提交精读data、ui1000

doc/data/data/Contact.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.
+ */
+
+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 {//联系人
+    private static HashMap<String, String> sContactCache;
+    private static final String TAG = "Contact";
+    // 定义字符串CALLER_ID_SELECTION
+    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 = '+')";
+//获取联系人
+    public static String getContact(Context context, String phoneNumber) {
+        if(sContactCache == null) {
+            sContactCache = new HashMap<String, String>();
+        }
+// 查找HashMap中是否已有phoneNumber信息
+        if(sContactCache.containsKey(phoneNumber)) {
+            return sContactCache.get(phoneNumber);
+        }
+
+        String selection = CALLER_ID_SELECTION.replace("+",
+                PhoneNumberUtils.toCallerIDMinMatch(phoneNumber));
+        // 查找数据库中phoneNumber的信息
+        Cursor cursor = context.getContentResolver().query(
+                Data.CONTENT_URI,
+                new String [] { Phone.DISPLAY_NAME },
+                selection,
+                new String[] { phoneNumber },
+                null);
+// 判定查询结果
+        // moveToFirst()返回第一条
+        if (cursor != null && cursor.moveToFirst()) {
+            try {
+                // 找到相关信息
+                String name = cursor.getString(0);
+                sContactCache.put(phoneNumber, name);
+                return name;
+                // 异常
+            } catch (IndexOutOfBoundsException e) {
+                Log.e(TAG, " Cursor get string error " + e.toString());
+                return null;
+            } finally {
+                cursor.close();
+            }
+            // 未找到相关信息
+        } else {
+            Log.d(TAG, "No contact matched with number:" + phoneNumber);
+            return null;
+        }
+    }
+}

doc/data/data/Notes.java

@@ -0,0 +1,283 @@
+/*
+ * 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.data;
+
+import android.net.Uri;
+public class Notes {
+    // Notes 类中定义了很多常量，这些常量大多是int型和string型
+
+    public static final String AUTHORITY = "micode_notes";
+    public static final String TAG = "Notes";
+    //以下三个常量对NoteColumns.TYPE的值进行设置时会用到
+    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");
+//定义查询便签和文件夹的指针。
+    /**
+     * Uri to query data
+     */
+    public static final Uri CONTENT_DATA_URI = Uri.parse("content://" + AUTHORITY + "/data");
+    //定义查找数据的指针。
+    // 定义NoteColumns的常量,用于后面创建数据库的表头
+    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";//为什么会有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";//同步
+
+        /**
+         * 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";
+    }//这些常量主要是定义便签的属性的。
+    // 定义DataColumns的常量,用于后面创建数据库的表头
+    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";
+    }//主要是定义存储便签内容数据的
+
+    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");
+    }//文本内容的数据结构
+
+    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");
+    }//电话内容的数据结构
+}

doc/data/data/NotesDatabaseHelper.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.
+ */
+
+package net.micode.notes.data;
+
+import android.content.ContentValues;//就是用于保存一些数据（string boolean byte double float int long short ...）信息，这些信息可以被数据库操作时使用。
+import android.content.Context;//加载和访问资源。（android中主要是这两个功能，但是这里具体不清楚）
+import android.database.sqlite.SQLiteDatabase;//主要提供了对应于添加、删除、更新、查询的操作方法： insert()、delete()、update()和query()。配合content.values
+import android.database.sqlite.SQLiteOpenHelper;//用来管理数据的创建和版本更新
+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;
+//数据库操作，用SQLOpenhelper,对一些note和文件进行数据库的操作，比如删除文件后，将文件里的note也相应删除
+
+public class NotesDatabaseHelper extends SQLiteOpenHelper {
+    private static final String DB_NAME = "note.db";
+
+    private static final int DB_VERSION = 4;
+
+    public interface TABLE {//接口，分成note和data，在后面的程序里分别使用过
+
+        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" +
+        ")";//数据库中需要存储的项目的名称，就相当于创建一个表格的表头的内容。
+
+    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 ''" +
+        ")";//和上面的功能一样，主要是存储的项目不同
+
+    private static final String CREATE_DATA_NOTE_ID_INDEX_SQL =
+        "CREATE INDEX IF NOT EXISTS note_id_index ON " +
+        TABLE.DATA + "(" + DataColumns.NOTE_ID + ");";//存储便签编号的一个数据表格
+
+    /**
+     * 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";//在文件夹中移入一个Note之后需要更改的数据的表格。
+
+    /**
+     * 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";//在文件夹中移出一个Note之后需要更改的数据的表格。
+
+    /**
+     * 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";//在文件夹中插入一个Note之后需要更改的数据的表格。
+
+    /**
+     * 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";//在文件夹中删除一个Note之后需要更改的数据的表格。
+
+    /**
+     * 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";//在文件夹中对一个Note导入新的数据之后需要更改的数据的表格。
+
+    /**
+     * 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";//Note数据被修改后需要更改的数据的表格。
+
+    /**
+     * 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";//Note数据被删除后需要更改的数据的表格。
+
+    /**
+     * 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";//删除已删除的便签的数据后需要更改的数据的表格。
+
+    /**
+     * 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";//删除已删除的文件夹的便签后需要更改的数据的表格。
+
+    /**
+     * 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";//还原垃圾桶中便签后需要更改的数据的表格。
+
+    public NotesDatabaseHelper(Context context) {
+        super(context, DB_NAME, null, DB_VERSION);
+    }
+    //构造函数，传入数据库的名称和版本
+    public void createNoteTable(SQLiteDatabase db) {
+        db.execSQL(CREATE_NOTE_TABLE_SQL);
+        reCreateNoteTableTriggers(db);
+        createSystemFolder(db);
+        Log.d(TAG, "note table has been created");
+    }//创建表格（用来存储标签属性）
+
+    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);
+    }//execSQL是数据库操作的API，主要是更改行为的SQL语句。
+    //在这里主要是用来重新创建上述定义的表格用的，先删除原来有的数据库的触发器再重新创建新的数据库
+
+
+    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);
+    }//创建几个系统文件夹
+
+    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");
+    }//创建表格（用来存储标签内容）
+
+    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);
+    }//同上面的execSQL
+
+    static synchronized NotesDatabaseHelper getInstance(Context context) {
+        if (mInstance == null) {
+            mInstance = new NotesDatabaseHelper(context);
+        }
+        return mInstance;
+    }//上网查是为解决同一时刻只能有一个线程执行.
+    //在写程序库代码时，有时有一个类需要被所有的其它类使用，
+    //但又要求这个类只能被实例化一次，是个服务类，定义一次，其它类使用同一个这个类的实例
+
+    @Override
+    public void onCreate(SQLiteDatabase db) {
+        createNoteTable(db);
+        createDataTable(db);
+    }//实现两个表格（上面创建的两个表格）
+
+    @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");
+        }
+    }//数据库版本的更新（数据库内容的更改）
+
+    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);
+    }//更新到V2版本
+
+    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);
+    }//更新到V3版本
+
+
+    private void upgradeToV4(SQLiteDatabase db) {
+        db.execSQL("ALTER TABLE " + TABLE.NOTE + " ADD COLUMN " + NoteColumns.VERSION
+                + " INTEGER NOT NULL DEFAULT 0");
+    }
+}//更新到V4版本

doc/data/data/NotesProvider.java

@@ -0,0 +1,332 @@
+/*
+ * 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.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;
+//为存储和获取数据提供接口。可以在不同的应用程序之间共享数据
+//ContentProvider提供的方法
+//query：查询
+//insert：插入
+//update：更新
+//delete：删除
+//getType：得到数据类型
+
+public class NotesProvider extends ContentProvider {
+    // UriMatcher用于匹配Uri
+    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 {// 创建UriMatcher时，调用UriMatcher(UriMatcher.NO_MATCH)表示不匹配任何路径的返回码
+        mMatcher = new UriMatcher(UriMatcher.NO_MATCH);// 把需要匹配Uri路径全部给注册上
+        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.
+     */
+    // 声明 NOTES_SEARCH_PROJECTION
+    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;
+    // 声明NOTES_SNIPPET_SEARCH_QUERY
+    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
+    // Context只有在onCreate()中才被初始化
+    // 对mHelper进行实例化
+    public boolean onCreate() {
+        mHelper = NotesDatabaseHelper.getInstance(getContext());
+        return true;
+    }
+
+    @Override
+    // 查询uri在数据库中对应的位置
+    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
+            String sortOrder) {
+        Cursor c = null;
+        // 获取可读数据库
+        SQLiteDatabase db = mHelper.getReadableDatabase();
+        String id = null;
+        // 匹配查找uri
+        switch (mMatcher.match(uri)) {
+            // 对于不同的匹配值，在数据库中查找相应的条目
+            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) {
+                    // 不合法的参数异常
+                    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) {
+                        // getPathSegments()方法得到一个String的List，
+                        // 在uri.getPathSegments().get(1)为第2个元素
+                        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:
+                // 抛出异常
+                throw new IllegalArgumentException("Unknown URI " + uri);
+        }
+        if (c != null) {
+            c.setNotificationUri(getContext().getContentResolver(), uri);
+        }
+        return c;
+    }
+
+    @Override
+    // 插入一个uri
+    public Uri insert(Uri uri, ContentValues values) {
+        // 获得可写的数据库
+        SQLiteDatabase db = mHelper.getWritableDatabase();
+        long dataId = 0, noteId = 0, insertedId = 0;
+        switch (mMatcher.match(uri)) {
+            // 新增一个条目
+            case URI_NOTE:
+                insertedId = noteId = db.insert(TABLE.NOTE, null, values);
+                break;
+            // 如果存在，查找NOTE_ID
+            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
+        // notifyChange获得一个ContextResolver对象并且更新里面的内容
+        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);
+        }
+        // 返回插入的uri的路径
+        return ContentUris.withAppendedId(uri, insertedId);
+    }
+
+    @Override
+    // 删除一个uri
+    public int delete(Uri uri, String selection, String[] selectionArgs) {
+        //Uri代表要操作的数据，Android上可用的每种资源 -包括 图像、视频片段、音频资源等都可以用Uri来表示。
+        int count = 0;
+        String id = null;
+        // 获得可写的数据库
+        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
+    // 更新一个uri
+    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;
+    }
+    // 将字符串解析成规定格式
+    private String parseSelection(String selection) {
+        return (!TextUtils.isEmpty(selection) ? " AND (" + selection + ')' : "");
+    }
+    //增加一个noteVersion
+    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);
+        }
+// execSQL()方法可以执行insert、delete、update和CREATE TABLE之类有更改行为的SQL语句
+        mHelper.getWritableDatabase().execSQL(sql.toString());
+    }
+
+    @Override
+    public String getType(Uri uri) {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+}

doc/data/ui-1000/AlarmAlertActivity.java

@@ -0,0 +1,192 @@
+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;      //文本在数据库存储中的ID号
+    private String mSnippet;   //闹钟提示时出现的文本片段
+    private static final int SNIPPET_PREW_MAX_LEN = 60;
+    MediaPlayer mPlayer;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        //Bundle类型的数据与Map类型的数据相似，都是以key-value的形式存储数据的
+        //onsaveInstanceState方法是用来保存Activity的状态的
+        //能从onCreate的参数savedInsanceState中获得状态数据
+        requestWindowFeature(Window.FEATURE_NO_TITLE);
+        //界面显示——无标题
+
+        final Window win = getWindow();
+        win.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
+
+        if (!isScreenOn()) {
+            win.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
+                    //保持窗体点亮
+                    | WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
+                    //将窗体点亮
+                    | WindowManager.LayoutParams.FLAG_ALLOW_LOCK_WHILE_SCREEN_ON
+                    //允许窗体点亮时锁屏
+                    | WindowManager.LayoutParams.FLAG_LAYOUT_INSET_DECOR);
+        }//在手机锁屏后如果到了闹钟提示时间，点亮屏幕
+
+        Intent intent = getIntent();
+
+        try {
+            mNoteId = Long.valueOf(intent.getData().getPathSegments().get(1));
+            mSnippet = DataUtils.getSnippetById(this.getContentResolver(), mNoteId);
+            //根据ID从数据库中获取标签的内容；
+            //getContentResolver（）是实现数据共享，实例存储。
+            mSnippet = mSnippet.length() > SNIPPET_PREW_MAX_LEN ? mSnippet.substring(0,
+                    SNIPPET_PREW_MAX_LEN) + getResources().getString(R.string.notelist_string_info)
+                    : mSnippet;
+            //判断标签片段是否达到符合长度
+        } catch (IllegalArgumentException e) {
+            e.printStackTrace();
+            return;
+        }
+        /*
+        try
+        {
+        	// 代码区
+        }
+        catch(Exception e)
+        {
+        	// 异常处理
+        }
+                     代码区如果有错误，就会返回所写异常的处理。*/
+        mPlayer = new MediaPlayer();
+        if (DataUtils.visibleInNoteDatabase(getContentResolver(), mNoteId, Notes.TYPE_NOTE)) {
+            showActionDialog();
+            //弹出对话框
+            playAlarmSound();
+            //闹钟提示音激发
+        } else {
+            finish();
+            //完成闹钟动作
+        }
+    }
+
+    private boolean isScreenOn() {
+        //判断屏幕是否锁屏，调用系统函数判断，最后返回值是布尔类型
+        PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
+        return pm.isScreenOn();
+    }
+
+    private void playAlarmSound() {
+        //闹钟提示音激发
+        Uri url = RingtoneManager.getActualDefaultRingtoneUri(this, RingtoneManager.TYPE_ALARM);
+        //调用系统的铃声管理URI，得到闹钟提示音
+        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);
+            //方法：setDataSource(Context context, Uri uri)
+            //解释：无返回值，设置多媒体数据来源【根据 Uri】
+            mPlayer.prepare();
+            //准备同步
+            mPlayer.setLooping(true);
+            //设置是否循环播放
+            mPlayer.start();
+            //开始播放
+        } catch (IllegalArgumentException e) {
+            // TODO Auto-generated catch block
+            e.printStackTrace();
+            //e.printStackTrace()函数功能是抛出异常， 还将显示出更深的调用信息
+            //System.out.println(e)，这个方法打印出异常，并且输出在哪里出现的异常
+        } 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);
+        //AlertDialog的构造方法全部是Protected的
+        //所以不能直接通过new一个AlertDialog来创建出一个AlertDialog。
+        //要创建一个AlertDialog，就要用到AlertDialog.Builder中的create()方法
+        //如这里的dialog就是新建了一个AlertDialog
+        dialog.setTitle(R.string.app_name);
+        //为对话框设置标题
+        dialog.setMessage(mSnippet);
+        //为对话框设置内容
+        dialog.setPositiveButton(R.string.notealert_ok, this);
+        //给对话框添加"Yes"按钮
+        if (isScreenOn()) {
+            dialog.setNegativeButton(R.string.notealert_enter, this);
+        }//对话框添加"No"按钮
+        dialog.show().setOnDismissListener(this);
+    }
+
+    public void onClick(DialogInterface dialog, int which) {
+        switch (which) {
+            //用which来选择click后下一步的操作
+            case DialogInterface.BUTTON_NEGATIVE:
+                //这是取消操作
+                Intent intent = new Intent(this, NoteEditActivity.class);
+                //实现两个类间的数据传输
+                intent.setAction(Intent.ACTION_VIEW);
+                //设置动作属性
+                intent.putExtra(Intent.EXTRA_UID, mNoteId);
+                //实现key-value对
+                //EXTRA_UID为key；mNoteId为键
+                startActivity(intent);
+                //开始动作
+                break;
+            default:
+                //这是确定操作
+                break;
+        }
+    }
+
+    public void onDismiss(DialogInterface dialog) {
+        //忽略
+        stopAlarmSound();
+        //停止闹钟声音
+        finish();
+        //完成该动作
+    }
+
+    private void stopAlarmSound() {
+        if (mPlayer != null) {
+            mPlayer.stop();
+            //停止播放
+            mPlayer.release();
+            //释放MediaPlayer对象
+            mPlayer = null;
+        }
+    }
+}

doc/data/ui-1000/AlarmInitReceiver.java

@@ -0,0 +1,56 @@
+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
+    };
+    //对数据库的操作，调用标签ID和闹钟时间
+    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();
+        //System.currentTimeMillis()产生一个当前的毫秒
+        //这个毫秒其实就是自1970年1月1日0时起的毫秒数
+        Cursor c = context.getContentResolver().query(Notes.CONTENT_NOTE_URI,
+                PROJECTION,
+                NoteColumns.ALERTED_DATE + ">? AND " + NoteColumns.TYPE + "=" + Notes.TYPE_NOTE,
+                new String[] { String.valueOf(currentDate) },
+                //将long变量currentDate转化为字符串
+                null);
+        //Cursor在这里的作用是通过查找数据库中的标签内容，找到和当前系统时间相等的标签
+
+        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();
+        }
+        //然而通过网上查找资料发现，对于闹钟机制的启动，通常需要上面的几个步骤
+        //如新建Intent、PendingIntent以及AlarmManager等
+        //这里就是根据数据库里的闹钟时间创建一个闹钟机制
+    }
+}

doc/data/ui-1000/AlarmReceiver.java

@@ -0,0 +1,19 @@
+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);
+        //启动AlarmAlertActivity
+        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+        //activity要存在于activity的栈中，而非activity的途径启动activity时必然不存在一个activity的栈
+        //所以要新起一个栈装入启动的activity
+        context.startActivity(intent);
+    }
+}
+//这是实现alarm这个功能最接近用户层的包，基于上面的两个包，
+//作用还需要深究但是对于setClass和addFlags的

doc/data/ui-1000/DateTimePicker.java

@@ -0,0 +1,491 @@
+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 {
+    //FrameLayout是布局模板之一
+    //所有的子元素全部在屏幕的右上方
+    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;
+    //初始化控件
+    private final NumberPicker mDateSpinner;
+    private final NumberPicker mHourSpinner;
+    private final NumberPicker mMinuteSpinner;
+    private final NumberPicker mAmPmSpinner;
+    //NumberPicker是数字选择器
+    //这里定义的四个变量全部是在设置闹钟时需要选择的变量（如日期、时、分、上午或者下午）
+    private Calendar mDate;
+    //定义了Calendar类型的变量mDate，用于操作时间
+    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();
+        }
+    };//OnValueChangeListener，这是时间改变监听器，这里主要是对日期的监听
+    //将现在日期的值传递给mDate；updateDateControl是同步操作
+
+    private NumberPicker.OnValueChangeListener mOnHourChangedListener = new NumberPicker.OnValueChangeListener() {
+        //这里是对 小时（Hour） 的监听
+        @Override
+        public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
+            boolean isDateChanged = false;
+            Calendar cal = Calendar.getInstance();
+            //声明一个Calendar的变量cal，便于后续的操作
+            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;
+                    //这里是对于12小时制时，晚上11点和12点交替时对日期的更改
+                } 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;
+                }
+                //这里是对于12小时制时，凌晨11点和12点交替时对日期的更改
+                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();
+                }//这里是对于12小时制时，中午11点和12点交替时对AM和PM的更改
+            } else {
+                if (oldVal == HOURS_IN_ALL_DAY - 1 && newVal == 0) {
+                    cal.setTimeInMillis(mDate.getTimeInMillis());
+                    cal.add(Calendar.DAY_OF_YEAR, 1);
+                    isDateChanged = true;
+                    //这里是对于24小时制时，晚上11点和12点交替时对日期的更改
+                } else if (oldVal == 0 && newVal == HOURS_IN_ALL_DAY - 1) {
+                    cal.setTimeInMillis(mDate.getTimeInMillis());
+                    cal.add(Calendar.DAY_OF_YEAR, -1);
+                    isDateChanged = true;
+                }
+            } //这里是对于12小时制时，凌晨11点和12点交替时对日期的更改
+            int newHour = mHourSpinner.getValue() % HOURS_IN_HALF_DAY + (mIsAm ? 0 : HOURS_IN_HALF_DAY);
+            //通过数字选择器对newHour的赋值
+            mDate.set(Calendar.HOUR_OF_DAY, newHour);
+            //通过set函数将新的Hour值传给mDate
+            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
+        //这里是对 分钟（Minute）改变的监听
+        public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
+            int minValue = mMinuteSpinner.getMinValue();
+            int maxValue = mMinuteSpinner.getMaxValue();
+            int offset = 0;
+            //设置offset，作为小时改变的一个记录数据
+            if (oldVal == maxValue && newVal == minValue) {
+                offset += 1;
+            } else if (oldVal == minValue && newVal == maxValue) {
+                offset -= 1;
+            }
+            //如果原值为59，新值为0，则offset加1
+            //如果原值为0，新值为59，则offset减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() {
+        //对AM和PM的监听
+        @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());
+    }//通过对数据库的访问，获取当前的系统时间
+
+    public DateTimePicker(Context context, long date) {
+        this(context, date, DateFormat.is24HourFormat(context));
+    }//上面函数的得到的是一个天文数字（1970至今的秒数），需要DateFormat将其变得有意义
+
+    public DateTimePicker(Context context, long date, boolean is24HourView) {
+        super(context);
+        //获取系统时间
+        mDate = Calendar.getInstance();
+        mInitialising = true;
+        mIsAm = getCurrentHourOfDay() >= HOURS_IN_HALF_DAY;
+        inflate(context, R.layout.datetime_picker, this);
+        //如果当前Activity里用到别的layout，比如对话框layout
+        //还要设置这个layout上的其他组件的内容，就必须用inflate()方法先将对话框的layout找出来
+        //然后再用findViewById()找到它上面的其它组件
+        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;
+    }
+    //存在疑问！！！！！！！！！！！！！setEnabled的作用
+    //下面的代码通过原程序的注释已经比较清晰，另外可以通过函数名来判断
+    //下面的各函数主要是对上面代码引用到的各函数功能的实现
+    @Override
+    public boolean isEnabled() {
+        return mIsEnabled;
+    }
+
+    /**
+     * Get the current date in millis
+     *
+     * @return the current date in millis
+     */
+    public long getCurrentDateInTimeMillis() {
+        return mDate.getTimeInMillis();
+    }//实现函数——得到当前的秒数
+
+    /**
+     * 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));
+    }//实现函数功能——设置当前的时间，参数是date
+
+    /**
+     * 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);
+    }//实现函数功能——设置当前的时间，参数是各详细的变量
+
+    /**
+     * Get current year
+     *
+     * @return The current year
+     */
+    //下面是得到year、month、day等值
+    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();
+    }// 对于星期几的算法
+
+    private void updateAmPmControl() {
+        if (mIs24HourView) {
+            mAmPmSpinner.setVisibility(View.GONE);
+        } else {
+            int index = mIsAm ? Calendar.AM : Calendar.PM;
+            mAmPmSpinner.setValue(index);
+            mAmPmSpinner.setVisibility(View.VISIBLE);
+        }// 对于上下午操作的算法
+    }
+
+    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);
+        }// 对与小时的算法
+    }
+
+    /**
+     * 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());
+        }
+    }
+}

doc/data/ui-1000/DateTimePickerDialog.java

@@ -0,0 +1,87 @@
+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();
+    //创建一个Calendar类型的变量 mDate，方便时间的操作
+    private boolean mIs24HourView;
+    private OnDateTimeSetListener mOnDateTimeSetListener;
+    //声明一个时间日期滚动选择控件 mOnDateTimeSetListener
+    private DateTimePicker mDateTimePicker;
+    //DateTimePicker控件，控件一般用于让用户可以从日期列表中选择单个值。
+    //运行时，单击控件边上的下拉箭头，会显示为两个部分：一个下拉列表，一个用于选择日期的
+
+    public interface OnDateTimeSetListener {
+        void OnDateTimeSet(AlertDialog dialog, long date);
+    }
+
+    public DateTimePickerDialog(Context context, long date) {
+        //对该界面对话框的实例化
+        super(context);
+        //对数据库的操作
+        mDateTimePicker = new DateTimePicker(context);
+        setView(mDateTimePicker);
+        //添加一个子视图
+        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);
+                //将视图中的各选项设置为系统当前时间
+                updateTitle(mDate.getTimeInMillis());
+            }
+        });
+        mDate.setTimeInMillis(date);
+        //得到系统时间
+        mDate.set(Calendar.SECOND, 0);
+        //将秒数设置为0
+        mDateTimePicker.setCurrentDate(mDate.getTimeInMillis());
+        setButton(context.getString(R.string.datetime_dialog_ok), this);
+        setButton2(context.getString(R.string.datetime_dialog_cancel), (OnClickListener)null);
+        //设置按钮
+        set24HourView(DateFormat.is24HourFormat(this.getContext()));
+        //时间标准化打印
+        updateTitle(mDate.getTimeInMillis());
+    }
+
+    public void set24HourView(boolean is24HourView) {
+        mIs24HourView = is24HourView;
+    }
+
+    public void setOnDateTimeSetListener(OnDateTimeSetListener callBack) {
+        mOnDateTimeSetListener = callBack;
+    }//将时间日期滚动选择控件实例化
+
+    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));
+    }//android开发中常见日期管理工具类（API）——DateUtils：按照上下午显示时间
+
+    public void onClick(DialogInterface arg0, int arg1) {
+        if (mOnDateTimeSetListener != null) {
+            mOnDateTimeSetListener.OnDateTimeSet(this, mDate.getTimeInMillis());
+        }
+    }//第一个参数arg0是接收到点击事件的对话框
+    //第二个参数arg1是该对话框上的按钮
+
+}

doc/data/ui-1000/DropdownMenu.java

@@ -0,0 +1,49 @@
+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;
+    //声明一个下拉菜单
+    private Menu mMenu;
+
+    public DropdownMenu(Context context, Button button, int menuId) {
+        mButton = button;
+        mButton.setBackgroundResource(R.drawable.dropdown_icon);
+        //设置这个view的背景
+        mPopupMenu = new PopupMenu(context, mButton);
+        mMenu = mPopupMenu.getMenu();
+        mPopupMenu.getMenuInflater().inflate(menuId, mMenu);
+        //MenuInflater是用来实例化Menu目录下的Menu布局文件
+        //根据ID来确认menu的内容选项
+        mButton.setOnClickListener(new OnClickListener() {
+            public void onClick(View v) {
+                mPopupMenu.show();
+            }
+        });
+    }
+
+    public void setOnDropdownMenuItemClickListener(OnMenuItemClickListener listener) {
+        if (mPopupMenu != null) {
+            mPopupMenu.setOnMenuItemClickListener(listener);
+        }//设置菜单的监听
+    }
+
+    public MenuItem findItem(int id) {
+        return mMenu.findItem(id);
+    }//对于菜单选项的初始化，根据索引搜索菜单需要的选项
+
+    public void setTitle(CharSequence title) {
+        mButton.setText(title);
+    }//布局文件，设置标题
+}

doc/data/ui-1000/FoldersListAdapter.java

@@ -0,0 +1,71 @@
+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 {
+    //CursorAdapter是Cursor和ListView的接口
+    //FoldersListAdapter继承了CursorAdapter的类
+    //主要作用是便签数据库和用户的交互
+    //这里就是用folder（文件夹）的形式展现给用户
+    public static final String [] PROJECTION = {
+            NoteColumns.ID,
+            NoteColumns.SNIPPET
+    };//调用数据库中便签的ID和片段
+
+    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
+    }//数据库操作
+
+    @Override
+    public View newView(Context context, Cursor cursor, ViewGroup parent) {
+        //ViewGroup是容器
+        return new FolderListItem(context);
+    }//创建一个文件夹，对于各文件夹中子标签的初始化
+
+    @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);
+        }
+    }//将各个布局文件绑定起来
+
+    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);
+    }//根据数据库中标签的ID得到标签的各项内容
+
+    private class FolderListItem extends LinearLayout {
+        private TextView mName;
+
+        public FolderListItem(Context context) {
+            super(context);
+            //操作数据库
+            inflate(context, R.layout.folder_list_item, this);
+            //根据布局文件的名字等信息将其找出来
+            mName = (TextView) findViewById(R.id.tv_folder_name);
+        }
+
+        public void bind(String name) {
+            mName.setText(name);
+        }
+    }
+
+}