diff --git a/.idea/deploymentTargetSelector.xml b/.idea/deploymentTargetSelector.xml
index b268ef3..e38da12 100644
--- a/.idea/deploymentTargetSelector.xml
+++ b/.idea/deploymentTargetSelector.xml
@@ -4,6 +4,14 @@
     <selectionStates>
       <SelectionState runConfigName="app">
         <option name="selectionMode" value="DROPDOWN" />
+        <DropdownSelection timestamp="2025-05-15T08:17:27.567875Z">
+          <Target type="DEFAULT_BOOT">
+            <handle>
+              <DeviceId pluginId="LocalEmulator" identifier="path=C:\Users\Lenovo\.android\avd\Medium_Phone.avd" />
+            </handle>
+          </Target>
+        </DropdownSelection>
+        <DialogSelection />
       </SelectionState>
     </selectionStates>
   </component>
diff --git a/app/build.gradle b/app/build.gradle
index ed80e36..3773198 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -53,9 +53,8 @@ android {
 }
 
 dependencies {
-    // 第三方库依赖管理（建议通过 libs 别名集中声明，位于 build.gradle.kts 或 settings.gradle）
+    // HTTP 客户端库（注意：Android 6.0+ 需动态申请网络权限）
 
-    // HTTP 客户端库（Apache HttpClient 4.5.14，注意：Android 6.0+ 需动态申请网络权限）
     implementation("org.apache.httpcomponents:httpclient:4.5.14")
 
     // AndroidX 支持库
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index beb3c10..bb09d7d 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -44,7 +44,7 @@
         android:label="@string/app_name"
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
-        android:theme="@style/Theme.Notesmaster"
+        android:theme="@style/Theme.AppCompat.Light.DarkActionBar"
         tools:targetApi="31">
 
         <!--
@@ -59,7 +59,7 @@
             android:configChanges="keyboardHidden|orientation|screenSize"
             android:label="@string/app_name"
             android:launchMode="singleTop"
-            android:theme="@style/NoteTheme"
+            android:theme="@style/Theme.AppCompat.Light.DarkActionBar"
             android:uiOptions="splitActionBarWhenNarrow"
             android:windowSoftInputMode="adjustPan"
             android:exported="true">
diff --git a/app/src/main/java/net/micode/notes/data/Contact.java b/app/src/main/java/net/micode/notes/data/Contact.java
index d97ac5d..283c3ed 100644
--- a/app/src/main/java/net/micode/notes/data/Contact.java
+++ b/app/src/main/java/net/micode/notes/data/Contact.java
@@ -1,17 +1,14 @@
 /*
- * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ * 版权声明 (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
+ * 本文件采用 Apache License, Version 2.0 许可
+ * 您可以在以下网址获取许可证副本:
  *
  *        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.
+ * 除非适用法律要求或书面同意，否则根据许可证分发的软件按"原样"分发
+ * 不附带任何形式的明示或暗示保证
+ * 有关许可证下的权限和限制，请参阅许可证文件
  */
 
 package net.micode.notes.data;
@@ -25,49 +22,73 @@ import android.util.Log;
 
 import java.util.HashMap;
 
+/**
+ * 联系人工具类 - 提供从手机联系人数据库查询电话号码对应的联系人姓名功能
+ * 实现了联系人查询结果的内存缓存，避免重复查询提高性能
+ */
 public class Contact {
+    // 联系人缓存：键为电话号码，值为对应的联系人姓名
     private static HashMap<String, String> sContactCache;
     private static final String TAG = "Contact";
 
+    // 联系人查询SQL模板：用于查找与给定电话号码匹配的联系人
+    // 使用 PHONE_NUMBERS_EQUAL 函数处理号码格式差异（如区号、国际前缀等）
     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 "
+            + ",?) AND " + Data.MIMETYPE + "='" + Phone.CONTENT_ITEM_TYPE + "'"
+            + " AND " + Data.RAW_CONTACT_ID + " IN "
             + "(SELECT raw_contact_id "
             + " FROM phone_lookup"
             + " WHERE min_match = '+')";
 
+    /**
+     * 根据电话号码查询联系人姓名（带缓存机制）
+     *
+     * @param context 应用上下文
+     * @param phoneNumber 待查询的电话号码
+     * @return 匹配的联系人姓名，如果未找到则返回null
+     */
     public static String getContact(Context context, String phoneNumber) {
+        // 初始化缓存
         if(sContactCache == null) {
             sContactCache = new HashMap<String, String>();
         }
 
+        // 优先从缓存中获取结果，提高性能
         if(sContactCache.containsKey(phoneNumber)) {
             return sContactCache.get(phoneNumber);
         }
 
+        // 构建动态查询条件（处理不同格式的电话号码）
         String selection = CALLER_ID_SELECTION.replace("+",
                 PhoneNumberUtils.toCallerIDMinMatch(phoneNumber));
+
+        // 查询联系人数据库
         Cursor cursor = context.getContentResolver().query(
-                Data.CONTENT_URI,
-                new String [] { Phone.DISPLAY_NAME },
-                selection,
-                new String[] { phoneNumber },
-                null);
+                Data.CONTENT_URI,               // 查询的URI（联系人数据）
+                new String [] { Phone.DISPLAY_NAME }, // 需要返回的字段（联系人姓名）
+                selection,                      // 查询条件
+                new String[] { phoneNumber },   // 查询参数
+                null);                          // 排序方式
 
+        // 处理查询结果
         if (cursor != null && cursor.moveToFirst()) {
             try {
+                // 获取联系人姓名并加入缓存
                 String name = cursor.getString(0);
                 sContactCache.put(phoneNumber, name);
                 return name;
             } catch (IndexOutOfBoundsException e) {
+                // 处理异常情况
                 Log.e(TAG, " Cursor get string error " + e.toString());
                 return null;
             } finally {
+                // 确保游标资源被释放
                 cursor.close();
             }
         } else {
+            // 未找到匹配的联系人
             Log.d(TAG, "No contact matched with number:" + phoneNumber);
             return null;
         }
     }
-}
+}
\ No newline at end of file
diff --git a/app/src/main/java/net/micode/notes/ui/NoteEditActivity.java b/app/src/main/java/net/micode/notes/ui/NoteEditActivity.java
index 96a9ff8..f2091d0 100644
--- a/app/src/main/java/net/micode/notes/ui/NoteEditActivity.java
+++ b/app/src/main/java/net/micode/notes/ui/NoteEditActivity.java
@@ -74,6 +74,7 @@ import java.util.regex.Pattern;
 
 public class NoteEditActivity extends Activity implements OnClickListener,
         NoteSettingChangedListener, OnTextViewChangeListener {
+
     private class HeadViewHolder {
         public TextView tvModified;
 
diff --git a/app/src/main/java/net/micode/notes/ui/NotesListActivity.java b/app/src/main/java/net/micode/notes/ui/NotesListActivity.java
index e843aec..492fcf6 100644
--- a/app/src/main/java/net/micode/notes/ui/NotesListActivity.java
+++ b/app/src/main/java/net/micode/notes/ui/NotesListActivity.java
@@ -60,6 +60,8 @@ import android.widget.PopupMenu;
 import android.widget.TextView;
 import android.widget.Toast;
 
+import androidx.appcompat.app.AppCompatActivity;
+
 import net.micode.notes.R;
 import net.micode.notes.data.Notes;
 import net.micode.notes.data.Notes.NoteColumns;
@@ -78,7 +80,8 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.util.HashSet;
 
-public class NotesListActivity extends Activity implements OnClickListener, OnItemLongClickListener {
+public class NotesListActivity extends AppCompatActivity implements OnClickListener, OnItemLongClickListener {
+    private int mode=-1;
     private static final int FOLDER_NOTE_LIST_QUERY_TOKEN = 0;
 
     private static final int FOLDER_LIST_QUERY_TOKEN      = 1;
@@ -139,6 +142,9 @@ public class NotesListActivity extends Activity implements OnClickListener, OnIt
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.note_list);
+
+        getWindow().setBackgroundDrawableResource(R.drawable.beijing);
+        getWindow().setBackgroundDrawableResource(R.drawable.bb);
         initResources();
 
         /**
@@ -775,12 +781,27 @@ public class NotesListActivity extends Activity implements OnClickListener, OnIt
         } else {
             Log.e(TAG, "Wrong state:" + mState);
         }
+
+        if(mode==-1)
+            menu.findItem(R.id.menu_beijing).setVisible(false);
+        else if(mode==0)
+            menu.findItem(R.id.menu_bb).setVisible(false);
         return true;
     }
 
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId()) {
+            case R.id.menu_beijing:{
+                mode=-1;
+                getWindow().setBackgroundDrawableResource(R.drawable.beijing);
+                break;
+            }
+            case R.id.menu_bb:{
+                mode=0;
+                getWindow().setBackgroundDrawableResource(R.drawable.bb);
+                break;
+            }
             case R.id.menu_new_folder: {
                 showCreateOrModifyFolderDialog(true);
                 break;
diff --git a/app/src/main/res/drawable/bb.png b/app/src/main/res/drawable/bb.png
new file mode 100644
index 0000000..a4cfd30
Binary files /dev/null and b/app/src/main/res/drawable/bb.png differ
diff --git a/app/src/main/res/drawable/beijing.png b/app/src/main/res/drawable/beijing.png
new file mode 100644
index 0000000..2a2a6ee
Binary files /dev/null and b/app/src/main/res/drawable/beijing.png differ
diff --git a/app/src/main/res/layout/note_list.xml b/app/src/main/res/layout/note_list.xml
index 6b25d38..23989cb 100644
--- a/app/src/main/res/layout/note_list.xml
+++ b/app/src/main/res/layout/note_list.xml
@@ -18,8 +18,8 @@
 <FrameLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="fill_parent"
-    android:layout_height="fill_parent"
-    android:background="@drawable/list_background">
+    android:layout_height="fill_parent">
+<!--    android:background="@drawable/list_background">-->
 
     <LinearLayout
         android:layout_width="fill_parent"
diff --git a/app/src/main/res/menu/note_list.xml b/app/src/main/res/menu/note_list.xml
index 42ea736..6d8b14b 100644
--- a/app/src/main/res/menu/note_list.xml
+++ b/app/src/main/res/menu/note_list.xml
@@ -36,4 +36,10 @@
     <item
         android:id="@+id/menu_search"
         android:title="@string/menu_search"/>
+    <item
+        android:id="@+id/menu_beijing"
+        android:title="@string/menu_beijing"/>
+    <item
+        android:id="@+id/menu_bb"
+        android:title="@string/menu_bb"/>
 </menu>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 55df868..6a316b5 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -120,6 +120,9 @@
     <string name="call_record_folder_name">Call notes</string>
     <string name="hint_foler_name">Input name</string>
 
+    <string name="menu_beijing">Background: beijing</string>
+    <string name="menu_bb">Background: bb</string>
+
     <string name="search_label">Searching Notes</string>
     <string name="search_hint">Search notes</string>
     <string name="search_setting_description">Text in your notes</string>
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index d750e65..448262c 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -49,7 +49,7 @@
     </style>
 
     <style name="HighlightTextAppearancePrimary">
-    <item name="android:textSize">@dimen/text_font_size_normal</item>
+        <item name="android:textSize">@dimen/text_font_size_normal</item>
         <item name="android:textColor">@color/primary_text_dark</item>
     </style>
 
@@ -66,4 +66,7 @@
         <item name="android:displayOptions" />
         <item name="android:visibility">gone</item>
     </style>
-</resources>
\ No newline at end of file
+</resources>
+    <!--<style name="NoteActionBarStyle" parent="@android:style/Widget.Holo.Light.ActionBar.Solid">-->
+    <!--    <item name="android:visibility">visible</item>-->
+    <!--</style>-->
\ No newline at end of file
diff --git a/settings.gradle b/settings.gradle
index 3720822..04a33b3 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -1,35 +1,59 @@
+// Gradle 插件管理配置
 pluginManagement {
+    // 定义插件解析时的仓库搜索顺序
     repositories {
+        // 阿里云 Maven 镜像 - 中央仓库
         maven { setUrl("https://maven.aliyun.com/repository/central") }
+        // 阿里云 Maven 镜像 - JCenter (已停止更新，仅用于兼容旧依赖)
         maven { setUrl("https://maven.aliyun.com/repository/jcenter") }
+        // 阿里云 Maven 镜像 - Google 官方仓库
         maven { setUrl("https://maven.aliyun.com/repository/google") }
+        // 阿里云 Maven 镜像 - Gradle 插件仓库
         maven { setUrl("https://maven.aliyun.com/repository/gradle-plugin") }
+        // 阿里云公共仓库 - 包含多个源的综合镜像
         maven { setUrl("https://maven.aliyun.com/repository/public") }
+        // JitPack - 用于直接从 GitHub 引用依赖
         maven { setUrl("https://jitpack.io") }
+
+        // Google 官方仓库，限定只搜索 Android 相关组件
         google {
             content {
-                includeGroupByRegex("com\\.android.*")
-                includeGroupByRegex("com\\.google.*")
-                includeGroupByRegex("androidx.*")
+                includeGroupByRegex("com\\.android.*")  // Android SDK 组件
+                includeGroupByRegex("com\\.google.*")  // Google 库和服务
+                includeGroupByRegex("androidx.*")     // AndroidX 组件
             }
         }
+
+        // Maven 中央仓库
         mavenCentral()
+        // Gradle 插件门户
         gradlePluginPortal()
     }
 }
+
+// 依赖解析管理配置
 dependencyResolutionManagement {
+    // 配置依赖解析模式：当项目中定义了仓库时会报错，强制统一使用 settings.gradle 中的仓库
     repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
+
+    // 定义项目依赖解析时的仓库搜索顺序
     repositories {
+        // 阿里云镜像仓库配置 (同 pluginManagement)
         maven { setUrl("https://maven.aliyun.com/repository/central") }
         maven { setUrl("https://maven.aliyun.com/repository/jcenter") }
         maven { setUrl("https://maven.aliyun.com/repository/google") }
         maven { setUrl("https://maven.aliyun.com/repository/gradle-plugin") }
         maven { setUrl("https://maven.aliyun.com/repository/public") }
         maven { setUrl("https://jitpack.io") }
+
+        // Google 官方仓库 (完整搜索范围)
         google()
+        // Maven 中央仓库
         mavenCentral()
     }
 }
 
+// 根项目名称
 rootProject.name = "Notes-master"
-include ':app'
+// 包含的子项目
+include ':app'
\ No newline at end of file