执行，比如可能涉及界面重绘等其他系统行为。
+上下文菜单创建函数
+onCreateContextMenu(ContextMenu menu)：
+所属类：NoteEditText
+功能：重写了父类的方法来创建上下文菜单（通常通过长按文本编辑框等操作触发）。在函数内部：
+首先判断编辑框内的文本是否是实现了Spanned接口的类型（意味着文本可能包含了一些样式、链接等特殊内容），如果是，则获取当前文本选中区域的起始和结束位置，确定最小和最大位置。
+通过getSpans方法从文本中获取位于选中区域内的URLSpan类型的对象数组（URLSpan用于表示文本中的链接），如果数组长度为1（即只选中了一个链接），则遍历预定义的链接协议与对应资源ID的映射表（sSchemaActionResMap），查找该链接的协议（通过getURL方法获取链接字符串并判断其开头协议部分）对应的资源ID，如果找到则使用对应的ID，如果没找到则使用默认的ID（R.string.note_link_other）。
+使用找到的资源ID通过menu.add方法在上下文菜单中添加一个菜单项，并为该菜单项设置点击监听器，在监听器的onMenuItemClick方法中，调用对应的URLSpan对象的onClick方法（通常会触发打开链接对应的页面等操作），实现长按链接弹出对应操作选项并点击执行相应操作的功能，最后调用父类的onCreateContextMenu方法保证原生的上下文菜单创建相关逻辑继续执行，比如添加系统默认的一些菜单选项等。
+接口相关方法
+setIndex(int index)：
+所属类：NoteEditText
+功能：用于设置当前编辑框的索引值（mIndex），接收一个整数参数，将其赋值给mIndex变量，外部代码可以通过这个方法来明确当前编辑框在一组编辑框中的顺序等信息，便于后续根据索引进行相关逻辑处理，比如判断是否是第一个编辑框等情况。
+setOnTextViewChangeListener(OnTextViewChangeListener listener)：
+所属类：NoteEditText
+功能：用于设置OnTextViewChangeListener监听器，接收一个实现了该接口的对象作为参数，将其赋值给mOnTextViewChangeListener变量，外部代码通过实现该接口并传入对应的监听器对象，就可以在文本编辑框发生文本删除、回车键按下、文本状态变化等情况时接收到通知并执行相应的业务逻辑，增强了该自定义编辑框与外部代码之间的交互性。
+ */
+
+package net.micode.notes.ui;
+
+import android.content.Context;
+import android.graphics.Rect;
+import android.text.Layout;
+import android.text.Selection;
+import android.text.Spanned;
+import android.text.TextUtils;
+import android.text.style.URLSpan;
+import android.util.AttributeSet;
+import android.util.Log;
+import android.view.ContextMenu;
+import android.view.KeyEvent;
+import android.view.MenuItem;
+import android.view.MenuItem.OnMenuItemClickListener;
+import android.view.MotionEvent;
+import android.widget.EditText;
+
+import net.micode.notes.R;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class NoteEditText extends EditText {
+    private static final String TAG = "NoteEditText";
+    private int mIndex;
+    private int mSelectionStartBeforeDelete;
+
+    private static final String SCHEME_TEL = "tel:" ;
+    private static final String SCHEME_HTTP = "http:" ;
+    private static final String SCHEME_EMAIL = "mailto:" ;
+
+    private static final Map<String, Integer> sSchemaActionResMap = new HashMap<String, Integer>();
+    static {
+        sSchemaActionResMap.put(SCHEME_TEL, R.string.note_link_tel);
+        sSchemaActionResMap.put(SCHEME_HTTP, R.string.note_link_web);
+        sSchemaActionResMap.put(SCHEME_EMAIL, R.string.note_link_email);
+    }
+
+    /**
+     * Call by the {@link NoteEditActivity} to delete or add edit text
+     */
+    public interface OnTextViewChangeListener {
+        /**
+         * Delete current edit text when {@link KeyEvent#KEYCODE_DEL} happens
+         * and the text is null
+         */
+        void onEditTextDelete(int index, String text);
+
+        /**
+         * Add edit text after current edit text when {@link KeyEvent#KEYCODE_ENTER}
+         * happen
+         */
+        void onEditTextEnter(int index, String text);
+
+        /**
+         * Hide or show item option when text change
+         */
+        void onTextChange(int index, boolean hasText);
+    }
+
+    private OnTextViewChangeListener mOnTextViewChangeListener;
+
+    public NoteEditText(Context context) {
+        super(context, null);
+        mIndex = 0;
+    }
+
+    public void setIndex(int index) {
+        mIndex = index;
+    }
+
+    public void setOnTextViewChangeListener(OnTextViewChangeListener listener) {
+        mOnTextViewChangeListener = listener;
+    }
+
+    public NoteEditText(Context context, AttributeSet attrs) {
+        super(context, attrs, android.R.attr.editTextStyle);
+    }
+
+    public NoteEditText(Context context, AttributeSet attrs, int defStyle) {
+        super(context, attrs, defStyle);
+        // TODO Auto-generated constructor stub
+    }
+
+    @Override
+    public boolean onTouchEvent(MotionEvent event) {
+        switch (event.getAction()) {
+            case MotionEvent.ACTION_DOWN:
+
+                int x = (int) event.getX();
+                int y = (int) event.getY();
+                x -= getTotalPaddingLeft();
+                y -= getTotalPaddingTop();
+                x += getScrollX();
+                y += getScrollY();
+
+                Layout layout = getLayout();
+                int line = layout.getLineForVertical(y);
+                int off = layout.getOffsetForHorizontal(line, x);
+                Selection.setSelection(getText(), off);
+                break;
+        }
+
+        return super.onTouchEvent(event);
+    }
+
+    @Override
+    public boolean onKeyDown(int keyCode, KeyEvent event) {
+        switch (keyCode) {
+            case KeyEvent.KEYCODE_ENTER:
+                if (mOnTextViewChangeListener != null) {
+                    return false;
+                }
+                break;
+            case KeyEvent.KEYCODE_DEL:
+                mSelectionStartBeforeDelete = getSelectionStart();
+                break;
+            default:
+                break;
+        }
+        return super.onKeyDown(keyCode, event);
+    }
+
+    @Override
+    public boolean onKeyUp(int keyCode, KeyEvent event) {
+        switch(keyCode) {
+            case KeyEvent.KEYCODE_DEL:
+                if (mOnTextViewChangeListener != null) {
+                    if (0 == mSelectionStartBeforeDelete && mIndex != 0) {
+                        mOnTextViewChangeListener.onEditTextDelete(mIndex, getText().toString());
+                        return true;
+                    }
+                } else {
+                    Log.d(TAG, "OnTextViewChangeListener was not seted");
+                }
+                break;
+            case KeyEvent.KEYCODE_ENTER:
+                if (mOnTextViewChangeListener != null) {
+                    int selectionStart = getSelectionStart();
+                    String text = getText().subSequence(selectionStart, length()).toString();
+                    setText(getText().subSequence(0, selectionStart));
+                    mOnTextViewChangeListener.onEditTextEnter(mIndex + 1, text);
+                } else {
+                    Log.d(TAG, "OnTextViewChangeListener was not seted");
+                }
+                break;
+            default:
+                break;
+        }
+        return super.onKeyUp(keyCode, event);
+    }
+
+    @Override
+    protected void onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect) {
+        if (mOnTextViewChangeListener != null) {
+            if (!focused && TextUtils.isEmpty(getText())) {
+                mOnTextViewChangeListener.onTextChange(mIndex, false);
+            } else {
+                mOnTextViewChangeListener.onTextChange(mIndex, true);
+            }
+        }
+        super.onFocusChanged(focused, direction, previouslyFocusedRect);
+    }
+
+    @Override
+    protected void onCreateContextMenu(ContextMenu menu) {
+        if (getText() instanceof Spanned) {
+            int selStart = getSelectionStart();
+            int selEnd = getSelectionEnd();
+
+            int min = Math.min(selStart, selEnd);
+            int max = Math.max(selStart, selEnd);
+
+            final URLSpan[] urls = ((Spanned) getText()).getSpans(min, max, URLSpan.class);
+            if (urls.length == 1) {
+                int defaultResId = 0;
+                for(String schema: sSchemaActionResMap.keySet()) {
+                    if(urls[0].getURL().indexOf(schema) >= 0) {
+                        defaultResId = sSchemaActionResMap.get(schema);
+                        break;
+                    }
+                }
+
+                if (defaultResId == 0) {
+                    defaultResId = R.string.note_link_other;
+                }
+
+                menu.add(0, 0, 0, defaultResId).setOnMenuItemClickListener(
+                        new OnMenuItemClickListener() {
+                            public boolean onMenuItemClick(MenuItem item) {
+                                // goto a new intent
+                                urls[0].onClick(NoteEditText.this);
+                                return true;
+                            }
+                        });
+            }
+        }
+        super.onCreateContextMenu(menu);
+    }
+}

java/net/micode/notes/ui/NoteItemData.java

@@ -0,0 +1,264 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了NoteItemData类，主要用于对从数据库查询获取的笔记相关数据（通过Cursor传递）进行解析和封装，提取出如笔记ID、提醒日期、背景颜色ID等各种具体的信息，并根据数据情况判断笔记在列表中的位置关系（是否是首个、最后一个、唯一的等）以及是否跟随文件夹等特殊情况，同时向外提供了一系列获取这些封装好的数据和状态判断结果的方法，方便在展示笔记相关列表或者进行其他与笔记数据交互的场景中使用。
+函数分析
+构造函数
+NoteItemData(Context context, Cursor cursor)：
+所属类：NoteItemData
+功能：
+从传入的Cursor中按照预定义的列索引（如ID_COLUMN等常量对应各字段位置）提取笔记各项数据，比如通过cursor.getLong、cursor.getInt、cursor.getString等方法分别获取对应类型的数据，并赋值给类中的成员变量（如mId、mBgColorId、mSnippet等），以此完成基础的数据解析和封装。
+针对笔记内容片段（mSnippet），会进行一些字符串替换操作（去掉特定的标记，像NoteEditActivity.TAG_CHECKED和NoteEditActivity.TAG_UNCHECKED）。
+当笔记的父ID是通话记录文件夹的ID（Notes.ID_CALL_RECORD_FOLDER）时，通过DataUtils.getCallNumberByNoteId方法尝试获取电话号码，若电话号码不为空，则利用Contact.getContact方法根据电话号码获取联系人姓名，若获取失败则将电话号码作为姓名，若电话号码本身为空则将姓名设为空字符串，完成与联系人相关信息的处理。
+最后调用checkPostion方法，根据Cursor的相关状态（如是否是首条、末条记录等）以及笔记类型等情况，判断笔记在列表中的位置相关属性（如是否是最后一个、第一个、唯一的，是否跟随文件夹等情况）并设置对应的成员变量（mIsLastItem、mIsFirstItem等）。
+位置判断相关函数
+checkPostion(Cursor cursor)：
+所属类：NoteItemData
+功能：
+首先判断Cursor当前是否处于最后一条记录，将结果赋值给mIsLastItem；判断是否处于第一条记录，赋值给mIsFirstItem；判断记录总数是否为1，来确定是否只有一个笔记项，赋值给mIsOnlyOneItem，并初始化mIsMultiNotesFollowingFolder和mIsOneNoteFollowingFolder为false。
+接着，如果笔记类型是普通笔记类型（mType == Notes.TYPE_NOTE）且不是第一条记录，获取当前Cursor的位置，尝试将Cursor移动到上一条记录，然后判断上一条记录的类型是否是文件夹类型或者系统类型，如果是，再判断总记录数是否大于当前位置加1，若是则表示有多条笔记跟随该文件夹，将mIsMultiNotesFollowingFolder设为true，否则设为mIsOneNoteFollowingFolder设为true，最后将Cursor移回原来位置（通过moveToNext方法，如果移不回则抛出异常），以此完成对笔记与文件夹关联位置关系的判断。
+状态获取相关函数
+isOneFollowingFolder()：
+所属类：NoteItemData
+功能：返回mIsOneNoteFollowingFolder的值，用于判断当前笔记是否是跟随文件夹的唯一一条笔记，外部代码可以通过调用这个方法知晓笔记的这种特殊位置关系情况。
+isMultiFollowingFolder()：
+所属类：NoteItemData
+功能：返回mIsMultiNotesFollowingFolder的值，用于判断当前笔记是否有多条笔记跟随所在的文件夹，方便外部代码根据这个结果进行不同的界面展示或者业务逻辑处理等。
+isLast()：
+所属类：NoteItemData
+功能：返回mIsLastItem的值，判断当前笔记是否是列表中的最后一项，在处理列表滚动、分页等相关逻辑时可能会用到这个判断结果。
+isFirst()：
+所属类：NoteItemData
+功能：返回mIsFirstItem的值，判断当前笔记是否是列表中的第一项，同样在一些涉及列表顺序相关的操作场景中会用到这个判断结果。
+isSingle()：
+所属类：NoteItemData
+功能：返回mIsOnlyOneItem的值，判断整个列表中是否只有当前这一个笔记项，对于一些特殊的界面显示或者数据处理逻辑（比如只有一个笔记时的特殊展示方式）可以依据这个结果来实现。
+数据获取相关函数
+getCallName()：
+所属类：NoteItemData
+功能：返回mName的值，即获取与笔记关联的联系人姓名（如果有），外部代码可以利用这个方法来展示笔记对应的联系人相关信息，比如在通话记录笔记展示中显示来电人姓名等场景。
+getId()、getAlertDate()、getCreatedDate()、getModifiedDate()、getBgColorId()、getParentId()、getNotesCount()、getFolderId()、getType()、getWidgetType()、getWidgetId()、getSnippet()：
+所属类：NoteItemData
+功能：这些函数分别返回对应成员变量（如mId、mAlertDate等）的值，方便外部代码获取笔记的各项具体数据，例如获取笔记ID用于数据关联、获取提醒日期用于展示提醒相关信息、获取片段内容用于在列表中展示笔记的简要内容等
+ */
+
+package net.micode.notes.ui;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.text.TextUtils;
+
+import net.micode.notes.data.Contact;
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.tool.DataUtils;
+
+
+public class NoteItemData {
+    static final String [] PROJECTION = new String [] {
+        NoteColumns.ID,
+        NoteColumns.ALERTED_DATE,
+        NoteColumns.BG_COLOR_ID,
+        NoteColumns.CREATED_DATE,
+        NoteColumns.HAS_ATTACHMENT,
+        NoteColumns.MODIFIED_DATE,
+        NoteColumns.NOTES_COUNT,
+        NoteColumns.PARENT_ID,
+        NoteColumns.SNIPPET,
+        NoteColumns.TYPE,
+        NoteColumns.WIDGET_ID,
+        NoteColumns.WIDGET_TYPE,
+    };
+
+    private static final int ID_COLUMN                    = 0;
+    private static final int ALERTED_DATE_COLUMN          = 1;
+    private static final int BG_COLOR_ID_COLUMN           = 2;
+    private static final int CREATED_DATE_COLUMN          = 3;
+    private static final int HAS_ATTACHMENT_COLUMN        = 4;
+    private static final int MODIFIED_DATE_COLUMN         = 5;
+    private static final int NOTES_COUNT_COLUMN           = 6;
+    private static final int PARENT_ID_COLUMN             = 7;
+    private static final int SNIPPET_COLUMN               = 8;
+    private static final int TYPE_COLUMN                  = 9;
+    private static final int WIDGET_ID_COLUMN             = 10;
+    private static final int WIDGET_TYPE_COLUMN           = 11;
+
+    private long mId;
+    private long mAlertDate;
+    private int mBgColorId;
+    private long mCreatedDate;
+    private boolean mHasAttachment;
+    private long mModifiedDate;
+    private int mNotesCount;
+    private long mParentId;
+    private String mSnippet;
+    private int mType;
+    private int mWidgetId;
+    private int mWidgetType;
+    private String mName;
+    private String mPhoneNumber;
+
+    private boolean mIsLastItem;
+    private boolean mIsFirstItem;
+    private boolean mIsOnlyOneItem;
+    private boolean mIsOneNoteFollowingFolder;
+    private boolean mIsMultiNotesFollowingFolder;
+
+    public NoteItemData(Context context, Cursor cursor) {
+        mId = cursor.getLong(ID_COLUMN);
+        mAlertDate = cursor.getLong(ALERTED_DATE_COLUMN);
+        mBgColorId = cursor.getInt(BG_COLOR_ID_COLUMN);
+        mCreatedDate = cursor.getLong(CREATED_DATE_COLUMN);
+        mHasAttachment = (cursor.getInt(HAS_ATTACHMENT_COLUMN) > 0) ? true : false;
+        mModifiedDate = cursor.getLong(MODIFIED_DATE_COLUMN);
+        mNotesCount = cursor.getInt(NOTES_COUNT_COLUMN);
+        mParentId = cursor.getLong(PARENT_ID_COLUMN);
+        mSnippet = cursor.getString(SNIPPET_COLUMN);
+        mSnippet = mSnippet.replace(NoteEditActivity.TAG_CHECKED, "").replace(
+                NoteEditActivity.TAG_UNCHECKED, "");
+        mType = cursor.getInt(TYPE_COLUMN);
+        mWidgetId = cursor.getInt(WIDGET_ID_COLUMN);
+        mWidgetType = cursor.getInt(WIDGET_TYPE_COLUMN);
+
+        mPhoneNumber = "";
+        if (mParentId == Notes.ID_CALL_RECORD_FOLDER) {
+            mPhoneNumber = DataUtils.getCallNumberByNoteId(context.getContentResolver(), mId);
+            if (!TextUtils.isEmpty(mPhoneNumber)) {
+                mName = Contact.getContact(context, mPhoneNumber);
+                if (mName == null) {
+                    mName = mPhoneNumber;
+                }
+            }
+        }
+
+        if (mName == null) {
+            mName = "";
+        }
+        checkPostion(cursor);
+    }
+
+    private void checkPostion(Cursor cursor) {
+        mIsLastItem = cursor.isLast() ? true : false;
+        mIsFirstItem = cursor.isFirst() ? true : false;
+        mIsOnlyOneItem = (cursor.getCount() == 1);
+        mIsMultiNotesFollowingFolder = false;
+        mIsOneNoteFollowingFolder = false;
+
+        if (mType == Notes.TYPE_NOTE && !mIsFirstItem) {
+            int position = cursor.getPosition();
+            if (cursor.moveToPrevious()) {
+                if (cursor.getInt(TYPE_COLUMN) == Notes.TYPE_FOLDER
+                        || cursor.getInt(TYPE_COLUMN) == Notes.TYPE_SYSTEM) {
+                    if (cursor.getCount() > (position + 1)) {
+                        mIsMultiNotesFollowingFolder = true;
+                    } else {
+                        mIsOneNoteFollowingFolder = true;
+                    }
+                }
+                if (!cursor.moveToNext()) {
+                    throw new IllegalStateException("cursor move to previous but can't move back");
+                }
+            }
+        }
+    }
+
+    public boolean isOneFollowingFolder() {
+        return mIsOneNoteFollowingFolder;
+    }
+
+    public boolean isMultiFollowingFolder() {
+        return mIsMultiNotesFollowingFolder;
+    }
+
+    public boolean isLast() {
+        return mIsLastItem;
+    }
+
+    public String getCallName() {
+        return mName;
+    }
+
+    public boolean isFirst() {
+        return mIsFirstItem;
+    }
+
+    public boolean isSingle() {
+        return mIsOnlyOneItem;
+    }
+
+    public long getId() {
+        return mId;
+    }
+
+    public long getAlertDate() {
+        return mAlertDate;
+    }
+
+    public long getCreatedDate() {
+        return mCreatedDate;
+    }
+
+    public boolean hasAttachment() {
+        return mHasAttachment;
+    }
+
+    public long getModifiedDate() {
+        return mModifiedDate;
+    }
+
+    public int getBgColorId() {
+        return mBgColorId;
+    }
+
+    public long getParentId() {
+        return mParentId;
+    }
+
+    public int getNotesCount() {
+        return mNotesCount;
+    }
+
+    public long getFolderId () {
+        return mParentId;
+    }
+
+    public int getType() {
+        return mType;
+    }
+
+    public int getWidgetType() {
+        return mWidgetType;
+    }
+
+    public int getWidgetId() {
+        return mWidgetId;
+    }
+
+    public String getSnippet() {
+        return mSnippet;
+    }
+
+    public boolean hasAlert() {
+        return (mAlertDate > 0);
+    }
+
+    public boolean isCallRecord() {
+        return (mParentId == Notes.ID_CALL_RECORD_FOLDER && !TextUtils.isEmpty(mPhoneNumber));
+    }
+
+    public static int getNoteType(Cursor cursor) {
+        return cursor.getInt(TYPE_COLUMN);
+    }
+}

java/net/micode/notes/ui/NotesListActivity.java

@@ -0,0 +1,954 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.ui;
+
+import android.app.Activity;
+import android.app.AlertDialog;
+import android.app.Dialog;
+import android.appwidget.AppWidgetManager;
+import android.content.AsyncQueryHandler;
+import android.content.ContentResolver;
+import android.content.ContentValues;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.content.SharedPreferences;
+import android.database.Cursor;
+import android.os.AsyncTask;
+import android.os.Bundle;
+import android.preference.PreferenceManager;
+import android.text.Editable;
+import android.text.TextUtils;
+import android.text.TextWatcher;
+import android.util.Log;
+import android.view.ActionMode;
+import android.view.ContextMenu;
+import android.view.ContextMenu.ContextMenuInfo;
+import android.view.Display;
+import android.view.HapticFeedbackConstants;
+import android.view.LayoutInflater;
+import android.view.Menu;
+import android.view.MenuItem;
+import android.view.MenuItem.OnMenuItemClickListener;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.View.OnClickListener;
+import android.view.View.OnCreateContextMenuListener;
+import android.view.View.OnTouchListener;
+import android.view.inputmethod.InputMethodManager;
+import android.widget.AdapterView;
+import android.widget.AdapterView.OnItemClickListener;
+import android.widget.AdapterView.OnItemLongClickListener;
+import android.widget.Button;
+import android.widget.EditText;
+import android.widget.ListView;
+import android.widget.PopupMenu;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.gtask.remote.GTaskSyncService;
+import net.micode.notes.model.WorkingNote;
+import net.micode.notes.tool.BackupUtils;
+import net.micode.notes.tool.DataUtils;
+import net.micode.notes.tool.ResourceParser;
+import net.micode.notes.ui.NotesListAdapter.AppWidgetAttribute;
+import net.micode.notes.widget.NoteWidgetProvider_2x;
+import net.micode.notes.widget.NoteWidgetProvider_4x;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.HashSet;
+
+public class NotesListActivity extends Activity implements OnClickListener, OnItemLongClickListener {
+    private static final int FOLDER_NOTE_LIST_QUERY_TOKEN = 0;
+
+    private static final int FOLDER_LIST_QUERY_TOKEN      = 1;
+
+    private static final int MENU_FOLDER_DELETE = 0;
+
+    private static final int MENU_FOLDER_VIEW = 1;
+
+    private static final int MENU_FOLDER_CHANGE_NAME = 2;
+
+    private static final String PREFERENCE_ADD_INTRODUCTION = "net.micode.notes.introduction";
+
+    private enum ListEditState {
+        NOTE_LIST, SUB_FOLDER, CALL_RECORD_FOLDER
+    };
+
+    private ListEditState mState;
+
+    private BackgroundQueryHandler mBackgroundQueryHandler;
+
+    private NotesListAdapter mNotesListAdapter;
+
+    private ListView mNotesListView;
+
+    private Button mAddNewNote;
+
+    private boolean mDispatch;
+
+    private int mOriginY;
+
+    private int mDispatchY;
+
+    private TextView mTitleBar;
+
+    private long mCurrentFolderId;
+
+    private ContentResolver mContentResolver;
+
+    private ModeCallback mModeCallBack;
+
+    private static final String TAG = "NotesListActivity";
+
+    public static final int NOTES_LISTVIEW_SCROLL_RATE = 30;
+
+    private NoteItemData mFocusNoteDataItem;
+
+    private static final String NORMAL_SELECTION = NoteColumns.PARENT_ID + "=?";
+
+    private static final String ROOT_FOLDER_SELECTION = "(" + NoteColumns.TYPE + "<>"
+            + Notes.TYPE_SYSTEM + " AND " + NoteColumns.PARENT_ID + "=?)" + " OR ("
+            + NoteColumns.ID + "=" + Notes.ID_CALL_RECORD_FOLDER + " AND "
+            + NoteColumns.NOTES_COUNT + ">0)";
+
+    private final static int REQUEST_CODE_OPEN_NODE = 102;
+    private final static int REQUEST_CODE_NEW_NODE  = 103;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.note_list);
+        initResources();
+
+        /**
+         * Insert an introduction when user firstly use this application
+         */
+        setAppInfoFromRawRes();
+    }
+
+    @Override
+    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
+        if (resultCode == RESULT_OK
+                && (requestCode == REQUEST_CODE_OPEN_NODE || requestCode == REQUEST_CODE_NEW_NODE)) {
+            mNotesListAdapter.changeCursor(null);
+        } else {
+            super.onActivityResult(requestCode, resultCode, data);
+        }
+    }
+
+    private void setAppInfoFromRawRes() {
+        SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
+        if (!sp.getBoolean(PREFERENCE_ADD_INTRODUCTION, false)) {
+            StringBuilder sb = new StringBuilder();
+            InputStream in = null;
+            try {
+                 in = getResources().openRawResource(R.raw.introduction);
+                if (in != null) {
+                    InputStreamReader isr = new InputStreamReader(in);
+                    BufferedReader br = new BufferedReader(isr);
+                    char [] buf = new char[1024];
+                    int len = 0;
+                    while ((len = br.read(buf)) > 0) {
+                        sb.append(buf, 0, len);
+                    }
+                } else {
+                    Log.e(TAG, "Read introduction file error");
+                    return;
+                }
+            } catch (IOException e) {
+                e.printStackTrace();
+                return;
+            } finally {
+                if(in != null) {
+                    try {
+                        in.close();
+                    } catch (IOException e) {
+                        // TODO Auto-generated catch block
+                        e.printStackTrace();
+                    }
+                }
+            }
+
+            WorkingNote note = WorkingNote.createEmptyNote(this, Notes.ID_ROOT_FOLDER,
+                    AppWidgetManager.INVALID_APPWIDGET_ID, Notes.TYPE_WIDGET_INVALIDE,
+                    ResourceParser.RED);
+            note.setWorkingText(sb.toString());
+            if (note.saveNote()) {
+                sp.edit().putBoolean(PREFERENCE_ADD_INTRODUCTION, true).commit();
+            } else {
+                Log.e(TAG, "Save introduction note error");
+                return;
+            }
+        }
+    }
+
+    @Override
+    protected void onStart() {
+        super.onStart();
+        startAsyncNotesListQuery();
+    }
+
+    private void initResources() {
+        mContentResolver = this.getContentResolver();
+        mBackgroundQueryHandler = new BackgroundQueryHandler(this.getContentResolver());
+        mCurrentFolderId = Notes.ID_ROOT_FOLDER;
+        mNotesListView = (ListView) findViewById(R.id.notes_list);
+        mNotesListView.addFooterView(LayoutInflater.from(this).inflate(R.layout.note_list_footer, null),
+                null, false);
+        mNotesListView.setOnItemClickListener(new OnListItemClickListener());
+        mNotesListView.setOnItemLongClickListener(this);
+        mNotesListAdapter = new NotesListAdapter(this);
+        mNotesListView.setAdapter(mNotesListAdapter);
+        mAddNewNote = (Button) findViewById(R.id.btn_new_note);
+        mAddNewNote.setOnClickListener(this);
+        mAddNewNote.setOnTouchListener(new NewNoteOnTouchListener());
+        mDispatch = false;
+        mDispatchY = 0;
+        mOriginY = 0;
+        mTitleBar = (TextView) findViewById(R.id.tv_title_bar);
+        mState = ListEditState.NOTE_LIST;
+        mModeCallBack = new ModeCallback();
+    }
+
+    private class ModeCallback implements ListView.MultiChoiceModeListener, OnMenuItemClickListener {
+        private DropdownMenu mDropDownMenu;
+        private ActionMode mActionMode;
+        private MenuItem mMoveMenu;
+
+        public boolean onCreateActionMode(ActionMode mode, Menu menu) {
+            getMenuInflater().inflate(R.menu.note_list_options, menu);
+            menu.findItem(R.id.delete).setOnMenuItemClickListener(this);
+            mMoveMenu = menu.findItem(R.id.move);
+            if (mFocusNoteDataItem.getParentId() == Notes.ID_CALL_RECORD_FOLDER
+                    || DataUtils.getUserFolderCount(mContentResolver) == 0) {
+                mMoveMenu.setVisible(false);
+            } else {
+                mMoveMenu.setVisible(true);
+                mMoveMenu.setOnMenuItemClickListener(this);
+            }
+            mActionMode = mode;
+            mNotesListAdapter.setChoiceMode(true);
+            mNotesListView.setLongClickable(false);
+            mAddNewNote.setVisibility(View.GONE);
+
+            View customView = LayoutInflater.from(NotesListActivity.this).inflate(
+                    R.layout.note_list_dropdown_menu, null);
+            mode.setCustomView(customView);
+            mDropDownMenu = new DropdownMenu(NotesListActivity.this,
+                    (Button) customView.findViewById(R.id.selection_menu),
+                    R.menu.note_list_dropdown);
+            mDropDownMenu.setOnDropdownMenuItemClickListener(new PopupMenu.OnMenuItemClickListener(){
+                public boolean onMenuItemClick(MenuItem item) {
+                    mNotesListAdapter.selectAll(!mNotesListAdapter.isAllSelected());
+                    updateMenu();
+                    return true;
+                }
+
+            });
+            return true;
+        }
+
+        private void updateMenu() {
+            int selectedCount = mNotesListAdapter.getSelectedCount();
+            // Update dropdown menu
+            String format = getResources().getString(R.string.menu_select_title, selectedCount);
+            mDropDownMenu.setTitle(format);
+            MenuItem item = mDropDownMenu.findItem(R.id.action_select_all);
+            if (item != null) {
+                if (mNotesListAdapter.isAllSelected()) {
+                    item.setChecked(true);
+                    item.setTitle(R.string.menu_deselect_all);
+                } else {
+                    item.setChecked(false);
+                    item.setTitle(R.string.menu_select_all);
+                }
+            }
+        }
+
+        public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
+            // TODO Auto-generated method stub
+            return false;
+        }
+
+        public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
+            // TODO Auto-generated method stub
+            return false;
+        }
+
+        public void onDestroyActionMode(ActionMode mode) {
+            mNotesListAdapter.setChoiceMode(false);
+            mNotesListView.setLongClickable(true);
+            mAddNewNote.setVisibility(View.VISIBLE);
+        }
+
+        public void finishActionMode() {
+            mActionMode.finish();
+        }
+
+        public void onItemCheckedStateChanged(ActionMode mode, int position, long id,
+                boolean checked) {
+            mNotesListAdapter.setCheckedItem(position, checked);
+            updateMenu();
+        }
+
+        public boolean onMenuItemClick(MenuItem item) {
+            if (mNotesListAdapter.getSelectedCount() == 0) {
+                Toast.makeText(NotesListActivity.this, getString(R.string.menu_select_none),
+                        Toast.LENGTH_SHORT).show();
+                return true;
+            }
+
+            switch (item.getItemId()) {
+                case R.id.delete:
+                    AlertDialog.Builder builder = new AlertDialog.Builder(NotesListActivity.this);
+                    builder.setTitle(getString(R.string.alert_title_delete));
+                    builder.setIcon(android.R.drawable.ic_dialog_alert);
+                    builder.setMessage(getString(R.string.alert_message_delete_notes,
+                                             mNotesListAdapter.getSelectedCount()));
+                    builder.setPositiveButton(android.R.string.ok,
+                                             new DialogInterface.OnClickListener() {
+                                                 public void onClick(DialogInterface dialog,
+                                                         int which) {
+                                                     batchDelete();
+                                                 }
+                                             });
+                    builder.setNegativeButton(android.R.string.cancel, null);
+                    builder.show();
+                    break;
+                case R.id.move:
+                    startQueryDestinationFolders();
+                    break;
+                default:
+                    return false;
+            }
+            return true;
+        }
+    }
+
+    private class NewNoteOnTouchListener implements OnTouchListener {
+
+        public boolean onTouch(View v, MotionEvent event) {
+            switch (event.getAction()) {
+                case MotionEvent.ACTION_DOWN: {
+                    Display display = getWindowManager().getDefaultDisplay();
+                    int screenHeight = display.getHeight();
+                    int newNoteViewHeight = mAddNewNote.getHeight();
+                    int start = screenHeight - newNoteViewHeight;
+                    int eventY = start + (int) event.getY();
+                    /**
+                     * Minus TitleBar's height
+                     */
+                    if (mState == ListEditState.SUB_FOLDER) {
+                        eventY -= mTitleBar.getHeight();
+                        start -= mTitleBar.getHeight();
+                    }
+                    /**
+                     * HACKME:When click the transparent part of "New Note" button, dispatch
+                     * the event to the list view behind this button. The transparent part of
+                     * "New Note" button could be expressed by formula y=-0.12x+94（Unit:pixel）
+                     * and the line top of the button. The coordinate based on left of the "New
+                     * Note" button. The 94 represents maximum height of the transparent part.
+                     * Notice that, if the background of the button changes, the formula should
+                     * also change. This is very bad, just for the UI designer's strong requirement.
+                     */
+                    if (event.getY() < (event.getX() * (-0.12) + 94)) {
+                        View view = mNotesListView.getChildAt(mNotesListView.getChildCount() - 1
+                                - mNotesListView.getFooterViewsCount());
+                        if (view != null && view.getBottom() > start
+                                && (view.getTop() < (start + 94))) {
+                            mOriginY = (int) event.getY();
+                            mDispatchY = eventY;
+                            event.setLocation(event.getX(), mDispatchY);
+                            mDispatch = true;
+                            return mNotesListView.dispatchTouchEvent(event);
+                        }
+                    }
+                    break;
+                }
+                case MotionEvent.ACTION_MOVE: {
+                    if (mDispatch) {
+                        mDispatchY += (int) event.getY() - mOriginY;
+                        event.setLocation(event.getX(), mDispatchY);
+                        return mNotesListView.dispatchTouchEvent(event);
+                    }
+                    break;
+                }
+                default: {
+                    if (mDispatch) {
+                        event.setLocation(event.getX(), mDispatchY);
+                        mDispatch = false;
+                        return mNotesListView.dispatchTouchEvent(event);
+                    }
+                    break;
+                }
+            }
+            return false;
+        }
+
+    };
+
+    private void startAsyncNotesListQuery() {
+        String selection = (mCurrentFolderId == Notes.ID_ROOT_FOLDER) ? ROOT_FOLDER_SELECTION
+                : NORMAL_SELECTION;
+        mBackgroundQueryHandler.startQuery(FOLDER_NOTE_LIST_QUERY_TOKEN, null,
+                Notes.CONTENT_NOTE_URI, NoteItemData.PROJECTION, selection, new String[] {
+                    String.valueOf(mCurrentFolderId)
+                }, NoteColumns.TYPE + " DESC," + NoteColumns.MODIFIED_DATE + " DESC");
+    }
+
+    private final class BackgroundQueryHandler extends AsyncQueryHandler {
+        public BackgroundQueryHandler(ContentResolver contentResolver) {
+            super(contentResolver);
+        }
+
+        @Override
+        protected void onQueryComplete(int token, Object cookie, Cursor cursor) {
+            switch (token) {
+                case FOLDER_NOTE_LIST_QUERY_TOKEN:
+                    mNotesListAdapter.changeCursor(cursor);
+                    break;
+                case FOLDER_LIST_QUERY_TOKEN:
+                    if (cursor != null && cursor.getCount() > 0) {
+                        showFolderListMenu(cursor);
+                    } else {
+                        Log.e(TAG, "Query folder failed");
+                    }
+                    break;
+                default:
+                    return;
+            }
+        }
+    }
+
+    private void showFolderListMenu(Cursor cursor) {
+        AlertDialog.Builder builder = new AlertDialog.Builder(NotesListActivity.this);
+        builder.setTitle(R.string.menu_title_select_folder);
+        final FoldersListAdapter adapter = new FoldersListAdapter(this, cursor);
+        builder.setAdapter(adapter, new DialogInterface.OnClickListener() {
+
+            public void onClick(DialogInterface dialog, int which) {
+                DataUtils.batchMoveToFolder(mContentResolver,
+                        mNotesListAdapter.getSelectedItemIds(), adapter.getItemId(which));
+                Toast.makeText(
+                        NotesListActivity.this,
+                        getString(R.string.format_move_notes_to_folder,
+                                mNotesListAdapter.getSelectedCount(),
+                                adapter.getFolderName(NotesListActivity.this, which)),
+                        Toast.LENGTH_SHORT).show();
+                mModeCallBack.finishActionMode();
+            }
+        });
+        builder.show();
+    }
+
+    private void createNewNote() {
+        Intent intent = new Intent(this, NoteEditActivity.class);
+        intent.setAction(Intent.ACTION_INSERT_OR_EDIT);
+        intent.putExtra(Notes.INTENT_EXTRA_FOLDER_ID, mCurrentFolderId);
+        this.startActivityForResult(intent, REQUEST_CODE_NEW_NODE);
+    }
+
+    private void batchDelete() {
+        new AsyncTask<Void, Void, HashSet<AppWidgetAttribute>>() {
+            protected HashSet<AppWidgetAttribute> doInBackground(Void... unused) {
+                HashSet<AppWidgetAttribute> widgets = mNotesListAdapter.getSelectedWidget();
+                if (!isSyncMode()) {
+                    // if not synced, delete notes directly
+                    if (DataUtils.batchDeleteNotes(mContentResolver, mNotesListAdapter
+                            .getSelectedItemIds())) {
+                    } else {
+                        Log.e(TAG, "Delete notes error, should not happens");
+                    }
+                } else {
+                    // in sync mode, we'll move the deleted note into the trash
+                    // folder
+                    if (!DataUtils.batchMoveToFolder(mContentResolver, mNotesListAdapter
+                            .getSelectedItemIds(), Notes.ID_TRASH_FOLER)) {
+                        Log.e(TAG, "Move notes to trash folder error, should not happens");
+                    }
+                }
+                return widgets;
+            }
+
+            @Override
+            protected void onPostExecute(HashSet<AppWidgetAttribute> widgets) {
+                if (widgets != null) {
+                    for (AppWidgetAttribute widget : widgets) {
+                        if (widget.widgetId != AppWidgetManager.INVALID_APPWIDGET_ID
+                                && widget.widgetType != Notes.TYPE_WIDGET_INVALIDE) {
+                            updateWidget(widget.widgetId, widget.widgetType);
+                        }
+                    }
+                }
+                mModeCallBack.finishActionMode();
+            }
+        }.execute();
+    }
+
+    private void deleteFolder(long folderId) {
+        if (folderId == Notes.ID_ROOT_FOLDER) {
+            Log.e(TAG, "Wrong folder id, should not happen " + folderId);
+            return;
+        }
+
+        HashSet<Long> ids = new HashSet<Long>();
+        ids.add(folderId);
+        HashSet<AppWidgetAttribute> widgets = DataUtils.getFolderNoteWidget(mContentResolver,
+                folderId);
+        if (!isSyncMode()) {
+            // if not synced, delete folder directly
+            DataUtils.batchDeleteNotes(mContentResolver, ids);
+        } else {
+            // in sync mode, we'll move the deleted folder into the trash folder
+            DataUtils.batchMoveToFolder(mContentResolver, ids, Notes.ID_TRASH_FOLER);
+        }
+        if (widgets != null) {
+            for (AppWidgetAttribute widget : widgets) {
+                if (widget.widgetId != AppWidgetManager.INVALID_APPWIDGET_ID
+                        && widget.widgetType != Notes.TYPE_WIDGET_INVALIDE) {
+                    updateWidget(widget.widgetId, widget.widgetType);
+                }
+            }
+        }
+    }
+
+    private void openNode(NoteItemData data) {
+        Intent intent = new Intent(this, NoteEditActivity.class);
+        intent.setAction(Intent.ACTION_VIEW);
+        intent.putExtra(Intent.EXTRA_UID, data.getId());
+        this.startActivityForResult(intent, REQUEST_CODE_OPEN_NODE);
+    }
+
+    private void openFolder(NoteItemData data) {
+        mCurrentFolderId = data.getId();
+        startAsyncNotesListQuery();
+        if (data.getId() == Notes.ID_CALL_RECORD_FOLDER) {
+            mState = ListEditState.CALL_RECORD_FOLDER;
+            mAddNewNote.setVisibility(View.GONE);
+        } else {
+            mState = ListEditState.SUB_FOLDER;
+        }
+        if (data.getId() == Notes.ID_CALL_RECORD_FOLDER) {
+            mTitleBar.setText(R.string.call_record_folder_name);
+        } else {
+            mTitleBar.setText(data.getSnippet());
+        }
+        mTitleBar.setVisibility(View.VISIBLE);
+    }
+
+    public void onClick(View v) {
+        switch (v.getId()) {
+            case R.id.btn_new_note:
+                createNewNote();
+                break;
+            default:
+                break;
+        }
+    }
+
+    private void showSoftInput() {
+        InputMethodManager inputMethodManager = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
+        if (inputMethodManager != null) {
+            inputMethodManager.toggleSoftInput(InputMethodManager.SHOW_FORCED, 0);
+        }
+    }
+
+    private void hideSoftInput(View view) {
+        InputMethodManager inputMethodManager = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
+        inputMethodManager.hideSoftInputFromWindow(view.getWindowToken(), 0);
+    }
+
+    private void showCreateOrModifyFolderDialog(final boolean create) {
+        final AlertDialog.Builder builder = new AlertDialog.Builder(this);
+        View view = LayoutInflater.from(this).inflate(R.layout.dialog_edit_text, null);
+        final EditText etName = (EditText) view.findViewById(R.id.et_foler_name);
+        showSoftInput();
+        if (!create) {
+            if (mFocusNoteDataItem != null) {
+                etName.setText(mFocusNoteDataItem.getSnippet());
+                builder.setTitle(getString(R.string.menu_folder_change_name));
+            } else {
+                Log.e(TAG, "The long click data item is null");
+                return;
+            }
+        } else {
+            etName.setText("");
+            builder.setTitle(this.getString(R.string.menu_create_folder));
+        }
+
+        builder.setPositiveButton(android.R.string.ok, null);
+        builder.setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
+            public void onClick(DialogInterface dialog, int which) {
+                hideSoftInput(etName);
+            }
+        });
+
+        final Dialog dialog = builder.setView(view).show();
+        final Button positive = (Button)dialog.findViewById(android.R.id.button1);
+        positive.setOnClickListener(new OnClickListener() {
+            public void onClick(View v) {
+                hideSoftInput(etName);
+                String name = etName.getText().toString();
+                if (DataUtils.checkVisibleFolderName(mContentResolver, name)) {
+                    Toast.makeText(NotesListActivity.this, getString(R.string.folder_exist, name),
+                            Toast.LENGTH_LONG).show();
+                    etName.setSelection(0, etName.length());
+                    return;
+                }
+                if (!create) {
+                    if (!TextUtils.isEmpty(name)) {
+                        ContentValues values = new ContentValues();
+                        values.put(NoteColumns.SNIPPET, name);
+                        values.put(NoteColumns.TYPE, Notes.TYPE_FOLDER);
+                        values.put(NoteColumns.LOCAL_MODIFIED, 1);
+                        mContentResolver.update(Notes.CONTENT_NOTE_URI, values, NoteColumns.ID
+                                + "=?", new String[] {
+                            String.valueOf(mFocusNoteDataItem.getId())
+                        });
+                    }
+                } else if (!TextUtils.isEmpty(name)) {
+                    ContentValues values = new ContentValues();
+                    values.put(NoteColumns.SNIPPET, name);
+                    values.put(NoteColumns.TYPE, Notes.TYPE_FOLDER);
+                    mContentResolver.insert(Notes.CONTENT_NOTE_URI, values);
+                }
+                dialog.dismiss();
+            }
+        });
+
+        if (TextUtils.isEmpty(etName.getText())) {
+            positive.setEnabled(false);
+        }
+        /**
+         * When the name edit text is null, disable the positive button
+         */
+        etName.addTextChangedListener(new TextWatcher() {
+            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
+                // TODO Auto-generated method stub
+
+            }
+
+            public void onTextChanged(CharSequence s, int start, int before, int count) {
+                if (TextUtils.isEmpty(etName.getText())) {
+                    positive.setEnabled(false);
+                } else {
+                    positive.setEnabled(true);
+                }
+            }
+
+            public void afterTextChanged(Editable s) {
+                // TODO Auto-generated method stub
+
+            }
+        });
+    }
+
+    @Override
+    public void onBackPressed() {
+        switch (mState) {
+            case SUB_FOLDER:
+                mCurrentFolderId = Notes.ID_ROOT_FOLDER;
+                mState = ListEditState.NOTE_LIST;
+                startAsyncNotesListQuery();
+                mTitleBar.setVisibility(View.GONE);
+                break;
+            case CALL_RECORD_FOLDER:
+                mCurrentFolderId = Notes.ID_ROOT_FOLDER;
+                mState = ListEditState.NOTE_LIST;
+                mAddNewNote.setVisibility(View.VISIBLE);
+                mTitleBar.setVisibility(View.GONE);
+                startAsyncNotesListQuery();
+                break;
+            case NOTE_LIST:
+                super.onBackPressed();
+                break;
+            default:
+                break;
+        }
+    }
+
+    private void updateWidget(int appWidgetId, int appWidgetType) {
+        Intent intent = new Intent(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
+        if (appWidgetType == Notes.TYPE_WIDGET_2X) {
+            intent.setClass(this, NoteWidgetProvider_2x.class);
+        } else if (appWidgetType == Notes.TYPE_WIDGET_4X) {
+            intent.setClass(this, NoteWidgetProvider_4x.class);
+        } else {
+            Log.e(TAG, "Unspported widget type");
+            return;
+        }
+
+        intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS, new int[] {
+            appWidgetId
+        });
+
+        sendBroadcast(intent);
+        setResult(RESULT_OK, intent);
+    }
+
+    private final OnCreateContextMenuListener mFolderOnCreateContextMenuListener = new OnCreateContextMenuListener() {
+        public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
+            if (mFocusNoteDataItem != null) {
+                menu.setHeaderTitle(mFocusNoteDataItem.getSnippet());
+                menu.add(0, MENU_FOLDER_VIEW, 0, R.string.menu_folder_view);
+                menu.add(0, MENU_FOLDER_DELETE, 0, R.string.menu_folder_delete);
+                menu.add(0, MENU_FOLDER_CHANGE_NAME, 0, R.string.menu_folder_change_name);
+            }
+        }
+    };
+
+    @Override
+    public void onContextMenuClosed(Menu menu) {
+        if (mNotesListView != null) {
+            mNotesListView.setOnCreateContextMenuListener(null);
+        }
+        super.onContextMenuClosed(menu);
+    }
+
+    @Override
+    public boolean onContextItemSelected(MenuItem item) {
+        if (mFocusNoteDataItem == null) {
+            Log.e(TAG, "The long click data item is null");
+            return false;
+        }
+        switch (item.getItemId()) {
+            case MENU_FOLDER_VIEW:
+                openFolder(mFocusNoteDataItem);
+                break;
+            case MENU_FOLDER_DELETE:
+                AlertDialog.Builder builder = new AlertDialog.Builder(this);
+                builder.setTitle(getString(R.string.alert_title_delete));
+                builder.setIcon(android.R.drawable.ic_dialog_alert);
+                builder.setMessage(getString(R.string.alert_message_delete_folder));
+                builder.setPositiveButton(android.R.string.ok,
+                        new DialogInterface.OnClickListener() {
+                            public void onClick(DialogInterface dialog, int which) {
+                                deleteFolder(mFocusNoteDataItem.getId());
+                            }
+                        });
+                builder.setNegativeButton(android.R.string.cancel, null);
+                builder.show();
+                break;
+            case MENU_FOLDER_CHANGE_NAME:
+                showCreateOrModifyFolderDialog(false);
+                break;
+            default:
+                break;
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean onPrepareOptionsMenu(Menu menu) {
+        menu.clear();
+        if (mState == ListEditState.NOTE_LIST) {
+            getMenuInflater().inflate(R.menu.note_list, menu);
+            // set sync or sync_cancel
+            menu.findItem(R.id.menu_sync).setTitle(
+                    GTaskSyncService.isSyncing() ? R.string.menu_sync_cancel : R.string.menu_sync);
+        } else if (mState == ListEditState.SUB_FOLDER) {
+            getMenuInflater().inflate(R.menu.sub_folder, menu);
+        } else if (mState == ListEditState.CALL_RECORD_FOLDER) {
+            getMenuInflater().inflate(R.menu.call_record_folder, menu);
+        } else {
+            Log.e(TAG, "Wrong state:" + mState);
+        }
+        return true;
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        switch (item.getItemId()) {
+            case R.id.menu_new_folder: {
+                showCreateOrModifyFolderDialog(true);
+                break;
+            }
+            case R.id.menu_export_text: {
+                exportNoteToText();
+                break;
+            }
+            case R.id.menu_sync: {
+                if (isSyncMode()) {
+                    if (TextUtils.equals(item.getTitle(), getString(R.string.menu_sync))) {
+                        GTaskSyncService.startSync(this);
+                    } else {
+                        GTaskSyncService.cancelSync(this);
+                    }
+                } else {
+                    startPreferenceActivity();
+                }
+                break;
+            }
+            case R.id.menu_setting: {
+                startPreferenceActivity();
+                break;
+            }
+            case R.id.menu_new_note: {
+                createNewNote();
+                break;
+            }
+            case R.id.menu_search:
+                onSearchRequested();
+                break;
+            default:
+                break;
+        }
+        return true;
+    }
+
+    @Override
+    public boolean onSearchRequested() {
+        startSearch(null, false, null /* appData */, false);
+        return true;
+    }
+
+    private void exportNoteToText() {
+        final BackupUtils backup = BackupUtils.getInstance(NotesListActivity.this);
+        new AsyncTask<Void, Void, Integer>() {
+
+            @Override
+            protected Integer doInBackground(Void... unused) {
+                return backup.exportToText();
+            }
+
+            @Override
+            protected void onPostExecute(Integer result) {
+                if (result == BackupUtils.STATE_SD_CARD_UNMOUONTED) {
+                    AlertDialog.Builder builder = new AlertDialog.Builder(NotesListActivity.this);
+                    builder.setTitle(NotesListActivity.this
+                            .getString(R.string.failed_sdcard_export));
+                    builder.setMessage(NotesListActivity.this
+                            .getString(R.string.error_sdcard_unmounted));
+                    builder.setPositiveButton(android.R.string.ok, null);
+                    builder.show();
+                } else if (result == BackupUtils.STATE_SUCCESS) {
+                    AlertDialog.Builder builder = new AlertDialog.Builder(NotesListActivity.this);
+                    builder.setTitle(NotesListActivity.this
+                            .getString(R.string.success_sdcard_export));
+                    builder.setMessage(NotesListActivity.this.getString(
+                            R.string.format_exported_file_location, backup
+                                    .getExportedTextFileName(), backup.getExportedTextFileDir()));
+                    builder.setPositiveButton(android.R.string.ok, null);
+                    builder.show();
+                } else if (result == BackupUtils.STATE_SYSTEM_ERROR) {
+                    AlertDialog.Builder builder = new AlertDialog.Builder(NotesListActivity.this);
+                    builder.setTitle(NotesListActivity.this
+                            .getString(R.string.failed_sdcard_export));
+                    builder.setMessage(NotesListActivity.this
+                            .getString(R.string.error_sdcard_export));
+                    builder.setPositiveButton(android.R.string.ok, null);
+                    builder.show();
+                }
+            }
+
+        }.execute();
+    }
+
+    private boolean isSyncMode() {
+        return NotesPreferenceActivity.getSyncAccountName(this).trim().length() > 0;
+    }
+
+    private void startPreferenceActivity() {
+        Activity from = getParent() != null ? getParent() : this;
+        Intent intent = new Intent(from, NotesPreferenceActivity.class);
+        from.startActivityIfNeeded(intent, -1);
+    }
+
+    private class OnListItemClickListener implements OnItemClickListener {
+
+        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
+            if (view instanceof NotesListItem) {
+                NoteItemData item = ((NotesListItem) view).getItemData();
+                if (mNotesListAdapter.isInChoiceMode()) {
+                    if (item.getType() == Notes.TYPE_NOTE) {
+                        position = position - mNotesListView.getHeaderViewsCount();
+                        mModeCallBack.onItemCheckedStateChanged(null, position, id,
+                                !mNotesListAdapter.isSelectedItem(position));
+                    }
+                    return;
+                }
+
+                switch (mState) {
+                    case NOTE_LIST:
+                        if (item.getType() == Notes.TYPE_FOLDER
+                                || item.getType() == Notes.TYPE_SYSTEM) {
+                            openFolder(item);
+                        } else if (item.getType() == Notes.TYPE_NOTE) {
+                            openNode(item);
+                        } else {
+                            Log.e(TAG, "Wrong note type in NOTE_LIST");
+                        }
+                        break;
+                    case SUB_FOLDER:
+                    case CALL_RECORD_FOLDER:
+                        if (item.getType() == Notes.TYPE_NOTE) {
+                            openNode(item);
+                        } else {
+                            Log.e(TAG, "Wrong note type in SUB_FOLDER");
+                        }
+                        break;
+                    default:
+                        break;
+                }
+            }
+        }
+
+    }
+
+    private void startQueryDestinationFolders() {
+        String selection = NoteColumns.TYPE + "=? AND " + NoteColumns.PARENT_ID + "<>? AND " + NoteColumns.ID + "<>?";
+        selection = (mState == ListEditState.NOTE_LIST) ? selection:
+            "(" + selection + ") OR (" + NoteColumns.ID + "=" + Notes.ID_ROOT_FOLDER + ")";
+
+        mBackgroundQueryHandler.startQuery(FOLDER_LIST_QUERY_TOKEN,
+                null,
+                Notes.CONTENT_NOTE_URI,
+                FoldersListAdapter.PROJECTION,
+                selection,
+                new String[] {
+                        String.valueOf(Notes.TYPE_FOLDER),
+                        String.valueOf(Notes.ID_TRASH_FOLER),
+                        String.valueOf(mCurrentFolderId)
+                },
+                NoteColumns.MODIFIED_DATE + " DESC");
+    }
+
+    public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
+        if (view instanceof NotesListItem) {
+            mFocusNoteDataItem = ((NotesListItem) view).getItemData();
+            if (mFocusNoteDataItem.getType() == Notes.TYPE_NOTE && !mNotesListAdapter.isInChoiceMode()) {
+                if (mNotesListView.startActionMode(mModeCallBack) != null) {
+                    mModeCallBack.onItemCheckedStateChanged(null, position, id, true);
+                    mNotesListView.performHapticFeedback(HapticFeedbackConstants.LONG_PRESS);
+                } else {
+                    Log.e(TAG, "startActionMode fails");
+                }
+            } else if (mFocusNoteDataItem.getType() == Notes.TYPE_FOLDER) {
+                mNotesListView.setOnCreateContextMenuListener(mFolderOnCreateContextMenuListener);
+            }
+        }
+        return false;
+    }
+}

java/net/micode/notes/ui/NotesListAdapter.java

@@ -0,0 +1,212 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了NotesListAdapter类，它继承自CursorAdapter，主要用于在安卓应用中对笔记相关数据（以Cursor形式体现）进行适配，以便在列表等视图组件中展示相应的笔记信息，并实现了多项与笔记选择、统计相关的功能。例如支持设置选择模式、选中特定项、全选操作，能获取选中项的ID集合、选中的部件相关属性集合、选中的数量等信息，同时在数据内容变化或游标改变时会重新计算笔记数量，整体为处理笔记列表展示及选择操作提供了较为完善的功能支持。
+函数分析
+构造函数
+NotesListAdapter(Context context)：
+所属类：NotesListAdapter
+功能：
+首先调用父类（CursorAdapter）的构造函数并传入Context和null游标，进行基础的初始化。
+创建一个HashMap（mSelectedIndex）用于记录每个位置的笔记项是否被选中，将传入的Context赋值给mContext，并初始化笔记数量（mNotesCount）为0，为后续记录和处理笔记相关的选择状态及数量统计等操作做准备。
+视图创建相关函数
+newView(Context context, Cursor cursor, ViewGroup parent)：
+所属类：NotesListAdapter
+功能：重写了父类CursorAdapter的newView方法，用于创建一个新的视图对象来展示Cursor中的每一条数据记录。在这个方法中，它创建并返回了一个NotesListItem类的实例，意味着每一条笔记数据记录都会通过这个自定义的视图来展示，后续可以在这个自定义视图中进行具体的数据绑定和展示相关操作。
+视图数据绑定函数
+bindView(View view, Context context, Cursor cursor)：
+所属类：NotesListAdapter
+功能：重写了父类CursorAdapter的bindView方法，用于将Cursor中的数据绑定到对应的视图上进行展示。首先判断传入的视图是否是NotesListItem类型，如果是，则创建一个NoteItemData实例（通过传入Context和Cursor）来解析和封装当前笔记数据，然后调用((NotesListItem) view).bind方法，将Context、封装好的笔记数据（itemData）、选择模式（mChoiceMode）以及当前项是否被选中（通过isSelectedItem方法判断）等信息传递进去，在NotesListItem的bind方法中应该会根据这些信息来设置视图的具体显示内容，比如是否显示选中状态等。
+选中项设置函数
+setCheckedItem(final int position, final boolean checked)：
+所属类：NotesListAdapter
+功能：接收笔记项的位置和是否选中的布尔值两个参数，将对应位置的选中状态记录到mSelectedIndex这个HashMap中，然后调用notifyDataSetChanged方法通知数据集发生了变化，使得视图能根据新的选中状态进行刷新显示，例如更新列表项的选中外观等。
+选择模式相关函数
+isInChoiceMode()：
+所属类：NotesListAdapter
+功能：返回mChoiceMode的值，用于判断当前是否处于选择模式，外部代码可以根据这个返回值来决定是否显示选择相关的操作界面元素（如全选按钮等）。
+setChoiceMode(boolean mode)：
+所属类：NotesListAdapter
+功能：接收一个布尔值参数用于设置选择模式，先清空之前记录的选中项信息（通过mSelectedIndex.clear），然后将传入的布尔值赋值给mChoiceMode，改变整个适配器的选择模式状态，后续的选择操作会依据新的模式进行处理。
+ */
+
+package net.micode.notes.ui;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.util.Log;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.CursorAdapter;
+
+import net.micode.notes.data.Notes;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+
+
+public class NotesListAdapter extends CursorAdapter {
+    private static final String TAG = "NotesListAdapter";
+    private Context mContext;
+    private HashMap<Integer, Boolean> mSelectedIndex;
+    private int mNotesCount;
+    private boolean mChoiceMode;
+
+    public static class AppWidgetAttribute {
+        public int widgetId;
+        public int widgetType;
+    };
+
+    public NotesListAdapter(Context context) {
+        super(context, null);
+        mSelectedIndex = new HashMap<Integer, Boolean>();
+        mContext = context;
+        mNotesCount = 0;
+    }
+
+    @Override
+    public View newView(Context context, Cursor cursor, ViewGroup parent) {
+        return new NotesListItem(context);
+    }
+
+    @Override
+    public void bindView(View view, Context context, Cursor cursor) {
+        if (view instanceof NotesListItem) {
+            NoteItemData itemData = new NoteItemData(context, cursor);
+            ((NotesListItem) view).bind(context, itemData, mChoiceMode,
+                    isSelectedItem(cursor.getPosition()));
+        }
+    }
+
+    public void setCheckedItem(final int position, final boolean checked) {
+        mSelectedIndex.put(position, checked);
+        notifyDataSetChanged();
+    }
+
+    public boolean isInChoiceMode() {
+        return mChoiceMode;
+    }
+
+    public void setChoiceMode(boolean mode) {
+        mSelectedIndex.clear();
+        mChoiceMode = mode;
+    }
+
+    public void selectAll(boolean checked) {
+        Cursor cursor = getCursor();
+        for (int i = 0; i < getCount(); i++) {
+            if (cursor.moveToPosition(i)) {
+                if (NoteItemData.getNoteType(cursor) == Notes.TYPE_NOTE) {
+                    setCheckedItem(i, checked);
+                }
+            }
+        }
+    }
+
+    public HashSet<Long> getSelectedItemIds() {
+        HashSet<Long> itemSet = new HashSet<Long>();
+        for (Integer position : mSelectedIndex.keySet()) {
+            if (mSelectedIndex.get(position) == true) {
+                Long id = getItemId(position);
+                if (id == Notes.ID_ROOT_FOLDER) {
+                    Log.d(TAG, "Wrong item id, should not happen");
+                } else {
+                    itemSet.add(id);
+                }
+            }
+        }
+
+        return itemSet;
+    }
+
+    public HashSet<AppWidgetAttribute> getSelectedWidget() {
+        HashSet<AppWidgetAttribute> itemSet = new HashSet<AppWidgetAttribute>();
+        for (Integer position : mSelectedIndex.keySet()) {
+            if (mSelectedIndex.get(position) == true) {
+                Cursor c = (Cursor) getItem(position);
+                if (c != null) {
+                    AppWidgetAttribute widget = new AppWidgetAttribute();
+                    NoteItemData item = new NoteItemData(mContext, c);
+                    widget.widgetId = item.getWidgetId();
+                    widget.widgetType = item.getWidgetType();
+                    itemSet.add(widget);
+                    /**
+                     * Don't close cursor here, only the adapter could close it
+                     */
+                } else {
+                    Log.e(TAG, "Invalid cursor");
+                    return null;
+                }
+            }
+        }
+        return itemSet;
+    }
+
+    public int getSelectedCount() {
+        Collection<Boolean> values = mSelectedIndex.values();
+        if (null == values) {
+            return 0;
+        }
+        Iterator<Boolean> iter = values.iterator();
+        int count = 0;
+        while (iter.hasNext()) {
+            if (true == iter.next()) {
+                count++;
+            }
+        }
+        return count;
+    }
+
+    public boolean isAllSelected() {
+        int checkedCount = getSelectedCount();
+        return (checkedCount != 0 && checkedCount == mNotesCount);
+    }
+
+    public boolean isSelectedItem(final int position) {
+        if (null == mSelectedIndex.get(position)) {
+            return false;
+        }
+        return mSelectedIndex.get(position);
+    }
+
+    @Override
+    protected void onContentChanged() {
+        super.onContentChanged();
+        calcNotesCount();
+    }
+
+    @Override
+    public void changeCursor(Cursor cursor) {
+        super.changeCursor(cursor);
+        calcNotesCount();
+    }
+
+    private void calcNotesCount() {
+        mNotesCount = 0;
+        for (int i = 0; i < getCount(); i++) {
+            Cursor c = (Cursor) getItem(i);
+            if (c != null) {
+                if (NoteItemData.getNoteType(c) == Notes.TYPE_NOTE) {
+                    mNotesCount++;
+                }
+            } else {
+                Log.e(TAG, "Invalid cursor");
+                return;
+            }
+        }
+    }
+}

java/net/micode/notes/ui/NotesListItem.java

@@ -0,0 +1,154 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了NotesListItem类，它继承自LinearLayout，是用于展示笔记列表中每一项具体内容的自定义视图类。通过绑定NoteItemData类型的数据，根据笔记不同的类型（如通话记录文件夹、普通文件夹、普通笔记等）以及相关属性（是否有提醒、是否是首项、末项等）来设置各个子视图（如TextView、ImageView、CheckBox等）的显示内容和可见性，并设置该项的背景样式，以此实现个性化的笔记列表项展示效果，同时提供了获取所绑定数据的方法方便外部获取对应笔记信息。
+函数分析
+构造函数
+NotesListItem(Context context)：
+所属类：NotesListItem
+功能：
+首先调用父类（LinearLayout）的构造函数传入Context，完成基础的初始化。
+通过inflate方法加载名为R.layout.note_item的布局文件到自身，该布局文件应该定义了笔记列表项的具体外观结构，包含了如提醒图标、标题、时间、联系人姓名、复选框等子视图的布局设置。
+接着使用findViewById方法从加载的布局中找到对应的子视图控件并赋值给相应的成员变量（如mAlert、mTitle等），方便后续在bind方法中对这些子视图进行内容设置等操作。
+数据绑定函数
+bind(Context context, NoteItemData data, boolean choiceMode, boolean checked)：
+所属类：NotesListItem
+功能：
+根据传入的选择模式（choiceMode）以及笔记类型（通过data.getType()判断是否为Notes.TYPE_NOTE）来设置复选框（mCheckBox）的可见性和选中状态。如果处于选择模式且是普通笔记类型，则将复选框设为可见并按照传入的checked参数设置其选中状态，否则将其隐藏。
+将传入的NoteItemData实例赋值给mItemData成员变量，用于后续可能的获取数据操作。
+接着依据笔记的不同情况进行具体的视图内容设置：
+如果笔记的ID是通话记录文件夹的ID（Notes.ID_CALL_RECORD_FOLDER），则隐藏联系人姓名视图（mCallName），显示提醒图标（mAlert），设置标题的文本外观样式（通过setTextAppearance方法），并设置标题文本为通话记录文件夹名称加上包含笔记数量的格式化字符串，同时设置提醒图标的资源为通话记录对应的图标（R.drawable.call_record）。
+如果笔记的父ID是通话记录文件夹的ID，则显示联系人姓名视图并设置其文本为笔记关联的联系人姓名（通过data.getCallName()获取），设置标题文本外观样式并将标题文本设置为格式化后的笔记内容片段（通过DataUtils.getFormattedSnippet方法获取），再根据笔记是否有提醒（通过data.hasAlert()判断）来设置提醒图标的可见性和对应图标资源（有提醒则显示时钟图标）。
+对于其他情况，如果是普通文件夹类型（data.getType() == Notes.TYPE_FOLDER），则隐藏联系人姓名视图，设置标题文本外观样式，并将标题文本设置为笔记内容片段加上包含笔记数量的格式化字符串，同时隐藏提醒图标；如果是普通笔记类型，则设置标题文本外观样式，并将标题文本设置为格式化后的笔记内容片段，再根据是否有提醒来设置提醒图标的可见性和对应图标资源。
+最后通过mTime.setText方法设置时间文本为根据笔记修改日期（通过data.getModifiedDate()获取）格式化后的相对时间字符串（通过DateUtils.getRelativeTimeSpanString方法获取），并调用setBackground方法根据笔记数据来设置该项的背景样式，完成整个笔记列表项的内容和样式设置。
+背景设置函数
+setBackground(NoteItemData data)：
+所属类：NotesListItem
+功能：
+首先获取笔记数据中的背景颜色ID（通过data.getBgColorId()）。
+如果笔记类型是普通笔记类型（data.getType() == Notes.TYPE_NOTE），则进一步根据笔记在列表中的位置关系（是否是单个、首项、末项、跟随文件夹等情况，通过data.isSingle()、data.isFirst()等方法判断）来设置该项的背景资源，分别调用NoteItemBgResources类中对应的获取背景资源方法（如getNoteBgSingleRes、getNoteBgLastRes等）来获取相应的背景资源并设置给自身（通过setBackgroundResource方法），实现不同位置普通笔记的差异化背景显示效果。
+如果笔记类型不是普通笔记类型（即其他类型，比如文件夹类型），则统一调用NoteItemBgResources.getFolderBgRes方法获取文件夹对应的背景资源并设置给自身，确保文件夹有对应的合适背景样式。
+获取数据函数
+getItemData()：
+所属类：NotesListItem
+功能：返回成员变量mItemData，外部代码可以通过调用这个方法获取当前NotesListItem所绑定的NoteItemData实例，进而获取笔记的各项详细信息，方便在其他业务逻辑中使用这些数据，比如获取笔记ID、内容片段等信息。
+ */
+
+package net.micode.notes.ui;
+
+import android.content.Context;
+import android.text.format.DateUtils;
+import android.view.View;
+import android.widget.CheckBox;
+import android.widget.ImageView;
+import android.widget.LinearLayout;
+import android.widget.TextView;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.tool.DataUtils;
+import net.micode.notes.tool.ResourceParser.NoteItemBgResources;
+
+
+public class NotesListItem extends LinearLayout {
+    private ImageView mAlert;
+    private TextView mTitle;
+    private TextView mTime;
+    private TextView mCallName;
+    private NoteItemData mItemData;
+    private CheckBox mCheckBox;
+
+    public NotesListItem(Context context) {
+        super(context);
+        inflate(context, R.layout.note_item, this);
+        mAlert = (ImageView) findViewById(R.id.iv_alert_icon);
+        mTitle = (TextView) findViewById(R.id.tv_title);
+        mTime = (TextView) findViewById(R.id.tv_time);
+        mCallName = (TextView) findViewById(R.id.tv_name);
+        mCheckBox = (CheckBox) findViewById(android.R.id.checkbox);
+    }
+
+    public void bind(Context context, NoteItemData data, boolean choiceMode, boolean checked) {
+        if (choiceMode && data.getType() == Notes.TYPE_NOTE) {
+            mCheckBox.setVisibility(View.VISIBLE);
+            mCheckBox.setChecked(checked);
+        } else {
+            mCheckBox.setVisibility(View.GONE);
+        }
+
+        mItemData = data;
+        if (data.getId() == Notes.ID_CALL_RECORD_FOLDER) {
+            mCallName.setVisibility(View.GONE);
+            mAlert.setVisibility(View.VISIBLE);
+            mTitle.setTextAppearance(context, R.style.TextAppearancePrimaryItem);
+            mTitle.setText(context.getString(R.string.call_record_folder_name)
+                    + context.getString(R.string.format_folder_files_count, data.getNotesCount()));
+            mAlert.setImageResource(R.drawable.call_record);
+        } else if (data.getParentId() == Notes.ID_CALL_RECORD_FOLDER) {
+            mCallName.setVisibility(View.VISIBLE);
+            mCallName.setText(data.getCallName());
+            mTitle.setTextAppearance(context,R.style.TextAppearanceSecondaryItem);
+            mTitle.setText(DataUtils.getFormattedSnippet(data.getSnippet()));
+            if (data.hasAlert()) {
+                mAlert.setImageResource(R.drawable.clock);
+                mAlert.setVisibility(View.VISIBLE);
+            } else {
+                mAlert.setVisibility(View.GONE);
+            }
+        } else {
+            mCallName.setVisibility(View.GONE);
+            mTitle.setTextAppearance(context, R.style.TextAppearancePrimaryItem);
+
+            if (data.getType() == Notes.TYPE_FOLDER) {
+                mTitle.setText(data.getSnippet()
+                        + context.getString(R.string.format_folder_files_count,
+                                data.getNotesCount()));
+                mAlert.setVisibility(View.GONE);
+            } else {
+                mTitle.setText(DataUtils.getFormattedSnippet(data.getSnippet()));
+                if (data.hasAlert()) {
+                    mAlert.setImageResource(R.drawable.clock);
+                    mAlert.setVisibility(View.VISIBLE);
+                } else {
+                    mAlert.setVisibility(View.GONE);
+                }
+            }
+        }
+        mTime.setText(DateUtils.getRelativeTimeSpanString(data.getModifiedDate()));
+
+        setBackground(data);
+    }
+
+    private void setBackground(NoteItemData data) {
+        int id = data.getBgColorId();
+        if (data.getType() == Notes.TYPE_NOTE) {
+            if (data.isSingle() || data.isOneFollowingFolder()) {
+                setBackgroundResource(NoteItemBgResources.getNoteBgSingleRes(id));
+            } else if (data.isLast()) {
+                setBackgroundResource(NoteItemBgResources.getNoteBgLastRes(id));
+            } else if (data.isFirst() || data.isMultiFollowingFolder()) {
+                setBackgroundResource(NoteItemBgResources.getNoteBgFirstRes(id));
+            } else {
+                setBackgroundResource(NoteItemBgResources.getNoteBgNormalRes(id));
+            }
+        } else {
+            setBackgroundResource(NoteItemBgResources.getFolderBgRes());
+        }
+    }
+
+    public NoteItemData getItemData() {
+        return mItemData;
+    }
+}

java/net/micode/notes/ui/NotesPreferenceActivity.java

@@ -0,0 +1,409 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 总体分析
+这段 Java 代码定义了NotesPreferenceActivity类，它继承自PreferenceActivity，主要用于实现安卓应用中与笔记相关的设置界面及相关功能逻辑。在这个类中，涉及到账户管理（如选择、设置、移除同步账户）、同步操作（启动、取消同步以及展示同步状态等）、界面 UI 的动态刷新、接收广播更新界面显示等功能，同时还处理了返回键点击等操作，整体为用户提供了一个可配置笔记同步相关设置以及查看同步状态的交互界面。
+函数分析
+onCreate方法
+所属类：NotesPreferenceActivity
+功能：
+首先调用父类的onCreate方法完成基础的初始化工作。
+通过getActionBar().setDisplayHomeAsUpEnabled(true)设置 ActionBar 上的返回按钮可用，方便用户返回上一级界面。
+使用addPreferencesFromResource方法加载名为R.xml.preferences的偏好设置资源文件，用于构建设置界面的初始布局和选项内容。
+获取名为PREFERENCE_SYNC_ACCOUNT_KEY的PreferenceCategory对象（用于后续添加、管理与同步账户相关的偏好设置选项），创建一个GTaskReceiver广播接收者实例（用于接收同步服务相关广播），并注册该广播接收者，监听GTaskSyncService.GTASK_SERVICE_BROADCAST_NAME对应的广播消息。
+将存储原始账户信息的mOriAccounts初始化为null，通过LayoutInflater加载名为R.layout.settings_header的布局文件并添加到列表视图头部，用于展示一些自定义的界面头部内容。
+onResume方法
+所属类：NotesPreferenceActivity
+功能：
+首先调用父类的onResume方法保证原生相关逻辑执行，比如恢复界面状态等操作。
+判断mHasAddedAccount标志位，如果用户添加了新账户（该标志位为true），获取当前的谷歌账户列表，对比原始账户列表（mOriAccounts）长度，若新列表更长，则遍历新账户列表，查找新增的账户，找到后调用setSyncAccount方法设置新的同步账户，并跳出循环，实现自动设置同步账户的逻辑。
+调用refreshUI方法刷新整个设置界面的显示内容，确保界面展示的信息（如账户选项、同步按钮状态等）是最新的。
+onDestroy方法
+所属类：NotesPreferenceActivity
+功能：
+判断mReceiver是否为null，如果不为null，则调用unregisterReceiver方法注销之前注册的GTaskReceiver广播接收者，避免出现内存泄漏等问题，然后调用父类的onDestroy方法执行原生的销毁相关逻辑。
+ */
+
+package net.micode.notes.ui;
+
+import android.accounts.Account;
+import android.accounts.AccountManager;
+import android.app.ActionBar;
+import android.app.AlertDialog;
+import android.content.BroadcastReceiver;
+import android.content.ContentValues;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.content.SharedPreferences;
+import android.os.Bundle;
+import android.preference.Preference;
+import android.preference.Preference.OnPreferenceClickListener;
+import android.preference.PreferenceActivity;
+import android.preference.PreferenceCategory;
+import android.text.TextUtils;
+import android.text.format.DateFormat;
+import android.view.LayoutInflater;
+import android.view.Menu;
+import android.view.MenuItem;
+import android.view.View;
+import android.widget.Button;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.gtask.remote.GTaskSyncService;
+
+
+public class NotesPreferenceActivity extends PreferenceActivity {
+    public static final String PREFERENCE_NAME = "notes_preferences";
+
+    public static final String PREFERENCE_SYNC_ACCOUNT_NAME = "pref_key_account_name";
+
+    public static final String PREFERENCE_LAST_SYNC_TIME = "pref_last_sync_time";
+
+    public static final String PREFERENCE_SET_BG_COLOR_KEY = "pref_key_bg_random_appear";
+
+    private static final String PREFERENCE_SYNC_ACCOUNT_KEY = "pref_sync_account_key";
+
+    private static final String AUTHORITIES_FILTER_KEY = "authorities";
+
+    private PreferenceCategory mAccountCategory;
+
+    private GTaskReceiver mReceiver;
+
+    private Account[] mOriAccounts;
+
+    private boolean mHasAddedAccount;
+
+    @Override
+    protected void onCreate(Bundle icicle) {
+        super.onCreate(icicle);
+
+        /* using the app icon for navigation */
+        getActionBar().setDisplayHomeAsUpEnabled(true);
+
+        addPreferencesFromResource(R.xml.preferences);
+        mAccountCategory = (PreferenceCategory) findPreference(PREFERENCE_SYNC_ACCOUNT_KEY);
+        mReceiver = new GTaskReceiver();
+        IntentFilter filter = new IntentFilter();
+        filter.addAction(GTaskSyncService.GTASK_SERVICE_BROADCAST_NAME);
+        registerReceiver(mReceiver, filter);
+
+        mOriAccounts = null;
+        View header = LayoutInflater.from(this).inflate(R.layout.settings_header, null);
+        getListView().addHeaderView(header, null, true);
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+
+        // need to set sync account automatically if user has added a new
+        // account
+        if (mHasAddedAccount) {
+            Account[] accounts = getGoogleAccounts();
+            if (mOriAccounts != null && accounts.length > mOriAccounts.length) {
+                for (Account accountNew : accounts) {
+                    boolean found = false;
+                    for (Account accountOld : mOriAccounts) {
+                        if (TextUtils.equals(accountOld.name, accountNew.name)) {
+                            found = true;
+                            break;
+                        }
+                    }
+                    if (!found) {
+                        setSyncAccount(accountNew.name);
+                        break;
+                    }
+                }
+            }
+        }
+
+        refreshUI();
+    }
+
+    @Override
+    protected void onDestroy() {
+        if (mReceiver != null) {
+            unregisterReceiver(mReceiver);
+        }
+        super.onDestroy();
+    }
+
+    private void loadAccountPreference() {
+        mAccountCategory.removeAll();
+
+        Preference accountPref = new Preference(this);
+        final String defaultAccount = getSyncAccountName(this);
+        accountPref.setTitle(getString(R.string.preferences_account_title));
+        accountPref.setSummary(getString(R.string.preferences_account_summary));
+        accountPref.setOnPreferenceClickListener(new OnPreferenceClickListener() {
+            public boolean onPreferenceClick(Preference preference) {
+                if (!GTaskSyncService.isSyncing()) {
+                    if (TextUtils.isEmpty(defaultAccount)) {
+                        // the first time to set account
+                        showSelectAccountAlertDialog();
+                    } else {
+                        // if the account has already been set, we need to promp
+                        // user about the risk
+                        showChangeAccountConfirmAlertDialog();
+                    }
+                } else {
+                    Toast.makeText(NotesPreferenceActivity.this,
+                            R.string.preferences_toast_cannot_change_account, Toast.LENGTH_SHORT)
+                            .show();
+                }
+                return true;
+            }
+        });
+
+        mAccountCategory.addPreference(accountPref);
+    }
+
+    private void loadSyncButton() {
+        Button syncButton = (Button) findViewById(R.id.preference_sync_button);
+        TextView lastSyncTimeView = (TextView) findViewById(R.id.prefenerece_sync_status_textview);
+
+        // set button state
+        if (GTaskSyncService.isSyncing()) {
+            syncButton.setText(getString(R.string.preferences_button_sync_cancel));
+            syncButton.setOnClickListener(new View.OnClickListener() {
+                public void onClick(View v) {
+                    GTaskSyncService.cancelSync(NotesPreferenceActivity.this);
+                }
+            });
+        } else {
+            syncButton.setText(getString(R.string.preferences_button_sync_immediately));
+            syncButton.setOnClickListener(new View.OnClickListener() {
+                public void onClick(View v) {
+                    GTaskSyncService.startSync(NotesPreferenceActivity.this);
+                }
+            });
+        }
+        syncButton.setEnabled(!TextUtils.isEmpty(getSyncAccountName(this)));
+
+        // set last sync time
+        if (GTaskSyncService.isSyncing()) {
+            lastSyncTimeView.setText(GTaskSyncService.getProgressString());
+            lastSyncTimeView.setVisibility(View.VISIBLE);
+        } else {
+            long lastSyncTime = getLastSyncTime(this);
+            if (lastSyncTime != 0) {
+                lastSyncTimeView.setText(getString(R.string.preferences_last_sync_time,
+                        DateFormat.format(getString(R.string.preferences_last_sync_time_format),
+                                lastSyncTime)));
+                lastSyncTimeView.setVisibility(View.VISIBLE);
+            } else {
+                lastSyncTimeView.setVisibility(View.GONE);
+            }
+        }
+    }
+
+    private void refreshUI() {
+        loadAccountPreference();
+        loadSyncButton();
+    }
+
+    private void showSelectAccountAlertDialog() {
+        AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
+
+        View titleView = LayoutInflater.from(this).inflate(R.layout.account_dialog_title, null);
+        TextView titleTextView = (TextView) titleView.findViewById(R.id.account_dialog_title);
+        titleTextView.setText(getString(R.string.preferences_dialog_select_account_title));
+        TextView subtitleTextView = (TextView) titleView.findViewById(R.id.account_dialog_subtitle);
+        subtitleTextView.setText(getString(R.string.preferences_dialog_select_account_tips));
+
+        dialogBuilder.setCustomTitle(titleView);
+        dialogBuilder.setPositiveButton(null, null);
+
+        Account[] accounts = getGoogleAccounts();
+        String defAccount = getSyncAccountName(this);
+
+        mOriAccounts = accounts;
+        mHasAddedAccount = false;
+
+        if (accounts.length > 0) {
+            CharSequence[] items = new CharSequence[accounts.length];
+            final CharSequence[] itemMapping = items;
+            int checkedItem = -1;
+            int index = 0;
+            for (Account account : accounts) {
+                if (TextUtils.equals(account.name, defAccount)) {
+                    checkedItem = index;
+                }
+                items[index++] = account.name;
+            }
+            dialogBuilder.setSingleChoiceItems(items, checkedItem,
+                    new DialogInterface.OnClickListener() {
+                        public void onClick(DialogInterface dialog, int which) {
+                            setSyncAccount(itemMapping[which].toString());
+                            dialog.dismiss();
+                            refreshUI();
+                        }
+                    });
+        }
+
+        View addAccountView = LayoutInflater.from(this).inflate(R.layout.add_account_text, null);
+        dialogBuilder.setView(addAccountView);
+
+        final AlertDialog dialog = dialogBuilder.show();
+        addAccountView.setOnClickListener(new View.OnClickListener() {
+            public void onClick(View v) {
+                mHasAddedAccount = true;
+                Intent intent = new Intent("android.settings.ADD_ACCOUNT_SETTINGS");
+                intent.putExtra(AUTHORITIES_FILTER_KEY, new String[] {
+                    "gmail-ls"
+                });
+                startActivityForResult(intent, -1);
+                dialog.dismiss();
+            }
+        });
+    }
+
+    private void showChangeAccountConfirmAlertDialog() {
+        AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
+
+        View titleView = LayoutInflater.from(this).inflate(R.layout.account_dialog_title, null);
+        TextView titleTextView = (TextView) titleView.findViewById(R.id.account_dialog_title);
+        titleTextView.setText(getString(R.string.preferences_dialog_change_account_title,
+                getSyncAccountName(this)));
+        TextView subtitleTextView = (TextView) titleView.findViewById(R.id.account_dialog_subtitle);
+        subtitleTextView.setText(getString(R.string.preferences_dialog_change_account_warn_msg));
+        dialogBuilder.setCustomTitle(titleView);
+
+        CharSequence[] menuItemArray = new CharSequence[] {
+                getString(R.string.preferences_menu_change_account),
+                getString(R.string.preferences_menu_remove_account),
+                getString(R.string.preferences_menu_cancel)
+        };
+        dialogBuilder.setItems(menuItemArray, new DialogInterface.OnClickListener() {
+            public void onClick(DialogInterface dialog, int which) {
+                if (which == 0) {
+                    showSelectAccountAlertDialog();
+                } else if (which == 1) {
+                    removeSyncAccount();
+                    refreshUI();
+                }
+            }
+        });
+        dialogBuilder.show();
+    }
+
+    private Account[] getGoogleAccounts() {
+        AccountManager accountManager = AccountManager.get(this);
+        return accountManager.getAccountsByType("com.google");
+    }
+
+    private void setSyncAccount(String account) {
+        if (!getSyncAccountName(this).equals(account)) {
+            SharedPreferences settings = getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
+            SharedPreferences.Editor editor = settings.edit();
+            if (account != null) {
+                editor.putString(PREFERENCE_SYNC_ACCOUNT_NAME, account);
+            } else {
+                editor.putString(PREFERENCE_SYNC_ACCOUNT_NAME, "");
+            }
+            editor.commit();
+
+            // clean up last sync time
+            setLastSyncTime(this, 0);
+
+            // clean up local gtask related info
+            new Thread(new Runnable() {
+                public void run() {
+                    ContentValues values = new ContentValues();
+                    values.put(NoteColumns.GTASK_ID, "");
+                    values.put(NoteColumns.SYNC_ID, 0);
+                    getContentResolver().update(Notes.CONTENT_NOTE_URI, values, null, null);
+                }
+            }).start();
+
+            Toast.makeText(NotesPreferenceActivity.this,
+                    getString(R.string.preferences_toast_success_set_accout, account),
+                    Toast.LENGTH_SHORT).show();
+        }
+    }
+
+    private void removeSyncAccount() {
+        SharedPreferences settings = getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
+        SharedPreferences.Editor editor = settings.edit();
+        if (settings.contains(PREFERENCE_SYNC_ACCOUNT_NAME)) {
+            editor.remove(PREFERENCE_SYNC_ACCOUNT_NAME);
+        }
+        if (settings.contains(PREFERENCE_LAST_SYNC_TIME)) {
+            editor.remove(PREFERENCE_LAST_SYNC_TIME);
+        }
+        editor.commit();
+
+        // clean up local gtask related info
+        new Thread(new Runnable() {
+            public void run() {
+                ContentValues values = new ContentValues();
+                values.put(NoteColumns.GTASK_ID, "");
+                values.put(NoteColumns.SYNC_ID, 0);
+                getContentResolver().update(Notes.CONTENT_NOTE_URI, values, null, null);
+            }
+        }).start();
+    }
+
+    public static String getSyncAccountName(Context context) {
+        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME,
+                Context.MODE_PRIVATE);
+        return settings.getString(PREFERENCE_SYNC_ACCOUNT_NAME, "");
+    }
+
+    public static void setLastSyncTime(Context context, long time) {
+        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME,
+                Context.MODE_PRIVATE);
+        SharedPreferences.Editor editor = settings.edit();
+        editor.putLong(PREFERENCE_LAST_SYNC_TIME, time);
+        editor.commit();
+    }
+
+    public static long getLastSyncTime(Context context) {
+        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME,
+                Context.MODE_PRIVATE);
+        return settings.getLong(PREFERENCE_LAST_SYNC_TIME, 0);
+    }
+
+    private class GTaskReceiver extends BroadcastReceiver {
+
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            refreshUI();
+            if (intent.getBooleanExtra(GTaskSyncService.GTASK_SERVICE_BROADCAST_IS_SYNCING, false)) {
+                TextView syncStatus = (TextView) findViewById(R.id.prefenerece_sync_status_textview);
+                syncStatus.setText(intent
+                        .getStringExtra(GTaskSyncService.GTASK_SERVICE_BROADCAST_PROGRESS_MSG));
+            }
+
+        }
+    }
+
+    public boolean onOptionsItemSelected(MenuItem item) {
+        switch (item.getItemId()) {
+            case android.R.id.home:
+                Intent intent = new Intent(this, NotesListActivity.class);
+                intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
+                startActivity(intent);
+                return true;
+            default:
+                return false;
+        }
+    }
+}

java/net/micode/notes/widget/NoteWidgetProvider.java

@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.widget;
+import android.app.PendingIntent;
+import android.appwidget.AppWidgetManager;
+import android.appwidget.AppWidgetProvider;
+import android.content.ContentValues;
+import android.content.Context;
+import android.content.Intent;
+import android.database.Cursor;
+import android.util.Log;
+import android.widget.RemoteViews;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.tool.ResourceParser;
+import net.micode.notes.ui.NoteEditActivity;
+import net.micode.notes.ui.NotesListActivity;
+
+public abstract class NoteWidgetProvider extends AppWidgetProvider {
+    public static final String [] PROJECTION = new String [] {
+        NoteColumns.ID,
+        NoteColumns.BG_COLOR_ID,
+        NoteColumns.SNIPPET
+    };
+
+    public static final int COLUMN_ID           = 0;
+    public static final int COLUMN_BG_COLOR_ID  = 1;
+    public static final int COLUMN_SNIPPET      = 2;
+
+    private static final String TAG = "NoteWidgetProvider";
+
+    @Override
+    public void onDeleted(Context context, int[] appWidgetIds) {
+        ContentValues values = new ContentValues();
+        values.put(NoteColumns.WIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
+        for (int i = 0; i < appWidgetIds.length; i++) {
+            context.getContentResolver().update(Notes.CONTENT_NOTE_URI,
+                    values,
+                    NoteColumns.WIDGET_ID + "=?",
+                    new String[] { String.valueOf(appWidgetIds[i])});
+        }
+    }
+
+    private Cursor getNoteWidgetInfo(Context context, int widgetId) {
+        return context.getContentResolver().query(Notes.CONTENT_NOTE_URI,
+                PROJECTION,
+                NoteColumns.WIDGET_ID + "=? AND " + NoteColumns.PARENT_ID + "<>?",
+                new String[] { String.valueOf(widgetId), String.valueOf(Notes.ID_TRASH_FOLER) },
+                null);
+    }
+
+    protected void update(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
+        update(context, appWidgetManager, appWidgetIds, false);
+    }
+
+    private void update(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds,
+            boolean privacyMode) {
+        for (int i = 0; i < appWidgetIds.length; i++) {
+            if (appWidgetIds[i] != AppWidgetManager.INVALID_APPWIDGET_ID) {
+                int bgId = ResourceParser.getDefaultBgId(context);
+                String snippet = "";
+                Intent intent = new Intent(context, NoteEditActivity.class);
+                intent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
+                intent.putExtra(Notes.INTENT_EXTRA_WIDGET_ID, appWidgetIds[i]);
+                intent.putExtra(Notes.INTENT_EXTRA_WIDGET_TYPE, getWidgetType());
+
+                Cursor c = getNoteWidgetInfo(context, appWidgetIds[i]);
+                if (c != null && c.moveToFirst()) {
+                    if (c.getCount() > 1) {
+                        Log.e(TAG, "Multiple message with same widget id:" + appWidgetIds[i]);
+                        c.close();
+                        return;
+                    }
+                    snippet = c.getString(COLUMN_SNIPPET);
+                    bgId = c.getInt(COLUMN_BG_COLOR_ID);
+                    intent.putExtra(Intent.EXTRA_UID, c.getLong(COLUMN_ID));
+                    intent.setAction(Intent.ACTION_VIEW);
+                } else {
+                    snippet = context.getResources().getString(R.string.widget_havenot_content);
+                    intent.setAction(Intent.ACTION_INSERT_OR_EDIT);
+                }
+
+                if (c != null) {
+                    c.close();
+                }
+
+                RemoteViews rv = new RemoteViews(context.getPackageName(), getLayoutId());
+                rv.setImageViewResource(R.id.widget_bg_image, getBgResourceId(bgId));
+                intent.putExtra(Notes.INTENT_EXTRA_BACKGROUND_ID, bgId);
+                /**
+                 * Generate the pending intent to start host for the widget
+                 */
+                PendingIntent pendingIntent = null;
+                if (privacyMode) {
+                    rv.setTextViewText(R.id.widget_text,
+                            context.getString(R.string.widget_under_visit_mode));
+                    pendingIntent = PendingIntent.getActivity(context, appWidgetIds[i], new Intent(
+                            context, NotesListActivity.class), PendingIntent.FLAG_UPDATE_CURRENT);
+                } else {
+                    rv.setTextViewText(R.id.widget_text, snippet);
+                    pendingIntent = PendingIntent.getActivity(context, appWidgetIds[i], intent,
+                            PendingIntent.FLAG_UPDATE_CURRENT);
+                }
+
+                rv.setOnClickPendingIntent(R.id.widget_text, pendingIntent);
+                appWidgetManager.updateAppWidget(appWidgetIds[i], rv);
+            }
+        }
+    }
+
+    protected abstract int getBgResourceId(int bgId);
+
+    protected abstract int getLayoutId();
+
+    protected abstract int getWidgetType();
+}

java/net/micode/notes/widget/NoteWidgetProvider_2x.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.widget;
+
+import android.appwidget.AppWidgetManager;
+import android.content.Context;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.tool.ResourceParser;
+
+
+public class NoteWidgetProvider_2x extends NoteWidgetProvider {
+    @Override
+    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
+        super.update(context, appWidgetManager, appWidgetIds);
+    }
+
+    @Override
+    protected int getLayoutId() {
+        return R.layout.widget_2x;
+    }
+
+    @Override
+    protected int getBgResourceId(int bgId) {
+        return ResourceParser.WidgetBgResources.getWidget2xBgResource(bgId);
+    }
+
+    @Override
+    protected int getWidgetType() {
+        return Notes.TYPE_WIDGET_2X;
+    }
+}

java/net/micode/notes/widget/NoteWidgetProvider_4x.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.widget;
+
+import android.appwidget.AppWidgetManager;
+import android.content.Context;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+import net.micode.notes.tool.ResourceParser;
+
+
+public class NoteWidgetProvider_4x extends NoteWidgetProvider {
+    @Override
+    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
+        super.update(context, appWidgetManager, appWidgetIds);
+    }
+
+    protected int getLayoutId() {
+        return R.layout.widget_4x;
+    }
+
+    @Override
+    protected int getBgResourceId(int bgId) {
+        return ResourceParser.WidgetBgResources.getWidget4xBgResource(bgId);
+    }
+
+    @Override
+    protected int getWidgetType() {
+        return Notes.TYPE_WIDGET_4X;
+    }
+}

res/color/primary_text_dark.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!-- Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+     在安卓开发中，selector通常用于根据不同的控件状态来设置不同的外观属性，比如这里是通过state_pressed（按下状态）、state_selected（选中状态）来分别指定对应的颜色，而对于其他未明确指定的常规状态则设置了一个默认颜色，以此实现交互过程中界面元素视觉效果的动态变化，常应用于按钮等可交互控件上，使其能根据用户操作展示不同的颜色反馈，增强用户体验。
+-->
+
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+  <item android:state_pressed="true" android:color="#88555555" />
+  <item android:state_selected="true" android:color="#ff999999" />
+  <item android:color="#ff000000" />
+</selector>

res/color/secondary_text_dark.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!-- Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+  <item android:color="#50000000" />
+</selector>