diff --git a/src/Notes-master/res/drawable/category_bg.xml b/src/Notes-master/res/drawable/category_bg.xml
new file mode 100644
index 0000000..f9419de
--- /dev/null
+++ b/src/Notes-master/res/drawable/category_bg.xml
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android">
+    <!-- 圆角矩形 -->
+    <corners android:radius="10dip" />
+    <!-- 背景颜色 -->
+    <solid android:color="#FF6666" />
+    <!-- 边框 -->
+    <stroke
+        android:width="1dip"
+        android:color="#FF4444" />
+</shape>
\ No newline at end of file
diff --git a/src/Notes-master/res/drawable/ic_launcher_background.xml b/src/Notes-master/res/drawable/ic_launcher_background.xml
new file mode 100644
index 0000000..07d5da9
--- /dev/null
+++ b/src/Notes-master/res/drawable/ic_launcher_background.xml
@@ -0,0 +1,170 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path
+        android:fillColor="#3DDC84"
+        android:pathData="M0,0h108v108h-108z" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M9,0L9,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,0L19,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,0L29,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,0L39,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,0L49,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,0L59,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,0L69,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,0L79,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M89,0L89,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M99,0L99,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,9L108,9"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,19L108,19"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,29L108,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,39L108,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,49L108,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,59L108,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,69L108,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,79L108,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,89L108,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,99L108,99"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,29L89,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,39L89,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,49L89,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,59L89,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,69L89,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,79L89,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,19L29,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,19L39,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,19L49,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,19L59,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,19L69,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,19L79,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+</vector>
diff --git a/src/Notes-master/res/drawable/ic_launcher_foreground.xml b/src/Notes-master/res/drawable/ic_launcher_foreground.xml
new file mode 100644
index 0000000..2b068d1
--- /dev/null
+++ b/src/Notes-master/res/drawable/ic_launcher_foreground.xml
@@ -0,0 +1,30 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path android:pathData="M31,63.928c0,0 6.4,-11 12.1,-13.1c7.2,-2.6 26,-1.4 26,-1.4l38.1,38.1L107,108.928l-32,-1L31,63.928z">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:endX="85.84757"
+                android:endY="92.4963"
+                android:startX="42.9492"
+                android:startY="49.59793"
+                android:type="linear">
+                <item
+                    android:color="#44000000"
+                    android:offset="0.0" />
+                <item
+                    android:color="#00000000"
+                    android:offset="1.0" />
+            </gradient>
+        </aapt:attr>
+    </path>
+    <path
+        android:fillColor="#FFFFFF"
+        android:fillType="nonZero"
+        android:pathData="M65.3,45.828l3.8,-6.6c0.2,-0.4 0.1,-0.9 -0.3,-1.1c-0.4,-0.2 -0.9,-0.1 -1.1,0.3l-3.9,6.7c-6.3,-2.8 -13.4,-2.8 -19.7,0l-3.9,-6.7c-0.2,-0.4 -0.7,-0.5 -1.1,-0.3C38.8,38.328 38.7,38.828 38.9,39.228l3.8,6.6C36.2,49.428 31.7,56.028 31,63.928h46C76.3,56.028 71.8,49.428 65.3,45.828zM43.4,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2c-0.3,-0.7 -0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C45.3,56.528 44.5,57.328 43.4,57.328L43.4,57.328zM64.6,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2s-0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C66.5,56.528 65.6,57.328 64.6,57.328L64.6,57.328z"
+        android:strokeWidth="1"
+        android:strokeColor="#00000000" />
+</vector>
\ No newline at end of file
diff --git a/src/Notes-master/res/drawable/mi_logo_background.xml b/src/Notes-master/res/drawable/mi_logo_background.xml
new file mode 100644
index 0000000..80c49d0
--- /dev/null
+++ b/src/Notes-master/res/drawable/mi_logo_background.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+    <solid android:color="#FF6200" />
+    <size
+        android:width="180dp"
+        android:height="180dp" />
+</shape>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/activity_friend_management.xml b/src/Notes-master/res/layout/activity_friend_management.xml
new file mode 100644
index 0000000..1a97657
--- /dev/null
+++ b/src/Notes-master/res/layout/activity_friend_management.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <ListView
+        android:id="@+id/friend_list"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:divider="@android:drawable/divider_horizontal_bright"
+        android:dividerHeight="1dp"
+        android:padding="8dp" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/activity_friend_note_edit.xml b/src/Notes-master/res/layout/activity_friend_note_edit.xml
new file mode 100644
index 0000000..6dcf460
--- /dev/null
+++ b/src/Notes-master/res/layout/activity_friend_note_edit.xml
@@ -0,0 +1,73 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <ScrollView
+        android:id="@+id/sv_note_edit"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:layout_weight="1">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="vertical">
+
+            <LinearLayout
+                android:id="@+id/note_title"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:padding="8dp"
+                android:background="@android:color/darker_gray">
+
+                <TextView
+                    android:id="@+id/tv_modified_date"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:textAppearance="@android:style/TextAppearance.Medium"
+                    android:textColor="@android:color/primary_text_light" />
+
+            </LinearLayout>
+
+            <!-- 标题显示区域 -->
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:padding="16dp"
+                android:background="@android:color/white">
+                <TextView
+                    android:id="@+id/note_title_view"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:textAppearance="@android:style/TextAppearance.Large"
+                    android:textColor="@android:color/primary_text_dark"
+                    android:textSize="20sp"
+                    android:gravity="center"
+                    android:paddingBottom="10dp"
+                    android:layout_marginBottom="10dp"
+                    android:fontFamily="sans-serif-medium"
+                    android:background="@null" />
+                <View
+                    android:layout_width="match_parent"
+                    android:layout_height="1dp"
+                    android:background="#CCCCCC" />
+            </LinearLayout>
+
+            <!-- 正文显示区域 -->
+            <TextView
+                android:id="@+id/note_edit_view"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:background="@android:color/white"
+                android:padding="16dp"
+                android:textAppearance="@android:style/TextAppearance.Medium"
+                android:textColor="@android:color/primary_text_dark"
+                android:textSize="16sp" />
+
+        </LinearLayout>
+
+    </ScrollView>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/activity_friend_note_list.xml b/src/Notes-master/res/layout/activity_friend_note_list.xml
new file mode 100644
index 0000000..39a42f7
--- /dev/null
+++ b/src/Notes-master/res/layout/activity_friend_note_list.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <ListView
+        android:id="@+id/friend_note_list"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:divider="@android:drawable/divider_horizontal_bright"
+        android:dividerHeight="1dp"
+        android:padding="8dp" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/activity_login.xml b/src/Notes-master/res/layout/activity_login.xml
new file mode 100644
index 0000000..69a0139
--- /dev/null
+++ b/src/Notes-master/res/layout/activity_login.xml
@@ -0,0 +1,147 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical"
+    android:gravity="center_horizontal"
+    android:padding="20dp"
+    android:background="@android:color/white">
+
+    <!-- 应用图标 -->
+    <ImageView
+        android:layout_width="100dp"
+        android:layout_height="100dp"
+        android:src="@mipmap/ic_launcher"
+        android:layout_marginBottom="30dp"
+        android:layout_marginTop="50dp" />
+
+    <!-- 应用名称 -->
+    <TextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="@string/app_name"
+        android:textSize="24sp"
+        android:textStyle="bold"
+        android:layout_marginBottom="40dp" />
+
+    <!-- 登录表单 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="vertical"
+        android:gravity="center_horizontal"
+        android:background="@android:color/white"
+        android:padding="20dp"
+        android:elevation="5dp"
+        android:layout_marginBottom="20dp">
+
+        <!-- 用户名输入 -->
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="horizontal"
+            android:gravity="center_vertical"
+            android:layout_marginBottom="15dp">
+
+            <TextView
+                android:layout_width="80dp"
+                android:layout_height="wrap_content"
+                android:text="用户名："
+                android:textSize="16sp" />
+
+            <EditText
+                android:id="@+id/et_username"
+                android:layout_width="match_parent"
+                android:layout_height="40dp"
+                android:hint="请输入用户名"
+                android:inputType="text"
+                android:singleLine="true"
+                android:background="@android:drawable/editbox_background_normal"
+                android:paddingLeft="10dp"
+                android:paddingRight="10dp" />
+        </LinearLayout>
+
+        <!-- 密码输入 -->
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="horizontal"
+            android:gravity="center_vertical"
+            android:layout_marginBottom="20dp">
+
+            <TextView
+                android:layout_width="80dp"
+                android:layout_height="wrap_content"
+                android:text="密码："
+                android:textSize="16sp" />
+
+            <EditText
+                android:id="@+id/et_password"
+                android:layout_width="match_parent"
+                android:layout_height="40dp"
+                android:hint="请输入密码"
+                android:inputType="textPassword"
+                android:singleLine="true"
+                android:background="@android:drawable/editbox_background_normal"
+                android:paddingLeft="10dp"
+                android:paddingRight="10dp" />
+        </LinearLayout>
+
+        <!-- 登录按钮 -->
+        <Button
+            android:id="@+id/btn_login"
+            android:layout_width="match_parent"
+            android:layout_height="45dp"
+            android:text="登录"
+            android:textSize="18sp"
+            android:textColor="@android:color/white"
+            android:background="@android:color/holo_orange_light"
+            android:layout_marginBottom="15dp"
+            android:onClick="onLoginClick" />
+
+        <!-- 注册和忘记密码按钮 -->
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="horizontal"
+            android:gravity="center_horizontal">
+
+            <Button
+                android:id="@+id/btn_register"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="注册账号"
+                android:textSize="14sp"
+                android:textColor="@android:color/holo_blue_dark"
+                android:background="@null"
+                android:onClick="onRegisterClick" />
+
+            <View
+                android:layout_width="1dp"
+                android:layout_height="20dp"
+                android:background="@android:color/darker_gray"
+                android:layout_marginLeft="20dp"
+                android:layout_marginRight="20dp" />
+
+            <Button
+                android:id="@+id/btn_change_password"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="修改密码"
+                android:textSize="14sp"
+                android:textColor="@android:color/holo_blue_dark"
+                android:background="@null"
+                android:onClick="onChangePasswordClick" />
+        </LinearLayout>
+    </LinearLayout>
+
+    <!-- 版权信息 -->
+    <TextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="© 2024 小米便签"
+        android:textSize="12sp"
+        android:textColor="@android:color/darker_gray"
+        android:layout_marginTop="50dp" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/activity_main.xml b/src/Notes-master/res/layout/activity_main.xml
new file mode 100644
index 0000000..86a5d97
--- /dev/null
+++ b/src/Notes-master/res/layout/activity_main.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".MainActivity">
+
+    <TextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="Hello World!"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/activity_splash.xml b/src/Notes-master/res/layout/activity_splash.xml
new file mode 100644
index 0000000..3e060a4
--- /dev/null
+++ b/src/Notes-master/res/layout/activity_splash.xml
@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:background="#FFFFFF"
+    android:gravity="center">
+
+    <!-- 小米官方logo: 橙色圆形背景白色MI字样 -->
+    <LinearLayout
+        android:id="@+id/mi_logo"
+        android:layout_width="180dp"
+        android:layout_height="180dp"
+        android:layout_centerInParent="true"
+        android:background="@drawable/mi_logo_background"
+        android:gravity="center"
+        android:orientation="vertical">
+
+        <!-- 使用TextView显示白色MI字样 -->
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="MI"
+            android:textColor="#FFFFFF"
+            android:textSize="120sp"
+            android:textStyle="bold"
+            android:fontFamily="sans-serif" />
+    </LinearLayout>
+
+    <!-- 移除应用名称，只保留logo -->
+</RelativeLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/chat_activity.xml b/src/Notes-master/res/layout/chat_activity.xml
new file mode 100644
index 0000000..33e4530
--- /dev/null
+++ b/src/Notes-master/res/layout/chat_activity.xml
@@ -0,0 +1,55 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="fill_parent"
+    android:layout_height="fill_parent"
+    android:orientation="vertical"
+    android:background="#f0f0f0">
+    
+    <!-- 聊天消息列表 -->
+    <ListView
+        android:id="@+id/chat_list"
+        android:layout_width="fill_parent"
+        android:layout_height="0dip"
+        android:layout_weight="1"
+        android:cacheColorHint="@null"
+        android:divider="@null"
+        android:dividerHeight="8dip"
+        android:padding="8dip"
+        android:scrollbars="vertical" />
+    
+    <!-- 输入框和发送按钮 -->
+    <LinearLayout
+        android:layout_width="fill_parent"
+        android:layout_height="wrap_content"
+        android:layout_gravity="bottom"
+        android:background="#ffffff"
+        android:orientation="horizontal"
+        android:padding="8dip"
+        android:weightSum="1">
+        
+        <EditText
+            android:id="@+id/message_edit_text"
+            android:layout_width="0dip"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center_vertical"
+            android:layout_weight="1"
+            android:background="@android:drawable/edit_text"
+            android:hint="输入消息..."
+            android:inputType="textMultiLine"
+            android:maxLines="3"
+            android:padding="8dip"
+            android:textColor="#000000"
+            android:textSize="16sp" />
+        
+        <Button
+            android:id="@+id/send_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center_vertical"
+            android:layout_marginLeft="8dip"
+            android:background="@android:drawable/btn_default"
+            android:text="发送"
+            android:textColor="#ffffff"
+            android:textSize="16sp" />
+    </LinearLayout>
+</LinearLayout>
diff --git a/src/Notes-master/res/layout/chat_message_received_item.xml b/src/Notes-master/res/layout/chat_message_received_item.xml
new file mode 100644
index 0000000..9dd9aa8
--- /dev/null
+++ b/src/Notes-master/res/layout/chat_message_received_item.xml
@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="fill_parent"
+    android:layout_height="wrap_content"
+    android:layout_gravity="left"
+    android:gravity="left"
+    android:orientation="vertical"
+    android:padding="4dip">
+    
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="left"
+        android:background="#ffffff"
+        android:orientation="vertical"
+        android:padding="8dip">
+        
+        <TextView
+            android:id="@+id/message_content"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="left"
+            android:maxWidth="250dip"
+            android:padding="4dip"
+            android:text="消息内容"
+            android:textColor="#000000"
+            android:textSize="16sp" />
+        
+        <TextView
+            android:id="@+id/message_time"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="left"
+            android:layout_marginTop="4dip"
+            android:padding="2dip"
+            android:text="12:00"
+            android:textColor="#80000000"
+            android:textSize="12sp" />
+    </LinearLayout>
+</LinearLayout>
diff --git a/src/Notes-master/res/layout/chat_message_received_note_item.xml b/src/Notes-master/res/layout/chat_message_received_note_item.xml
new file mode 100644
index 0000000..df3d62f
--- /dev/null
+++ b/src/Notes-master/res/layout/chat_message_received_note_item.xml
@@ -0,0 +1,70 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="fill_parent"
+    android:layout_height="wrap_content"
+    android:layout_gravity="left"
+    android:gravity="left"
+    android:orientation="vertical"
+    android:padding="4dip">
+    
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="left"
+        android:background="#ffffff"
+        android:orientation="vertical"
+        android:padding="8dip">
+        
+        <!-- 添加"便签"标注 -->
+        <LinearLayout
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="left"
+            android:orientation="horizontal"
+            android:gravity="center">
+            
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="[便签]"
+                android:textColor="#ffffff"
+                android:textSize="12sp"
+                android:background="@android:drawable/btn_default_small"
+                android:paddingLeft="6dip"
+                android:paddingRight="6dip"
+                android:paddingTop="2dip"
+                android:paddingBottom="2dip"
+                android:layout_marginRight="4dip"
+                android:backgroundTint="#0000ff" /> <!-- 接收的便签标注使用蓝色 -->
+                
+            <TextView
+                android:id="@+id/message_content"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_gravity="left"
+                android:maxWidth="300dip"
+                android:padding="4dip"
+                android:text="便签内容"
+                android:textColor="#000000"
+                android:textSize="16sp"
+                android:clickable="true"
+                android:focusable="true"
+                android:background="@android:drawable/btn_default_small"
+                android:paddingLeft="8dip"
+                android:paddingRight="8dip"
+                android:paddingTop="4dip"
+                android:paddingBottom="4dip" />
+        </LinearLayout> <!-- 闭合LinearLayout -->
+        
+        <TextView
+            android:id="@+id/message_time"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="left"
+            android:layout_marginTop="4dip"
+            android:padding="2dip"
+            android:text="12:00"
+            android:textColor="#80000000"
+            android:textSize="12sp" />
+    </LinearLayout>
+</LinearLayout>
diff --git a/src/Notes-master/res/layout/chat_message_sent_item.xml b/src/Notes-master/res/layout/chat_message_sent_item.xml
new file mode 100644
index 0000000..b9038fb
--- /dev/null
+++ b/src/Notes-master/res/layout/chat_message_sent_item.xml
@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="fill_parent"
+    android:layout_height="wrap_content"
+    android:layout_gravity="right"
+    android:gravity="right"
+    android:orientation="vertical"
+    android:padding="4dip">
+    
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="right"
+        android:background="@android:drawable/btn_default"
+        android:orientation="vertical"
+        android:padding="8dip">
+        
+        <TextView
+            android:id="@+id/message_content"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="right"
+            android:maxWidth="250dip"
+            android:padding="4dip"
+            android:text="消息内容"
+            android:textColor="#ffffff"
+            android:textSize="16sp" />
+        
+        <TextView
+            android:id="@+id/message_time"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="right"
+            android:layout_marginTop="4dip"
+            android:padding="2dip"
+            android:text="12:00"
+            android:textColor="#80ffffff"
+            android:textSize="12sp" />
+    </LinearLayout>
+</LinearLayout>
diff --git a/src/Notes-master/res/layout/chat_message_sent_note_item.xml b/src/Notes-master/res/layout/chat_message_sent_note_item.xml
new file mode 100644
index 0000000..3bb0c6f
--- /dev/null
+++ b/src/Notes-master/res/layout/chat_message_sent_note_item.xml
@@ -0,0 +1,70 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="fill_parent"
+    android:layout_height="wrap_content"
+    android:layout_gravity="right"
+    android:gravity="right"
+    android:orientation="vertical"
+    android:padding="4dip">
+    
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="right"
+        android:background="@android:drawable/btn_default"
+        android:orientation="vertical"
+        android:padding="8dip">
+        
+        <!-- 添加"便签"标注 -->
+        <LinearLayout
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="right"
+            android:orientation="horizontal"
+            android:gravity="center">
+            
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="[便签]"
+                android:textColor="#ffffff"
+                android:textSize="12sp"
+                android:background="@android:drawable/btn_default_small"
+                android:paddingLeft="6dip"
+                android:paddingRight="6dip"
+                android:paddingTop="2dip"
+                android:paddingBottom="2dip"
+                android:layout_marginRight="4dip"
+                android:backgroundTint="#ff0000" />
+                
+            <TextView
+                android:id="@+id/message_content"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_gravity="right"
+                android:maxWidth="300dip"
+                android:padding="4dip"
+                android:text="便签内容"
+                android:textColor="#ffffff"
+                android:textSize="16sp"
+                android:clickable="true"
+                android:focusable="true"
+                android:background="@android:drawable/btn_default_small"
+                android:paddingLeft="8dip"
+                android:paddingRight="8dip"
+                android:paddingTop="4dip"
+                android:paddingBottom="4dip" />
+        </LinearLayout> <!-- 闭合LinearLayout -->
+        
+        <TextView
+            android:id="@+id/message_time"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="right"
+            android:layout_marginTop="4dip"
+            android:padding="2dip"
+            android:text="12:00"
+            android:textColor="#80ffffff"
+            android:textSize="12sp" />
+    </LinearLayout>
+</LinearLayout>
diff --git a/src/Notes-master/res/layout/dialog_change_password.xml b/src/Notes-master/res/layout/dialog_change_password.xml
new file mode 100644
index 0000000..c8e703b
--- /dev/null
+++ b/src/Notes-master/res/layout/dialog_change_password.xml
@@ -0,0 +1,150 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical"
+    android:padding="20dp">
+
+    <!-- 标题 -->
+    <TextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="修改密码"
+        android:textSize="20sp"
+        android:textStyle="bold"
+        android:layout_gravity="center_horizontal"
+        android:layout_marginBottom="20dp" />
+
+    <!-- 用户名输入 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_vertical"
+        android:layout_marginBottom="15dp">
+
+        <TextView
+            android:layout_width="80dp"
+            android:layout_height="wrap_content"
+            android:text="用户名："
+            android:textSize="16sp" />
+
+        <EditText
+            android:id="@+id/et_change_username"
+            android:layout_width="match_parent"
+            android:layout_height="40dp"
+            android:hint="请输入用户名"
+            android:inputType="text"
+            android:singleLine="true"
+            android:background="@android:drawable/editbox_background_normal"
+            android:paddingLeft="10dp"
+            android:paddingRight="10dp" />
+    </LinearLayout>
+
+    <!-- 当前密码输入 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_vertical"
+        android:layout_marginBottom="15dp">
+
+        <TextView
+            android:layout_width="80dp"
+            android:layout_height="wrap_content"
+            android:text="当前密码："
+            android:textSize="16sp" />
+
+        <EditText
+            android:id="@+id/et_current_password"
+            android:layout_width="match_parent"
+            android:layout_height="40dp"
+            android:hint="请输入当前密码"
+            android:inputType="textPassword"
+            android:singleLine="true"
+            android:background="@android:drawable/editbox_background_normal"
+            android:paddingLeft="10dp"
+            android:paddingRight="10dp" />
+    </LinearLayout>
+
+    <!-- 新密码输入 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_vertical"
+        android:layout_marginBottom="15dp">
+
+        <TextView
+            android:layout_width="80dp"
+            android:layout_height="wrap_content"
+            android:text="新密码："
+            android:textSize="16sp" />
+
+        <EditText
+            android:id="@+id/et_new_password"
+            android:layout_width="match_parent"
+            android:layout_height="40dp"
+            android:hint="请输入新密码"
+            android:inputType="textPassword"
+            android:singleLine="true"
+            android:background="@android:drawable/editbox_background_normal"
+            android:paddingLeft="10dp"
+            android:paddingRight="10dp" />
+    </LinearLayout>
+
+    <!-- 确认新密码输入 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_vertical"
+        android:layout_marginBottom="20dp">
+
+        <TextView
+            android:layout_width="80dp"
+            android:layout_height="wrap_content"
+            android:text="确认新密码："
+            android:textSize="16sp" />
+
+        <EditText
+            android:id="@+id/et_confirm_new_password"
+            android:layout_width="match_parent"
+            android:layout_height="40dp"
+            android:hint="请再次输入新密码"
+            android:inputType="textPassword"
+            android:singleLine="true"
+            android:background="@android:drawable/editbox_background_normal"
+            android:paddingLeft="10dp"
+            android:paddingRight="10dp" />
+    </LinearLayout>
+
+    <!-- 按钮 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_horizontal"
+        android:layout_marginTop="10dp">
+
+        <Button
+            android:id="@+id/btn_change_cancel"
+            android:layout_width="wrap_content"
+            android:layout_height="40dp"
+            android:text="取消"
+            android:textSize="16sp"
+            android:textColor="@android:color/black"
+            android:background="@android:drawable/btn_default"
+            android:layout_marginRight="20dp" />
+
+        <Button
+            android:id="@+id/btn_change_confirm"
+            android:layout_width="wrap_content"
+            android:layout_height="40dp"
+            android:text="确认修改"
+            android:textSize="16sp"
+            android:textColor="@android:color/white"
+            android:background="@android:color/holo_orange_light" />
+    </LinearLayout>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/dialog_register.xml b/src/Notes-master/res/layout/dialog_register.xml
new file mode 100644
index 0000000..a4d2243
--- /dev/null
+++ b/src/Notes-master/res/layout/dialog_register.xml
@@ -0,0 +1,124 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical"
+    android:padding="20dp">
+
+    <!-- 标题 -->
+    <TextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="注册账号"
+        android:textSize="20sp"
+        android:textStyle="bold"
+        android:layout_gravity="center_horizontal"
+        android:layout_marginBottom="20dp" />
+
+    <!-- 用户名输入 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_vertical"
+        android:layout_marginBottom="15dp">
+
+        <TextView
+            android:layout_width="80dp"
+            android:layout_height="wrap_content"
+            android:text="用户名："
+            android:textSize="16sp" />
+
+        <EditText
+            android:id="@+id/et_register_username"
+            android:layout_width="match_parent"
+            android:layout_height="40dp"
+            android:hint="请输入用户名"
+            android:inputType="text"
+            android:singleLine="true"
+            android:background="@android:drawable/editbox_background_normal"
+            android:paddingLeft="10dp"
+            android:paddingRight="10dp" />
+    </LinearLayout>
+
+    <!-- 密码输入 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_vertical"
+        android:layout_marginBottom="15dp">
+
+        <TextView
+            android:layout_width="80dp"
+            android:layout_height="wrap_content"
+            android:text="密码："
+            android:textSize="16sp" />
+
+        <EditText
+            android:id="@+id/et_register_password"
+            android:layout_width="match_parent"
+            android:layout_height="40dp"
+            android:hint="请输入密码"
+            android:inputType="textPassword"
+            android:singleLine="true"
+            android:background="@android:drawable/editbox_background_normal"
+            android:paddingLeft="10dp"
+            android:paddingRight="10dp" />
+    </LinearLayout>
+
+    <!-- 确认密码输入 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_vertical"
+        android:layout_marginBottom="20dp">
+
+        <TextView
+            android:layout_width="80dp"
+            android:layout_height="wrap_content"
+            android:text="确认密码："
+            android:textSize="16sp" />
+
+        <EditText
+            android:id="@+id/et_register_confirm_password"
+            android:layout_width="match_parent"
+            android:layout_height="40dp"
+            android:hint="请再次输入密码"
+            android:inputType="textPassword"
+            android:singleLine="true"
+            android:background="@android:drawable/editbox_background_normal"
+            android:paddingLeft="10dp"
+            android:paddingRight="10dp" />
+    </LinearLayout>
+
+    <!-- 按钮 -->
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_horizontal"
+        android:layout_marginTop="10dp">
+
+        <Button
+            android:id="@+id/btn_register_cancel"
+            android:layout_width="wrap_content"
+            android:layout_height="40dp"
+            android:text="取消"
+            android:textSize="16sp"
+            android:textColor="@android:color/black"
+            android:background="@android:drawable/btn_default"
+            android:layout_marginRight="20dp" />
+
+        <Button
+            android:id="@+id/btn_register_confirm"
+            android:layout_width="wrap_content"
+            android:layout_height="40dp"
+            android:text="注册"
+            android:textSize="16sp"
+            android:textColor="@android:color/white"
+            android:background="@android:color/holo_orange_light" />
+    </LinearLayout>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/item_friend.xml b/src/Notes-master/res/layout/item_friend.xml
new file mode 100644
index 0000000..bfd61f0
--- /dev/null
+++ b/src/Notes-master/res/layout/item_friend.xml
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical"
+    android:padding="16dp">
+
+    <TextView
+        android:id="@+id/friend_username"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:textAppearance="@android:style/TextAppearance.Medium"
+        android:textColor="@android:color/primary_text_light"
+        android:textSize="16sp" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/password_input_dialog.xml b/src/Notes-master/res/layout/password_input_dialog.xml
new file mode 100644
index 0000000..826ab01
--- /dev/null
+++ b/src/Notes-master/res/layout/password_input_dialog.xml
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical"
+    android:padding="16dp">
+
+    <EditText
+        android:id="@+id/password_input"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:inputType="textPassword"
+        android:hint="@string/preferences_new_password_hint"
+        android:layout_marginBottom="16dp" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/layout/password_setting_dialog.xml b/src/Notes-master/res/layout/password_setting_dialog.xml
new file mode 100644
index 0000000..ebc749f
--- /dev/null
+++ b/src/Notes-master/res/layout/password_setting_dialog.xml
@@ -0,0 +1,52 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical"
+    android:padding="16dp">
+
+    <TextView
+        android:id="@+id/current_password_label"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="@string/preferences_current_password_label"
+        android:layout_marginBottom="8dp" />
+
+    <EditText
+        android:id="@+id/current_password"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:inputType="textPassword"
+        android:hint="@string/preferences_current_password_hint"
+        android:layout_marginBottom="16dp" />
+
+    <TextView
+        android:id="@+id/new_password_label"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="@string/preferences_new_password_label"
+        android:layout_marginBottom="8dp" />
+
+    <EditText
+        android:id="@+id/new_password"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:inputType="textPassword"
+        android:hint="@string/preferences_new_password_hint"
+        android:layout_marginBottom="16dp" />
+
+    <TextView
+        android:id="@+id/confirm_password_label"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="@string/preferences_confirm_password_label"
+        android:layout_marginBottom="8dp" />
+
+    <EditText
+        android:id="@+id/confirm_password"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:inputType="textPassword"
+        android:hint="@string/preferences_confirm_password_hint" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/src/Notes-master/res/mipmap-anydpi/ic_launcher.xml b/src/Notes-master/res/mipmap-anydpi/ic_launcher.xml
new file mode 100644
index 0000000..6f3b755
--- /dev/null
+++ b/src/Notes-master/res/mipmap-anydpi/ic_launcher.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background" />
+    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+</adaptive-icon>
\ No newline at end of file
diff --git a/src/Notes-master/res/mipmap-anydpi/ic_launcher_round.xml b/src/Notes-master/res/mipmap-anydpi/ic_launcher_round.xml
new file mode 100644
index 0000000..6f3b755
--- /dev/null
+++ b/src/Notes-master/res/mipmap-anydpi/ic_launcher_round.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background" />
+    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+</adaptive-icon>
\ No newline at end of file
diff --git a/src/Notes-master/res/mipmap-hdpi/ic_launcher.webp b/src/Notes-master/res/mipmap-hdpi/ic_launcher.webp
new file mode 100644
index 0000000..c209e78
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diff --git a/src/Notes-master/res/mipmap-hdpi/ic_launcher_round.webp b/src/Notes-master/res/mipmap-hdpi/ic_launcher_round.webp
new file mode 100644
index 0000000..b2dfe3d
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diff --git a/src/Notes-master/res/mipmap-mdpi/ic_launcher.webp b/src/Notes-master/res/mipmap-mdpi/ic_launcher.webp
new file mode 100644
index 0000000..4f0f1d6
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diff --git a/src/Notes-master/res/mipmap-mdpi/ic_launcher_round.webp b/src/Notes-master/res/mipmap-mdpi/ic_launcher_round.webp
new file mode 100644
index 0000000..62b611d
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diff --git a/src/Notes-master/res/mipmap-xhdpi/ic_launcher.webp b/src/Notes-master/res/mipmap-xhdpi/ic_launcher.webp
new file mode 100644
index 0000000..948a307
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diff --git a/src/Notes-master/res/mipmap-xhdpi/ic_launcher_round.webp b/src/Notes-master/res/mipmap-xhdpi/ic_launcher_round.webp
new file mode 100644
index 0000000..1b9a695
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diff --git a/src/Notes-master/res/mipmap-xxhdpi/ic_launcher.webp b/src/Notes-master/res/mipmap-xxhdpi/ic_launcher.webp
new file mode 100644
index 0000000..28d4b77
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diff --git a/src/Notes-master/res/mipmap-xxhdpi/ic_launcher_round.webp b/src/Notes-master/res/mipmap-xxhdpi/ic_launcher_round.webp
new file mode 100644
index 0000000..9287f50
Binary files /dev/null and b/src/Notes-master/res/mipmap-xxhdpi/ic_launcher_round.webp differ
diff --git a/src/Notes-master/res/mipmap-xxxhdpi/ic_launcher.webp b/src/Notes-master/res/mipmap-xxxhdpi/ic_launcher.webp
new file mode 100644
index 0000000..aa7d642
Binary files /dev/null and b/src/Notes-master/res/mipmap-xxxhdpi/ic_launcher.webp differ
diff --git a/src/Notes-master/res/mipmap-xxxhdpi/ic_launcher_round.webp b/src/Notes-master/res/mipmap-xxxhdpi/ic_launcher_round.webp
new file mode 100644
index 0000000..9126ae3
Binary files /dev/null and b/src/Notes-master/res/mipmap-xxxhdpi/ic_launcher_round.webp differ
diff --git a/src/Notes-master/res/values-night/themes.xml b/src/Notes-master/res/values-night/themes.xml
new file mode 100644
index 0000000..d2c68d1
--- /dev/null
+++ b/src/Notes-master/res/values-night/themes.xml
@@ -0,0 +1,7 @@
+<resources xmlns:tools="http://schemas.android.com/tools">
+    <!-- Base application theme. -->
+    <style name="Base.Theme.Notesmaster" parent="Theme.Material3.DayNight.NoActionBar">
+        <!-- Customize your dark theme here. -->
+        <!-- <item name="colorPrimary">@color/my_dark_primary</item> -->
+    </style>
+</resources>
\ No newline at end of file
diff --git a/src/Notes-master/res/values/themes.xml b/src/Notes-master/res/values/themes.xml
new file mode 100644
index 0000000..7c616ff
--- /dev/null
+++ b/src/Notes-master/res/values/themes.xml
@@ -0,0 +1,9 @@
+<resources xmlns:tools="http://schemas.android.com/tools">
+    <!-- Base application theme. -->
+    <style name="Base.Theme.Notesmaster" parent="Theme.Material3.DayNight.NoActionBar">
+        <!-- Customize your light theme here. -->
+        <!-- <item name="colorPrimary">@color/my_light_primary</item> -->
+    </style>
+
+    <style name="Theme.Notesmaster" parent="Base.Theme.Notesmaster" />
+</resources>
\ No newline at end of file
diff --git a/src/Notes-master/res/xml/backup_rules.xml b/src/Notes-master/res/xml/backup_rules.xml
new file mode 100644
index 0000000..4df9255
--- /dev/null
+++ b/src/Notes-master/res/xml/backup_rules.xml
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample backup rules file; uncomment and customize as necessary.
+   See https://developer.android.com/guide/topics/data/autobackup
+   for details.
+   Note: This file is ignored for devices older than API 31
+   See https://developer.android.com/about/versions/12/backup-restore
+-->
+<full-backup-content>
+    <!--
+   <include domain="sharedpref" path="."/>
+   <exclude domain="sharedpref" path="device.xml"/>
+-->
+</full-backup-content>
\ No newline at end of file
diff --git a/src/Notes-master/res/xml/data_extraction_rules.xml b/src/Notes-master/res/xml/data_extraction_rules.xml
new file mode 100644
index 0000000..9ee9997
--- /dev/null
+++ b/src/Notes-master/res/xml/data_extraction_rules.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample data extraction rules file; uncomment and customize as necessary.
+   See https://developer.android.com/about/versions/12/backup-restore#xml-changes
+   for details.
+-->
+<data-extraction-rules>
+    <cloud-backup>
+        <!-- TODO: Use <include> and <exclude> to control what is backed up.
+        <include .../>
+        <exclude .../>
+        -->
+    </cloud-backup>
+    <!--
+    <device-transfer>
+        <include .../>
+        <exclude .../>
+    </device-transfer>
+    -->
+</data-extraction-rules>
\ No newline at end of file
diff --git a/src/Notes-master/src/net/micode/notes/data/Messages.java b/src/Notes-master/src/net/micode/notes/data/Messages.java
new file mode 100644
index 0000000..d6f2629
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/data/Messages.java
@@ -0,0 +1,23 @@
+package net.micode.notes.data;
+
+public class Messages {
+    
+    public interface MessageColumns {
+        public static final String ID = "id";
+        public static final String SENDER_ID = "sender_id";
+        public static final String RECEIVER_ID = "receiver_id";
+        public static final String CONTENT = "content";
+        public static final String MESSAGE_TYPE = "message_type";
+        public static final String CREATED_DATE = "created_date";
+        public static final String IS_READ = "is_read";
+    }
+    
+    public interface MessageType {
+        public static final int TEXT = 0;
+        public static final int IMAGE = 1;
+        public static final int EMOTION = 2;
+        public static final int NOTE = 3;
+    }
+    
+    public static final long ID_INVALID = -1;
+}
diff --git a/src/Notes-master/src/net/micode/notes/data/Users.java b/src/Notes-master/src/net/micode/notes/data/Users.java
new file mode 100644
index 0000000..1ba7b7f
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/data/Users.java
@@ -0,0 +1,31 @@
+/*
+ * 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;
+
+public class Users {
+    public interface UserColumns {
+        public static final String ID = "_id";
+        public static final String USERNAME = "username";
+        public static final String PASSWORD = "password";
+        public static final String CREATED_DATE = "created_date";
+        public static final String MODIFIED_DATE = "modified_date";
+    }
+
+    public interface UserConstants {
+        // 可以添加一些用户相关的常量
+    }
+}
\ No newline at end of file
diff --git a/src/Notes-master/src/net/micode/notes/tool/CategoryUtil.java b/src/Notes-master/src/net/micode/notes/tool/CategoryUtil.java
new file mode 100644
index 0000000..54c6bad
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/tool/CategoryUtil.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.tool;
+
+import android.text.TextUtils;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.regex.Pattern;
+
+/**
+ * 便签自动分类工具类
+ */
+public class CategoryUtil {
+    // 分类关键词映射表
+    private static final Map<String, String> CATEGORY_KEYWORDS = new HashMap<>();
+
+    static {
+        // 工作相关
+        addKeywords("工作", "工作", "任务", "项目", "会议", "报告", "加班", "上班", "下班", "同事", "领导", "客户", "公司");
+
+        // 学习相关
+        addKeywords("学习", "学习", "考试", "作业", "复习", "预习", "课程", "老师", "学生", "学校", "教材", "笔记", "知识点");
+
+        // 生活相关
+        addKeywords("生活", "生活", "日常", "购物", "吃饭", "旅游", "电影", "音乐", "健身", "运动", "休息", "睡觉", "起床");
+
+        // 想法相关
+        addKeywords("想法", "想法", "创意", "灵感", "思考", "感悟", "心得", "体会", "观点", "意见", "建议");
+
+        // 待办相关
+        addKeywords("待办", "待办", "todo", "需要", "必须", "应该", "计划", "安排", "准备");
+
+        // 其他默认分类
+        addKeywords("其他", "");
+    }
+
+    // 批量添加关键词
+    private static void addKeywords(String category, String... keywords) {
+        for (String keyword : keywords) {
+            CATEGORY_KEYWORDS.put(keyword, category);
+        }
+    }
+
+    /**
+     * 根据便签内容自动分类
+     * @param content 便签内容
+     * @return 分类结果，不超过3个字符
+     */
+    public static String autoCategorize(String content) {
+        if (TextUtils.isEmpty(content)) {
+            return "其他";
+        }
+
+        // 转为小写进行匹配
+        String lowerContent = content.toLowerCase();
+
+        // 遍历关键词，匹配分类
+        for (Map.Entry<String, String> entry : CATEGORY_KEYWORDS.entrySet()) {
+            String keyword = entry.getKey();
+            String category = entry.getValue();
+
+            // 跳过空关键词（默认分类）
+            if (TextUtils.isEmpty(keyword)) {
+                continue;
+            }
+
+            // 关键词匹配
+            if (lowerContent.contains(keyword.toLowerCase())) {
+                return category;
+            }
+        }
+
+        // 默认分类
+        return "其他";
+    }
+}
\ No newline at end of file
diff --git a/src/Notes-master/src/net/micode/notes/tool/UserManager.java b/src/Notes-master/src/net/micode/notes/tool/UserManager.java
new file mode 100644
index 0000000..1254109
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/tool/UserManager.java
@@ -0,0 +1,192 @@
+/*
+ * 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;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.util.Log;
+import net.micode.notes.data.NotesDatabaseHelper;
+import net.micode.notes.data.Users;
+
+/**
+ * 用户管理类，用于保存和获取当前登录用户的信息
+ */
+public class UserManager {
+    private static final String TAG = "UserManager";
+    private static final String PREF_NAME = "user_preferences";
+    private static final String KEY_CURRENT_USER_ID = "current_user_id";
+    private static final String KEY_CURRENT_USERNAME = "current_username";
+
+    private static UserManager sInstance;
+    private SharedPreferences mPrefs;
+    private Context mContext;
+
+    private UserManager(Context context) {
+        mContext = context.getApplicationContext();
+        mPrefs = mContext.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
+    }
+
+    public static synchronized UserManager getInstance(Context context) {
+        if (sInstance == null) {
+            sInstance = new UserManager(context);
+        }
+        return sInstance;
+    }
+
+    /**
+     * 保存当前登录用户的信息
+     * @param userId 用户ID
+     * @param username 用户名
+     */
+    public void saveCurrentUser(long userId, String username) {
+        SharedPreferences.Editor editor = mPrefs.edit();
+        editor.putLong(KEY_CURRENT_USER_ID, userId);
+        editor.putString(KEY_CURRENT_USERNAME, username);
+        editor.apply();
+    }
+
+    /**
+     * 获取当前登录用户的ID
+     * @return 当前用户ID，未登录返回-1
+     */
+    public long getCurrentUserId() {
+        return mPrefs.getLong(KEY_CURRENT_USER_ID, -1);
+    }
+
+    /**
+     * 获取当前登录用户的用户名
+     * @return 当前用户名，未登录返回null
+     */
+    public String getCurrentUsername() {
+        return mPrefs.getString(KEY_CURRENT_USERNAME, null);
+    }
+
+    /**
+     * 清除当前用户信息，用于退出登录
+     */
+    public void clearCurrentUser() {
+        SharedPreferences.Editor editor = mPrefs.edit();
+        editor.remove(KEY_CURRENT_USER_ID);
+        editor.remove(KEY_CURRENT_USERNAME);
+        editor.apply();
+    }
+
+    /**
+     * 检查是否已登录
+     * @return 是否已登录
+     */
+    public boolean isLoggedIn() {
+        return getCurrentUserId() != -1;
+    }
+    
+    /**
+     * 验证用户密码
+     * @param userId 用户ID
+     * @param password 输入的密码
+     * @return 密码是否正确
+     */
+    public boolean validatePassword(long userId, String password) {
+        try {
+            // 直接访问数据库验证密码
+            NotesDatabaseHelper helper = NotesDatabaseHelper.getInstance(mContext);
+            SQLiteDatabase db = helper.getReadableDatabase();
+            
+            Cursor cursor = null;
+            try {
+                String selection = Users.UserColumns.ID + " = ? AND " + Users.UserColumns.PASSWORD + " = ?";
+                String[] selectionArgs = {String.valueOf(userId), password};
+                
+                cursor = db.query(
+                        NotesDatabaseHelper.TABLE.USER,
+                        new String[]{Users.UserColumns.ID},
+                        selection,
+                        selectionArgs,
+                        null,
+                        null,
+                        null
+                );
+                
+                return cursor != null && cursor.moveToFirst();
+            } finally {
+                if (cursor != null) {
+                    cursor.close();
+                }
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+            return false;
+        }
+    }
+    
+    /**
+     * 设置当前用户
+     * @param userId 用户ID
+     */
+    public void setCurrentUser(long userId) {
+        try {
+            // 查询用户的用户名
+            NotesDatabaseHelper helper = NotesDatabaseHelper.getInstance(mContext);
+            SQLiteDatabase db = helper.getReadableDatabase();
+            
+            Cursor cursor = null;
+            String username = "未知用户";
+            try {
+                String selection = Users.UserColumns.ID + " = ?";
+                String[] selectionArgs = {String.valueOf(userId)};
+                
+                cursor = db.query(
+                        NotesDatabaseHelper.TABLE.USER,
+                        new String[]{Users.UserColumns.USERNAME},
+                        selection,
+                        selectionArgs,
+                        null,
+                        null,
+                        null
+                );
+                
+                if (cursor != null && cursor.moveToFirst()) {
+                    username = cursor.getString(0);
+                }
+            } finally {
+                if (cursor != null) {
+                    cursor.close();
+                }
+            }
+            
+            // 保存当前用户信息
+            SharedPreferences.Editor editor = mPrefs.edit();
+            editor.putLong(KEY_CURRENT_USER_ID, userId);
+            editor.putString(KEY_CURRENT_USERNAME, username);
+            editor.apply();
+        } catch (Exception e) {
+            Log.e(TAG, "Error in setCurrentUser: " + e.getMessage());
+            e.printStackTrace();
+            // 即使发生异常，也确保保存用户ID，避免状态不一致
+            try {
+                SharedPreferences.Editor editor = mPrefs.edit();
+                editor.putLong(KEY_CURRENT_USER_ID, userId);
+                editor.putString(KEY_CURRENT_USERNAME, "未知用户");
+                editor.apply();
+            } catch (Exception innerE) {
+                Log.e(TAG, "Error in emergency save: " + innerE.getMessage());
+                innerE.printStackTrace();
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Notes-master/src/net/micode/notes/ui/ChatActivity.java b/src/Notes-master/src/net/micode/notes/ui/ChatActivity.java
new file mode 100644
index 0000000..3f35133
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/ui/ChatActivity.java
@@ -0,0 +1,432 @@
+package net.micode.notes.ui;
+
+import android.app.ActionBar;
+import android.app.Activity;
+import android.app.AlertDialog;
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.os.Bundle;
+import android.util.Log;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.BaseAdapter;
+import android.widget.Button;
+import android.widget.EditText;
+import android.widget.ListView;
+import android.widget.TextView;
+import android.widget.Toast;
+import android.text.TextUtils;
+import android.graphics.Color;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Messages;
+import net.micode.notes.data.NotesDatabaseHelper;
+import net.micode.notes.tool.UserManager;
+
+import java.text.SimpleDateFormat;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+
+public class ChatActivity extends Activity {
+    private static final String TAG = "ChatActivity";
+    
+    private ListView mChatListView;
+    private EditText mMessageEditText;
+    private Button mSendButton;
+    private ChatAdapter mChatAdapter;
+    private List<ChatMessage> mMessageList;
+    
+    private NotesDatabaseHelper mDbHelper;
+    private SQLiteDatabase mDb;
+    private UserManager mUserManager;
+    
+    private long mCurrentUserId;
+    private long mFriendId;
+    private String mFriendUsername;
+    
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        
+        try {
+            setContentView(R.layout.chat_activity);
+            
+            // 设置ActionBar
+            ActionBar actionBar = getActionBar();
+            if (actionBar != null) {
+                actionBar.setDisplayHomeAsUpEnabled(true);
+            }
+            
+            // 获取Intent参数
+            mFriendId = getIntent().getLongExtra("friend_id", -1);
+            mFriendUsername = getIntent().getStringExtra("friend_username");
+            
+            if (mFriendId == -1 || mFriendUsername == null) {
+                Toast.makeText(this, "无效的好友信息", Toast.LENGTH_SHORT).show();
+                finish();
+                return;
+            }
+            
+            // 设置ActionBar标题为好友用户名
+            if (actionBar != null) {
+                actionBar.setTitle(mFriendUsername);
+            }
+            
+            // 初始化数据库
+            mDbHelper = NotesDatabaseHelper.getInstance(this);
+            if (mDbHelper != null) {
+                mDb = mDbHelper.getWritableDatabase();
+            }
+            
+            // 初始化UserManager
+            mUserManager = UserManager.getInstance(this);
+            if (mUserManager != null) {
+                mCurrentUserId = mUserManager.getCurrentUserId();
+            }
+            
+            // 初始化界面控件
+            mChatListView = findViewById(R.id.chat_list);
+            mMessageEditText = findViewById(R.id.message_edit_text);
+            mSendButton = findViewById(R.id.send_button);
+            
+            // 初始化消息列表
+            mMessageList = new ArrayList<>();
+            mChatAdapter = new ChatAdapter(this, mMessageList, mCurrentUserId);
+            mChatListView.setAdapter(mChatAdapter);
+            
+            // 设置发送按钮点击事件
+            mSendButton.setOnClickListener(new View.OnClickListener() {
+                @Override
+                public void onClick(View v) {
+                    sendMessage();
+                }
+            });
+            
+            // 加载聊天记录
+            loadChatHistory();
+        } catch (Exception e) {
+            Log.e(TAG, "Error in onCreate: " + e.getMessage(), e);
+            Toast.makeText(this, "聊天界面初始化失败", Toast.LENGTH_SHORT).show();
+            finish();
+        }
+    }
+    
+    @Override
+    protected void onResume() {
+        super.onResume();
+        
+        try {
+            // 重新获取当前用户ID，确保在账号切换后能使用正确的用户ID
+            if (mUserManager != null) {
+                mCurrentUserId = mUserManager.getCurrentUserId();
+                Log.d(TAG, "Updated current user ID to: " + mCurrentUserId);
+            }
+            
+            // 更新适配器的当前用户ID
+            if (mChatAdapter != null) {
+                mChatAdapter.mCurrentUserId = mCurrentUserId;
+            }
+            
+            // 重新加载聊天记录
+            loadChatHistory();
+        } catch (Exception e) {
+            Log.e(TAG, "Error in onResume: " + e.getMessage(), e);
+        }
+    }
+    
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        // 关闭数据库连接
+        if (mDb != null && mDb.isOpen()) {
+            mDb.close();
+        }
+    }
+    
+    @Override
+    public boolean onOptionsItemSelected(android.view.MenuItem item) {
+        switch (item.getItemId()) {
+            case android.R.id.home:
+                // 返回上一级活动
+                finish();
+                return true;
+            default:
+                return super.onOptionsItemSelected(item);
+        }
+    }
+    
+    /**
+     * 加载聊天记录
+     */
+    private void loadChatHistory() {
+        mMessageList.clear();
+        
+        // 查询聊天记录
+        String sql = "SELECT * FROM " + NotesDatabaseHelper.TABLE.MESSAGE + " WHERE " +
+                "(" + Messages.MessageColumns.SENDER_ID + " = ? AND " + Messages.MessageColumns.RECEIVER_ID + " = ?) OR " +
+                "(" + Messages.MessageColumns.SENDER_ID + " = ? AND " + Messages.MessageColumns.RECEIVER_ID + " = ?) " +
+                "ORDER BY " + Messages.MessageColumns.CREATED_DATE + " ASC";
+        
+        Cursor cursor = mDb.rawQuery(sql, new String[]{
+                String.valueOf(mCurrentUserId), String.valueOf(mFriendId),
+                String.valueOf(mFriendId), String.valueOf(mCurrentUserId)
+        });
+        
+        if (cursor != null) {
+            while (cursor.moveToNext()) {
+                long id = cursor.getLong(cursor.getColumnIndexOrThrow(Messages.MessageColumns.ID));
+                long senderId = cursor.getLong(cursor.getColumnIndexOrThrow(Messages.MessageColumns.SENDER_ID));
+                long receiverId = cursor.getLong(cursor.getColumnIndexOrThrow(Messages.MessageColumns.RECEIVER_ID));
+                String content = cursor.getString(cursor.getColumnIndexOrThrow(Messages.MessageColumns.CONTENT));
+                int messageType = cursor.getInt(cursor.getColumnIndexOrThrow(Messages.MessageColumns.MESSAGE_TYPE));
+                long createdDate = cursor.getLong(cursor.getColumnIndexOrThrow(Messages.MessageColumns.CREATED_DATE));
+                int isRead = cursor.getInt(cursor.getColumnIndexOrThrow(Messages.MessageColumns.IS_READ));
+                
+                mMessageList.add(new ChatMessage(id, senderId, receiverId, content, messageType, createdDate, isRead));
+            }
+            cursor.close();
+        }
+        
+        // 通知适配器数据变化
+        mChatAdapter.notifyDataSetChanged();
+        
+        // 滚动到底部
+        if (!mMessageList.isEmpty()) {
+            mChatListView.setSelection(mMessageList.size() - 1);
+        }
+        
+        // 将接收到的消息标记为已读
+        markMessagesAsRead();
+    }
+    
+    /**
+     * 发送消息
+     */
+    private void sendMessage() {
+        String content = mMessageEditText.getText().toString().trim();
+        if (content.isEmpty()) {
+            Toast.makeText(this, "消息内容不能为空", Toast.LENGTH_SHORT).show();
+            return;
+        }
+        
+        // 创建消息对象
+        ContentValues values = new ContentValues();
+        values.put(Messages.MessageColumns.SENDER_ID, mCurrentUserId);
+        values.put(Messages.MessageColumns.RECEIVER_ID, mFriendId);
+        values.put(Messages.MessageColumns.CONTENT, content);
+        values.put(Messages.MessageColumns.MESSAGE_TYPE, Messages.MessageType.TEXT);
+        values.put(Messages.MessageColumns.CREATED_DATE, System.currentTimeMillis());
+        values.put(Messages.MessageColumns.IS_READ, 0);
+        
+        // 插入消息到数据库
+        long messageId = mDb.insert(NotesDatabaseHelper.TABLE.MESSAGE, null, values);
+        if (messageId != -1) {
+            // 清空输入框
+            mMessageEditText.setText("");
+            
+            // 重新加载聊天记录
+            loadChatHistory();
+        } else {
+            Toast.makeText(this, "发送失败", Toast.LENGTH_SHORT).show();
+            Log.e(TAG, "Failed to send message");
+        }
+    }
+    
+    /**
+     * 将接收到的消息标记为已读
+     */
+    private void markMessagesAsRead() {
+        ContentValues values = new ContentValues();
+        values.put(Messages.MessageColumns.IS_READ, 1);
+        
+        int updatedRows = mDb.update(NotesDatabaseHelper.TABLE.MESSAGE, values,
+                Messages.MessageColumns.SENDER_ID + " = ? AND " + Messages.MessageColumns.RECEIVER_ID + " = ? AND " + Messages.MessageColumns.IS_READ + " = 0",
+                new String[]{String.valueOf(mFriendId), String.valueOf(mCurrentUserId)});
+        
+        Log.d(TAG, "Marked " + updatedRows + " messages as read");
+    }
+    
+    /**
+     * 显示便签详情
+     */
+    private void showNoteDetail(String noteData) {
+        try {
+            // 解析便签数据
+            String[] noteParts = noteData.split("\\|");
+            if (noteParts.length < 2) {
+                Toast.makeText(this, "无效的便签数据", Toast.LENGTH_SHORT).show();
+                return;
+            }
+            
+            String noteTitle = noteParts[0];
+            String noteContent = noteParts[1];
+            
+            if (TextUtils.isEmpty(noteTitle)) {
+                noteTitle = "无标题便签";
+            }
+            
+            // 创建并显示便签详情对话框
+            AlertDialog.Builder builder = new AlertDialog.Builder(this);
+            builder.setTitle(noteTitle);
+            builder.setMessage(noteContent);
+            builder.setPositiveButton("确定", null);
+            builder.show();
+        } catch (Exception e) {
+            Log.e(TAG, "Error showing note detail: " + e.getMessage(), e);
+            Toast.makeText(this, "显示便签详情失败", Toast.LENGTH_SHORT).show();
+        }
+    }
+    
+    /**
+     * 聊天消息实体类
+     */
+    private static class ChatMessage {
+        long id;
+        long senderId;
+        long receiverId;
+        String content;
+        int messageType;
+        long createdDate;
+        int isRead;
+        
+        ChatMessage(long id, long senderId, long receiverId, String content, int messageType, long createdDate, int isRead) {
+            this.id = id;
+            this.senderId = senderId;
+            this.receiverId = receiverId;
+            this.content = content;
+            this.messageType = messageType;
+            this.createdDate = createdDate;
+            this.isRead = isRead;
+        }
+    }
+    
+    /**
+     * 聊天消息适配器
+     */
+    private static class ChatAdapter extends BaseAdapter {
+        private static final int VIEW_TYPE_SENT_TEXT = 0;
+        private static final int VIEW_TYPE_RECEIVED_TEXT = 1;
+        private static final int VIEW_TYPE_SENT_NOTE = 2;
+        private static final int VIEW_TYPE_RECEIVED_NOTE = 3;
+        
+        private Context mContext;
+        private List<ChatMessage> mMessageList;
+        public long mCurrentUserId;
+        private LayoutInflater mInflater;
+        private SimpleDateFormat mDateFormat;
+        
+        ChatAdapter(Context context, List<ChatMessage> messageList, long currentUserId) {
+            mContext = context;
+            mMessageList = messageList;
+            mCurrentUserId = currentUserId;
+            mInflater = LayoutInflater.from(context);
+            mDateFormat = new SimpleDateFormat("HH:mm");
+        }
+        
+        @Override
+        public int getCount() {
+            return mMessageList.size();
+        }
+        
+        @Override
+        public Object getItem(int position) {
+            return mMessageList.get(position);
+        }
+        
+        @Override
+        public long getItemId(int position) {
+            return position;
+        }
+        
+        @Override
+        public int getViewTypeCount() {
+            return 4; // 四种视图类型：发送文本、接收文本、发送便签、接收便签
+        }
+        
+        @Override
+        public int getItemViewType(int position) {
+            ChatMessage message = mMessageList.get(position);
+            boolean isSentByMe = message.senderId == mCurrentUserId;
+            if (message.messageType == Messages.MessageType.NOTE) {
+                return isSentByMe ? VIEW_TYPE_SENT_NOTE : VIEW_TYPE_RECEIVED_NOTE;
+            } else {
+                return isSentByMe ? VIEW_TYPE_SENT_TEXT : VIEW_TYPE_RECEIVED_TEXT;
+            }
+        }
+        
+        @Override
+        public View getView(int position, View convertView, ViewGroup parent) {
+            ChatMessage message = mMessageList.get(position);
+            boolean isSentByMe = message.senderId == mCurrentUserId;
+            
+            ViewHolder holder;
+            if (convertView == null) {
+                // 根据视图类型选择不同的布局
+                int viewType = getItemViewType(position);
+                switch (viewType) {
+                    case VIEW_TYPE_SENT_NOTE:
+                        convertView = mInflater.inflate(R.layout.chat_message_sent_note_item, parent, false);
+                        break;
+                    case VIEW_TYPE_RECEIVED_NOTE:
+                        convertView = mInflater.inflate(R.layout.chat_message_received_note_item, parent, false);
+                        break;
+                    case VIEW_TYPE_SENT_TEXT:
+                    default:
+                        convertView = mInflater.inflate(R.layout.chat_message_sent_item, parent, false);
+                        break;
+                    case VIEW_TYPE_RECEIVED_TEXT:
+                        convertView = mInflater.inflate(R.layout.chat_message_received_item, parent, false);
+                        break;
+                }
+                
+                holder = new ViewHolder();
+                holder.contentTextView = convertView.findViewById(R.id.message_content);
+                holder.timeTextView = convertView.findViewById(R.id.message_time);
+                convertView.setTag(holder);
+            } else {
+                holder = (ViewHolder) convertView.getTag();
+            }
+            
+            // 设置消息内容
+            if (message.messageType == Messages.MessageType.NOTE) {
+                // 便签类型消息，只显示便签标题
+                String[] noteData = message.content.split("\\|");
+                if (noteData.length >= 2) {
+                    String noteTitle = noteData[0];
+                    if (TextUtils.isEmpty(noteTitle)) {
+                        noteTitle = "无标题便签";
+                    }
+                    holder.contentTextView.setText(noteTitle);
+                    // 设置不同的颜色，区分于普通文本消息
+                    holder.contentTextView.setTextColor(Color.BLUE); // 使用蓝色区分便签消息
+                    holder.contentTextView.setOnClickListener(new View.OnClickListener() {
+                        @Override
+                        public void onClick(View v) {
+                            // 点击便签，查看详情
+                            ((ChatActivity) mContext).showNoteDetail(message.content);
+                        }
+                    });
+                }
+            } else {
+                // 普通文本消息
+                holder.contentTextView.setText(message.content);
+                holder.contentTextView.setOnClickListener(null);
+            }
+            
+            // 设置消息时间
+            Date date = new Date(message.createdDate);
+            holder.timeTextView.setText(mDateFormat.format(date));
+            
+            return convertView;
+        }
+        
+        private static class ViewHolder {
+            TextView contentTextView;
+            TextView timeTextView;
+        }
+    }
+}
diff --git a/src/Notes-master/src/net/micode/notes/ui/FriendManagementActivity.java b/src/Notes-master/src/net/micode/notes/ui/FriendManagementActivity.java
new file mode 100644
index 0000000..679971d
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/ui/FriendManagementActivity.java
@@ -0,0 +1,206 @@
+package net.micode.notes.ui;
+
+import android.app.ActionBar;
+import android.app.Activity;
+import android.content.Context;
+import android.content.Intent;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.AdapterView;
+import android.widget.BaseAdapter;
+import android.widget.ListView;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import net.micode.notes.R;
+import net.micode.notes.data.NotesDatabaseHelper;
+import net.micode.notes.tool.UserManager;
+import net.micode.notes.data.Users;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class FriendManagementActivity extends Activity {
+    private ListView mFriendListView;
+    private FriendAdapter mFriendAdapter;
+    private List<Friend> mFriendList;
+    private NotesDatabaseHelper mDbHelper;
+    private SQLiteDatabase mDb;
+    private UserManager mUserManager;
+    private long mCurrentUserId;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_friend_management);
+
+        // 设置ActionBar
+        ActionBar actionBar = getActionBar();
+        if (actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+            actionBar.setTitle("好友管理");
+        }
+
+        // 初始化数据库
+        mDbHelper = NotesDatabaseHelper.getInstance(this);
+        mDb = mDbHelper.getWritableDatabase();
+
+        // 初始化UserManager
+        mUserManager = UserManager.getInstance(this);
+        mCurrentUserId = mUserManager.getCurrentUserId();
+
+        // 初始化ListView
+        mFriendListView = findViewById(R.id.friend_list);
+        mFriendList = new ArrayList<>();
+        mFriendAdapter = new FriendAdapter(this, mFriendList);
+        mFriendListView.setAdapter(mFriendAdapter);
+
+        // 设置ListView点击事件
+        mFriendListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
+            @Override
+            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
+                Friend friend = mFriendList.get(position);
+                // 启动与好友聊天的活动
+                Intent intent = new Intent(FriendManagementActivity.this, ChatActivity.class);
+                intent.putExtra("friend_id", friend.id);
+                intent.putExtra("friend_username", friend.username);
+                startActivity(intent);
+            }
+        });
+
+        // 加载好友列表
+        loadFriendList();
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        // 重新加载好友列表
+        loadFriendList();
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        // 关闭数据库连接
+        if (mDb != null && mDb.isOpen()) {
+            mDb.close();
+        }
+    }
+
+    /**
+     * 加载好友列表，即除当前用户以外的所有用户
+     */
+    private void loadFriendList() {
+        mFriendList.clear();
+
+        // 查询除当前用户以外的所有用户
+        Cursor cursor = mDb.query(
+                NotesDatabaseHelper.TABLE.USER,
+                new String[]{Users.UserColumns.ID, Users.UserColumns.USERNAME},
+                Users.UserColumns.ID + " != ?",
+                new String[]{String.valueOf(mCurrentUserId)},
+                null,
+                null,
+                null
+        );
+
+        if (cursor != null) {
+            while (cursor.moveToNext()) {
+                long id = cursor.getLong(cursor.getColumnIndexOrThrow(Users.UserColumns.ID));
+                String username = cursor.getString(cursor.getColumnIndexOrThrow(Users.UserColumns.USERNAME));
+                mFriendList.add(new Friend(id, username));
+            }
+            cursor.close();
+        }
+
+        // 通知适配器数据变化
+        mFriendAdapter.notifyDataSetChanged();
+
+        // 如果没有好友，显示提示
+        if (mFriendList.isEmpty()) {
+            Toast.makeText(this, "暂无其他用户", Toast.LENGTH_SHORT).show();
+        }
+    }
+
+    /**
+     * 好友实体类
+     */
+    private static class Friend {
+        long id;
+        String username;
+
+        Friend(long id, String username) {
+            this.id = id;
+            this.username = username;
+        }
+    }
+
+    /**
+     * 好友列表适配器
+     */
+    private static class FriendAdapter extends BaseAdapter {
+        private Context mContext;
+        private List<Friend> mFriendList;
+        private LayoutInflater mInflater;
+
+        FriendAdapter(Context context, List<Friend> friendList) {
+            mContext = context;
+            mFriendList = friendList;
+            mInflater = LayoutInflater.from(context);
+        }
+
+        @Override
+        public int getCount() {
+            return mFriendList.size();
+        }
+
+        @Override
+        public Object getItem(int position) {
+            return mFriendList.get(position);
+        }
+
+        @Override
+        public long getItemId(int position) {
+            return position;
+        }
+
+        @Override
+        public View getView(int position, View convertView, ViewGroup parent) {
+            ViewHolder holder;
+            if (convertView == null) {
+                convertView = mInflater.inflate(R.layout.item_friend, parent, false);
+                holder = new ViewHolder();
+                holder.usernameTextView = convertView.findViewById(R.id.friend_username);
+                convertView.setTag(holder);
+            } else {
+                holder = (ViewHolder) convertView.getTag();
+            }
+
+            Friend friend = mFriendList.get(position);
+            holder.usernameTextView.setText(friend.username);
+
+            return convertView;
+        }
+
+        private static class ViewHolder {
+            TextView usernameTextView;
+        }
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(android.view.MenuItem item) {
+        switch (item.getItemId()) {
+            case android.R.id.home:
+                // 返回上一级活动
+                finish();
+                return true;
+            default:
+                return super.onOptionsItemSelected(item);
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Notes-master/src/net/micode/notes/ui/FriendNoteEditActivity.java b/src/Notes-master/src/net/micode/notes/ui/FriendNoteEditActivity.java
new file mode 100644
index 0000000..d5c6620
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/ui/FriendNoteEditActivity.java
@@ -0,0 +1,239 @@
+package net.micode.notes.ui;
+
+import android.app.ActionBar;
+import android.app.Activity;
+import android.content.Intent;
+import android.os.Bundle;
+import android.view.Menu;
+import android.view.View;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes;
+
+
+public class FriendNoteEditActivity extends Activity {
+    private TextView mNoteEditor;
+    private TextView mNoteTitleView;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_friend_note_edit);
+
+        // 设置ActionBar
+        ActionBar actionBar = getActionBar();
+        if (actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+            actionBar.setTitle("查看便签");
+        }
+
+        // 初始化控件
+        mNoteEditor = findViewById(R.id.note_edit_view);
+        mNoteTitleView = findViewById(R.id.note_title_view);
+
+        // 加载便签数据
+        if (savedInstanceState == null && !initActivityState(getIntent())) {
+            finish();
+            return;
+        }
+        initNoteScreen();
+    }
+
+    @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));
+            intent.putExtra("friend_id", savedInstanceState.getLong("friend_id"));
+            if (!initActivityState(intent)) {
+                finish();
+                return;
+            }
+            // 恢复状态后重新初始化界面
+            initNoteScreen();
+        }
+    }
+    
+    @Override
+    protected void onSaveInstanceState(Bundle outState) {
+        super.onSaveInstanceState(outState);
+        if (getIntent() != null) {
+            outState.putLong(Intent.EXTRA_UID, getIntent().getLongExtra(Intent.EXTRA_UID, 0));
+            outState.putLong("friend_id", getIntent().getLongExtra("friend_id", -1));
+        }
+    }
+
+    private String mNoteContent;
+    private String mNoteTitle;
+    private long mModifiedDate;
+    
+    private boolean initActivityState(Intent intent) {
+        /**
+         * 只支持查看模式
+         */
+        long noteId = intent.getLongExtra(Intent.EXTRA_UID, 0);
+        long friendId = intent.getLongExtra("friend_id", -1);
+        
+        if (noteId <= 0 || friendId <= 0) {
+            Toast.makeText(this, "便签信息错误", Toast.LENGTH_SHORT).show();
+            finish();
+            return false;
+        }
+
+        try {
+            // 查询便签基本信息，包括标题
+            String[] noteProjection = {
+                    net.micode.notes.data.Notes.NoteColumns.MODIFIED_DATE,
+                    net.micode.notes.data.Notes.NoteColumns.TITLE
+            };
+            
+            android.database.Cursor noteCursor = null;
+            try {
+                // 使用ContentResolver查询便签基本信息
+                noteCursor = getContentResolver().query(
+                        android.content.ContentUris.withAppendedId(net.micode.notes.data.Notes.CONTENT_NOTE_URI, noteId),
+                        noteProjection,
+                        null,
+                        null,
+                        null
+                );
+                
+                if (noteCursor != null) {
+                    if (noteCursor.moveToFirst()) {
+                        mModifiedDate = noteCursor.getLong(0);
+                        mNoteTitle = noteCursor.getString(1);
+                    }
+                    noteCursor.close();
+                }
+            } catch (Exception e) {
+                e.printStackTrace();
+                Toast.makeText(this, "查询便签信息失败", Toast.LENGTH_SHORT).show();
+            }
+            
+            // 查询便签具体内容，这是必须的，因为完整内容存储在Data表中
+            String[] dataProjection = {net.micode.notes.data.Notes.DataColumns.CONTENT};
+            String dataSelection = net.micode.notes.data.Notes.DataColumns.NOTE_ID + " = ? AND " + 
+                                 net.micode.notes.data.Notes.DataColumns.MIME_TYPE + " = ?";
+            String[] dataSelectionArgs = {String.valueOf(noteId), net.micode.notes.data.Notes.DataConstants.NOTE};
+            
+            android.database.Cursor dataCursor = null;
+            try {
+                // 使用ContentResolver查询数据
+                dataCursor = getContentResolver().query(
+                        net.micode.notes.data.Notes.CONTENT_DATA_URI,
+                        dataProjection,
+                        dataSelection,
+                        dataSelectionArgs,
+                        null
+                );
+                
+                if (dataCursor != null) {
+                    if (dataCursor.moveToFirst()) {
+                        mNoteContent = dataCursor.getString(0);
+                    }
+                    dataCursor.close();
+                }
+            } catch (Exception e) {
+                e.printStackTrace();
+                Toast.makeText(this, "查询便签内容失败", Toast.LENGTH_SHORT).show();
+            } finally {
+                if (dataCursor != null) {
+                    dataCursor.close();
+                }
+            }
+            
+            // 如果查询失败，尝试使用数据库直接查询
+            if (mNoteContent == null || mNoteContent.isEmpty()) {
+                try {
+                    // 直接使用数据库查询，绕过ContentProvider的用户过滤
+                    net.micode.notes.data.NotesDatabaseHelper helper = net.micode.notes.data.NotesDatabaseHelper.getInstance(FriendNoteEditActivity.this);
+                    if (helper != null) {
+                        dataCursor = helper.getReadableDatabase().query(
+                                net.micode.notes.data.NotesDatabaseHelper.TABLE.DATA,
+                                dataProjection,
+                                dataSelection,
+                                dataSelectionArgs,
+                                null,
+                                null,
+                                null
+                        );
+                        
+                        if (dataCursor != null) {
+                            if (dataCursor.moveToFirst()) {
+                                mNoteContent = dataCursor.getString(0);
+                            }
+                            dataCursor.close();
+                        }
+                    }
+                } catch (Exception e) {
+                    e.printStackTrace();
+                    Toast.makeText(this, "直接查询便签内容失败", Toast.LENGTH_SHORT).show();
+                } finally {
+                    if (dataCursor != null) {
+                        dataCursor.close();
+                    }
+                }
+            }
+            
+        } catch (Exception e) {
+            e.printStackTrace();
+            Toast.makeText(this, "初始化便签失败: " + e.getMessage(), Toast.LENGTH_SHORT).show();
+            finish();
+            return false;
+        }
+        return true;
+    }
+
+    private void initNoteScreen() {
+        // 显示修改日期
+        TextView modifiedDateTextView = findViewById(R.id.tv_modified_date);
+        modifiedDateTextView.setText(android.text.format.DateUtils.formatDateTime(
+                this, mModifiedDate, 
+                android.text.format.DateUtils.FORMAT_SHOW_DATE | 
+                        android.text.format.DateUtils.FORMAT_NUMERIC_DATE | 
+                        android.text.format.DateUtils.FORMAT_SHOW_TIME));
+        
+        // 显示便签标题
+        if (mNoteTitle != null && !mNoteTitle.isEmpty()) {
+            mNoteTitleView.setVisibility(View.VISIBLE);
+            mNoteTitleView.setText(mNoteTitle);
+        } else {
+            // 如果没有标题，隐藏标题文本视图
+            mNoteTitleView.setVisibility(View.GONE);
+        }
+        
+        // 显示便签内容，添加调试日志
+        if (mNoteContent != null && !mNoteContent.isEmpty()) {
+            mNoteEditor.setText(mNoteContent);
+            // 设置文本颜色为深色，确保可见
+            mNoteEditor.setTextColor(getResources().getColor(android.R.color.primary_text_dark));
+            // 设置背景色为白色，确保可见
+            mNoteEditor.setBackgroundColor(getResources().getColor(android.R.color.white));
+        } else {
+            // 如果内容为空，显示提示文本
+            mNoteEditor.setText("（空便签）");
+            mNoteEditor.setTextColor(getResources().getColor(android.R.color.secondary_text_dark));
+        }
+    }
+
+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        // 不显示菜单，因为是只读模式
+        return false;
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(android.view.MenuItem item) {
+        switch (item.getItemId()) {
+            case android.R.id.home:
+                // 返回上一级活动
+                finish();
+                return true;
+            default:
+                return super.onOptionsItemSelected(item);
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Notes-master/src/net/micode/notes/ui/FriendNoteListActivity.java b/src/Notes-master/src/net/micode/notes/ui/FriendNoteListActivity.java
new file mode 100644
index 0000000..6a381eb
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/ui/FriendNoteListActivity.java
@@ -0,0 +1,271 @@
+package net.micode.notes.ui;
+
+import android.app.ActionBar;
+import android.app.Activity;
+import android.content.Intent;
+import android.database.Cursor;
+import android.net.Uri;
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.AdapterView;
+import android.widget.BaseAdapter;
+import android.widget.ImageView;
+import android.widget.ListView;
+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.model.WorkingNote;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class FriendNoteListActivity extends Activity {
+    private ListView mNoteListView;
+    private NoteAdapter mNoteAdapter;
+    private List<Note> mNoteList;
+    private long mFriendId;
+    private String mFriendUsername;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_friend_note_list);
+
+        // 获取好友信息
+        mFriendId = getIntent().getLongExtra("friend_id", -1);
+        mFriendUsername = getIntent().getStringExtra("friend_username");
+
+        if (mFriendId == -1 || mFriendUsername == null) {
+            Toast.makeText(this, "好友信息错误", Toast.LENGTH_SHORT).show();
+            finish();
+            return;
+        }
+
+        // 设置ActionBar
+        ActionBar actionBar = getActionBar();
+        if (actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+            actionBar.setTitle(mFriendUsername + "的公开便签");
+        }
+
+        // 初始化ListView
+        mNoteListView = findViewById(R.id.friend_note_list);
+        mNoteList = new ArrayList<>();
+        mNoteAdapter = new NoteAdapter(this, mNoteList);
+        mNoteListView.setAdapter(mNoteAdapter);
+
+        // 设置ListView点击事件
+        mNoteListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
+            @Override
+            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
+                Note note = mNoteList.get(position);
+                // 启动查看便签详情的活动
+                Intent intent = new Intent(FriendNoteListActivity.this, FriendNoteEditActivity.class);
+                intent.putExtra(Intent.EXTRA_UID, note.id);
+                intent.putExtra("friend_id", mFriendId);
+                startActivity(intent);
+            }
+        });
+
+        // 加载好友的公开便签
+        loadFriendNotes();
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        // 重新加载好友便签
+        loadFriendNotes();
+    }
+
+    /**
+     * 加载好友的公开便签
+     */
+    private void loadFriendNotes() {
+        try {
+            mNoteList.clear();
+
+            // 查询好友的所有公开便签
+            String[] projection = {
+                    NoteColumns.ID,
+                    NoteColumns.TITLE,
+                    NoteColumns.SNIPPET,
+                    NoteColumns.MODIFIED_DATE,
+                    NoteColumns.TYPE,
+                    NoteColumns.PINNED,
+                    NoteColumns.LOCKED,
+                    NoteColumns.PUBLIC
+            };
+
+            String selection = NoteColumns.USER_ID + " = ? AND " + NoteColumns.PUBLIC + " = 1 AND " + NoteColumns.PARENT_ID + " <> " + Notes.ID_TRASH_FOLER;
+            String[] selectionArgs = {String.valueOf(mFriendId)};
+
+            Cursor cursor = null;
+            try {
+                cursor = getContentResolver().query(
+                        Notes.CONTENT_NOTE_URI,
+                        projection,
+                        selection,
+                        selectionArgs,
+                        NoteColumns.PINNED + " DESC, " + NoteColumns.MODIFIED_DATE + " DESC"
+                );
+
+                if (cursor != null) {
+                    while (cursor.moveToNext()) {
+                        long id = cursor.getLong(cursor.getColumnIndexOrThrow(NoteColumns.ID));
+                        String title = cursor.getString(cursor.getColumnIndexOrThrow(NoteColumns.TITLE));
+                        String content = cursor.getString(cursor.getColumnIndexOrThrow(NoteColumns.SNIPPET));
+                        long modifiedDate = cursor.getLong(cursor.getColumnIndexOrThrow(NoteColumns.MODIFIED_DATE));
+                        int type = cursor.getInt(cursor.getColumnIndexOrThrow(NoteColumns.TYPE));
+                        int pinned = cursor.getInt(cursor.getColumnIndexOrThrow(NoteColumns.PINNED));
+                        int locked = cursor.getInt(cursor.getColumnIndexOrThrow(NoteColumns.LOCKED));
+                        int isPublic = cursor.getInt(cursor.getColumnIndexOrThrow(NoteColumns.PUBLIC));
+
+                        mNoteList.add(new Note(id, title, content, modifiedDate, type, pinned, locked, isPublic));
+                    }
+                }
+            } catch (Exception e) {
+                e.printStackTrace();
+                Toast.makeText(this, "查询好友便签失败: " + e.getMessage(), Toast.LENGTH_SHORT).show();
+            } finally {
+                if (cursor != null) {
+                    cursor.close();
+                }
+            }
+
+            // 通知适配器数据变化
+            mNoteAdapter.notifyDataSetChanged();
+
+            // 如果没有公开便签，显示提示
+            if (mNoteList.isEmpty()) {
+                Toast.makeText(this, mFriendUsername + "没有公开的便签", Toast.LENGTH_SHORT).show();
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+            Toast.makeText(this, "加载好友便签失败", Toast.LENGTH_SHORT).show();
+        }
+    }
+
+    /**
+     * 便签实体类
+     */
+    private static class Note {
+        long id;
+        String title;
+        String content;
+        long modifiedDate;
+        int type;
+        int pinned;
+        int locked;
+        int isPublic;
+
+        Note(long id, String title, String content, long modifiedDate, int type, int pinned, int locked, int isPublic) {
+            this.id = id;
+            this.title = title;
+            this.content = content;
+            this.modifiedDate = modifiedDate;
+            this.type = type;
+            this.pinned = pinned;
+            this.locked = locked;
+            this.isPublic = isPublic;
+        }
+    }
+
+    /**
+     * 便签列表适配器
+     */
+    private static class NoteAdapter extends BaseAdapter {
+        private Activity mActivity;
+        private List<Note> mNoteList;
+        private LayoutInflater mInflater;
+
+        NoteAdapter(Activity activity, List<Note> noteList) {
+            mActivity = activity;
+            mNoteList = noteList;
+            mInflater = LayoutInflater.from(activity);
+        }
+
+        @Override
+        public int getCount() {
+            return mNoteList.size();
+        }
+
+        @Override
+        public Object getItem(int position) {
+            return mNoteList.get(position);
+        }
+
+        @Override
+        public long getItemId(int position) {
+            return position;
+        }
+
+        @Override
+        public View getView(int position, View convertView, ViewGroup parent) {
+            ViewHolder holder;
+            if (convertView == null) {
+                convertView = mInflater.inflate(R.layout.note_item, parent, false);
+                holder = new ViewHolder();
+                holder.titleTextView = convertView.findViewById(R.id.tv_title);
+            holder.modifiedDateTextView = convertView.findViewById(R.id.tv_time);
+            holder.pinnedImageView = convertView.findViewById(R.id.iv_alert_icon);
+            holder.lockedImageView = convertView.findViewById(R.id.iv_lock_icon);
+            holder.publicImageView = convertView.findViewById(R.id.iv_public_icon);
+                convertView.setTag(holder);
+            } else {
+                holder = (ViewHolder) convertView.getTag();
+            }
+
+            Note note = mNoteList.get(position);
+            // 显示标题，如果标题为空则显示内容摘要
+            String displayText;
+            if (note.title != null && !note.title.isEmpty()) {
+                displayText = note.title;
+            } else {
+                displayText = note.content;
+            }
+            holder.titleTextView.setText(displayText);
+            holder.modifiedDateTextView.setText(android.text.format.DateUtils.formatDateTime(
+                    mActivity, note.modifiedDate, 
+                    android.text.format.DateUtils.FORMAT_SHOW_DATE | 
+                            android.text.format.DateUtils.FORMAT_NUMERIC_DATE | 
+                            android.text.format.DateUtils.FORMAT_SHOW_TIME));
+
+            // 设置置顶图标
+            holder.pinnedImageView.setVisibility(note.pinned == 1 ? View.VISIBLE : View.GONE);
+
+            // 设置锁定图标
+            holder.lockedImageView.setVisibility(note.locked == 1 ? View.VISIBLE : View.GONE);
+
+            // 设置公开图标
+            holder.publicImageView.setVisibility(note.isPublic == 1 ? View.VISIBLE : View.GONE);
+
+            return convertView;
+        }
+
+        private static class ViewHolder {
+            TextView titleTextView;
+            TextView modifiedDateTextView;
+            ImageView pinnedImageView;
+            ImageView lockedImageView;
+            ImageView publicImageView;
+        }
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(android.view.MenuItem item) {
+        switch (item.getItemId()) {
+            case android.R.id.home:
+                // 返回上一级活动
+                finish();
+                return true;
+            default:
+                return super.onOptionsItemSelected(item);
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Notes-master/src/net/micode/notes/ui/LoginActivity.java b/src/Notes-master/src/net/micode/notes/ui/LoginActivity.java
new file mode 100644
index 0000000..d613e4a
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/ui/LoginActivity.java
@@ -0,0 +1,321 @@
+/*
+ * 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.content.ContentValues;
+import android.content.Intent;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.os.Bundle;
+import android.view.View;
+import android.widget.Button;
+import android.widget.EditText;
+import android.widget.Toast;
+
+import androidx.appcompat.app.AlertDialog;
+import androidx.appcompat.app.AppCompatActivity;
+
+import net.micode.notes.R;
+import net.micode.notes.data.NotesDatabaseHelper;
+import net.micode.notes.data.Users;
+import net.micode.notes.tool.UserManager;
+
+public class LoginActivity extends AppCompatActivity {
+
+    private EditText etUsername;
+    private EditText etPassword;
+
+    private NotesDatabaseHelper mDbHelper;
+    private SQLiteDatabase mDb;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_login);
+
+        // 初始化数据库
+        mDbHelper = NotesDatabaseHelper.getInstance(this);
+        mDb = mDbHelper.getWritableDatabase();
+
+        // 初始化控件
+        etUsername = findViewById(R.id.et_username);
+        etPassword = findViewById(R.id.et_password);
+    }
+
+    /**
+     * 登录按钮点击事件
+     */
+    public void onLoginClick(View view) {
+        String username = etUsername.getText().toString().trim();
+        String password = etPassword.getText().toString().trim();
+
+        // 验证输入
+        if (username.isEmpty() || password.isEmpty()) {
+            Toast.makeText(this, "用户名和密码不能为空", Toast.LENGTH_SHORT).show();
+            return;
+        }
+
+        // 验证用户名和密码
+        long userId = validateUser(username, password);
+        if (userId != -1) {
+            // 登录成功，保存用户信息
+            UserManager userManager = UserManager.getInstance(this);
+            userManager.saveCurrentUser(userId, username);
+            
+            // 跳转到便签列表
+            Intent intent = new Intent(this, NotesListActivity.class);
+            startActivity(intent);
+            finish();
+        } else {
+            // 登录失败，提示错误
+            Toast.makeText(this, "用户名或密码错误", Toast.LENGTH_SHORT).show();
+        }
+    }
+
+    /**
+     * 注册按钮点击事件
+     */
+    public void onRegisterClick(View view) {
+        showRegisterDialog();
+    }
+
+    /**
+     * 修改密码按钮点击事件
+     */
+    public void onChangePasswordClick(View view) {
+        showChangePasswordDialog();
+    }
+
+    /**
+     * 显示注册对话框
+     */
+    private void showRegisterDialog() {
+        View dialogView = getLayoutInflater().inflate(R.layout.dialog_register, null);
+        AlertDialog.Builder builder = new AlertDialog.Builder(this);
+        builder.setView(dialogView);
+
+        final AlertDialog dialog = builder.create();
+
+        // 初始化注册对话框控件
+        final EditText etRegisterUsername = dialogView.findViewById(R.id.et_register_username);
+        final EditText etRegisterPassword = dialogView.findViewById(R.id.et_register_password);
+        final EditText etRegisterConfirmPassword = dialogView.findViewById(R.id.et_register_confirm_password);
+        Button btnRegisterCancel = dialogView.findViewById(R.id.btn_register_cancel);
+        Button btnRegisterConfirm = dialogView.findViewById(R.id.btn_register_confirm);
+
+        // 取消按钮点击事件
+        btnRegisterCancel.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                dialog.dismiss();
+            }
+        });
+
+        // 注册按钮点击事件
+        btnRegisterConfirm.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                String username = etRegisterUsername.getText().toString().trim();
+                String password = etRegisterPassword.getText().toString().trim();
+                String confirmPassword = etRegisterConfirmPassword.getText().toString().trim();
+
+                // 验证输入
+                if (username.isEmpty() || password.isEmpty() || confirmPassword.isEmpty()) {
+                    Toast.makeText(LoginActivity.this, "请填写完整信息", Toast.LENGTH_SHORT).show();
+                    return;
+                }
+
+                if (!password.equals(confirmPassword)) {
+                    Toast.makeText(LoginActivity.this, "两次输入的密码不一致", Toast.LENGTH_SHORT).show();
+                    return;
+                }
+
+                // 检查用户名是否已存在
+                if (isUsernameExists(username)) {
+                    Toast.makeText(LoginActivity.this, "用户名已存在", Toast.LENGTH_SHORT).show();
+                    return;
+                }
+
+                // 注册用户
+                if (registerUser(username, password)) {
+                    Toast.makeText(LoginActivity.this, "注册成功", Toast.LENGTH_SHORT).show();
+                    dialog.dismiss();
+                } else {
+                    Toast.makeText(LoginActivity.this, "注册失败，请重试", Toast.LENGTH_SHORT).show();
+                }
+            }
+        });
+
+        dialog.show();
+    }
+
+    /**
+     * 显示修改密码对话框
+     */
+    private void showChangePasswordDialog() {
+        View dialogView = getLayoutInflater().inflate(R.layout.dialog_change_password, null);
+        AlertDialog.Builder builder = new AlertDialog.Builder(this);
+        builder.setView(dialogView);
+
+        final AlertDialog dialog = builder.create();
+
+        // 初始化修改密码对话框控件
+        final EditText etChangeUsername = dialogView.findViewById(R.id.et_change_username);
+        final EditText etCurrentPassword = dialogView.findViewById(R.id.et_current_password);
+        final EditText etNewPassword = dialogView.findViewById(R.id.et_new_password);
+        final EditText etConfirmNewPassword = dialogView.findViewById(R.id.et_confirm_new_password);
+        Button btnChangeCancel = dialogView.findViewById(R.id.btn_change_cancel);
+        Button btnChangeConfirm = dialogView.findViewById(R.id.btn_change_confirm);
+
+        // 取消按钮点击事件
+        btnChangeCancel.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                dialog.dismiss();
+            }
+        });
+
+        // 确认修改按钮点击事件
+        btnChangeConfirm.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                String username = etChangeUsername.getText().toString().trim();
+                String currentPassword = etCurrentPassword.getText().toString().trim();
+                String newPassword = etNewPassword.getText().toString().trim();
+                String confirmNewPassword = etConfirmNewPassword.getText().toString().trim();
+
+                // 验证输入
+                if (username.isEmpty() || currentPassword.isEmpty() || newPassword.isEmpty() || confirmNewPassword.isEmpty()) {
+                    Toast.makeText(LoginActivity.this, "请填写完整信息", Toast.LENGTH_SHORT).show();
+                    return;
+                }
+
+                if (!newPassword.equals(confirmNewPassword)) {
+                    Toast.makeText(LoginActivity.this, "两次输入的新密码不一致", Toast.LENGTH_SHORT).show();
+                    return;
+                }
+
+                // 验证当前密码
+                if (validateUser(username, currentPassword) == -1) {
+                    Toast.makeText(LoginActivity.this, "用户名或当前密码错误", Toast.LENGTH_SHORT).show();
+                    return;
+                }
+
+                // 修改密码
+                if (changePassword(username, newPassword)) {
+                    Toast.makeText(LoginActivity.this, "密码修改成功", Toast.LENGTH_SHORT).show();
+                    dialog.dismiss();
+                } else {
+                    Toast.makeText(LoginActivity.this, "密码修改失败，请重试", Toast.LENGTH_SHORT).show();
+                }
+            }
+        });
+
+        dialog.show();
+    }
+
+    /**
+     * 验证用户名和密码，并返回用户ID
+     */
+    private long validateUser(String username, String password) {
+        String[] projection = {Users.UserColumns.ID};
+        String selection = Users.UserColumns.USERNAME + " = ? AND " + Users.UserColumns.PASSWORD + " = ?";
+        String[] selectionArgs = {username, password};
+
+        Cursor cursor = mDb.query(
+                NotesDatabaseHelper.TABLE.USER,
+                projection,
+                selection,
+                selectionArgs,
+                null,
+                null,
+                null
+        );
+
+        long userId = -1;
+        if (cursor.moveToFirst()) {
+            userId = cursor.getLong(cursor.getColumnIndexOrThrow(Users.UserColumns.ID));
+        }
+        cursor.close();
+        return userId;
+    }
+
+    /**
+     * 检查用户名是否已存在
+     */
+    private boolean isUsernameExists(String username) {
+        String[] projection = {Users.UserColumns.ID};
+        String selection = Users.UserColumns.USERNAME + " = ?";
+        String[] selectionArgs = {username};
+
+        Cursor cursor = mDb.query(
+                NotesDatabaseHelper.TABLE.USER,
+                projection,
+                selection,
+                selectionArgs,
+                null,
+                null,
+                null
+        );
+
+        boolean exists = cursor.getCount() > 0;
+        cursor.close();
+        return exists;
+    }
+
+    /**
+     * 注册用户
+     */
+    private boolean registerUser(String username, String password) {
+        ContentValues values = new ContentValues();
+        values.put(Users.UserColumns.USERNAME, username);
+        values.put(Users.UserColumns.PASSWORD, password);
+
+        long result = mDb.insert(NotesDatabaseHelper.TABLE.USER, null, values);
+        return result != -1;
+    }
+
+    /**
+     * 修改密码
+     */
+    private boolean changePassword(String username, String newPassword) {
+        ContentValues values = new ContentValues();
+        values.put(Users.UserColumns.PASSWORD, newPassword);
+        values.put(Users.UserColumns.MODIFIED_DATE, System.currentTimeMillis());
+
+        String selection = Users.UserColumns.USERNAME + " = ?";
+        String[] selectionArgs = {username};
+
+        int result = mDb.update(
+                NotesDatabaseHelper.TABLE.USER,
+                values,
+                selection,
+                selectionArgs
+        );
+
+        return result > 0;
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        // 关闭数据库连接
+        if (mDb != null && mDb.isOpen()) {
+            mDb.close();
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Notes-master/src/net/micode/notes/ui/SplashActivity.java b/src/Notes-master/src/net/micode/notes/ui/SplashActivity.java
new file mode 100644
index 0000000..f3d7a3f
--- /dev/null
+++ b/src/Notes-master/src/net/micode/notes/ui/SplashActivity.java
@@ -0,0 +1,56 @@
+package net.micode.notes.ui;
+
+import android.app.Activity;
+import android.content.Intent;
+import android.os.Bundle;
+import android.os.Handler;
+import android.view.animation.AlphaAnimation;
+import android.view.animation.Animation;
+import android.widget.LinearLayout;
+
+import net.micode.notes.R;
+
+public class SplashActivity extends Activity {
+
+    private static final int SPLASH_DISPLAY_DURATION = 2000; // 2秒
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_splash);
+
+        // 找到小米logo容器
+        LinearLayout miLogo = findViewById(R.id.mi_logo);
+
+        // 创建淡入淡出动画
+        AlphaAnimation animation = new AlphaAnimation(0.0f, 1.0f);
+        animation.setDuration(1500); // 1.5秒
+        animation.setAnimationListener(new Animation.AnimationListener() {
+            @Override
+            public void onAnimationStart(Animation animation) {
+                // 动画开始时的回调
+            }
+
+            @Override
+            public void onAnimationEnd(Animation animation) {
+                // 动画结束后跳转到主界面
+                new Handler().postDelayed(new Runnable() {
+                    @Override
+                    public void run() {
+                        Intent mainIntent = new Intent(SplashActivity.this, NotesListActivity.class);
+                        SplashActivity.this.startActivity(mainIntent);
+                        SplashActivity.this.finish();
+                    }
+                }, 500); // 延迟500毫秒后跳转
+            }
+
+            @Override
+            public void onAnimationRepeat(Animation animation) {
+                // 动画重复时的回调
+            }
+        });
+
+        // 应用动画到小米logo
+        miLogo.startAnimation(animation);
+    }
+}
\ No newline at end of file