diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 0ab3320..c6f0d7a 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -11,24 +11,24 @@
         android:supportsRtl="true"
         android:theme="@style/Theme.MyApplication"
         tools:targetApi="31">
-
         <activity
             android:name=".UserInfoActivity"
+            android:exported="false" />
+        <activity
+            android:name=".MainActivity"
             android:exported="true">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
+
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
-
         <activity
             android:name=".RegisterActivity"
             android:exported="false" />
-
         <activity
             android:name=".LoginActivity"
             android:exported="false" />
-
     </application>
 
 </manifest>
\ No newline at end of file
diff --git a/app/src/main/java/cc/liuyx/app/MainActivity.java b/app/src/main/java/cc/liuyx/app/MainActivity.java
new file mode 100644
index 0000000..84fbb13
--- /dev/null
+++ b/app/src/main/java/cc/liuyx/app/MainActivity.java
@@ -0,0 +1,45 @@
+package cc.liuyx.app;
+
+import android.annotation.SuppressLint;
+import android.content.SharedPreferences;
+import android.os.Bundle;
+import android.util.Log;
+import android.view.View;
+
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.fragment.app.FragmentManager;
+import androidx.fragment.app.FragmentTransaction;
+
+import cc.liuyx.app.fragment.MainFragment;
+import cc.liuyx.app.fragment.InfoFragment;
+
+public class MainActivity extends AppCompatActivity {
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_main);
+
+        SharedPreferences preferences = getSharedPreferences("loginStatus", MODE_PRIVATE);
+        Log.i("log", preferences.getString("username", "no name"));
+    }
+
+    @SuppressLint("NonConstantResourceId")
+    public void selectFragment(View view) {
+        FragmentManager fm = getSupportFragmentManager();
+        FragmentTransaction ft = fm.beginTransaction();
+
+        MainFragment firstFragment = new MainFragment();
+        InfoFragment infoFragment = new InfoFragment();
+
+        switch (view.getId()) {
+            case R.id.page_main:
+                ft.replace(R.id.page_blank, firstFragment);
+                break;
+            case R.id.page_info:
+                ft.replace(R.id.page_blank, infoFragment);
+                break;
+        }
+        ft.commit();
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/cc/liuyx/app/RegisterActivity.java b/app/src/main/java/cc/liuyx/app/RegisterActivity.java
index 715f9ba..ad0f5d4 100644
--- a/app/src/main/java/cc/liuyx/app/RegisterActivity.java
+++ b/app/src/main/java/cc/liuyx/app/RegisterActivity.java
@@ -53,7 +53,7 @@ public class RegisterActivity extends AppCompatActivity implements View.OnClickL
     }
 
     private void validateRegister() {
-        Intent intent = new Intent(RegisterActivity.this, UserInfoActivity.class);
+        Intent intent = new Intent(RegisterActivity.this, MainActivity.class);
 
         username = usernameEdit.getText().toString();
         passwd = passwdEdit.getText().toString();
diff --git a/app/src/main/java/cc/liuyx/app/fragment/InfoFragment.java b/app/src/main/java/cc/liuyx/app/fragment/InfoFragment.java
new file mode 100644
index 0000000..38631bd
--- /dev/null
+++ b/app/src/main/java/cc/liuyx/app/fragment/InfoFragment.java
@@ -0,0 +1,19 @@
+package cc.liuyx.app.fragment;
+
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import androidx.fragment.app.Fragment;
+
+import cc.liuyx.app.R;
+
+public class InfoFragment extends Fragment {
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
+        return inflater.inflate(R.layout.fragment_info, container, false);
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/cc/liuyx/app/fragment/MainFragment.java b/app/src/main/java/cc/liuyx/app/fragment/MainFragment.java
new file mode 100644
index 0000000..489aee9
--- /dev/null
+++ b/app/src/main/java/cc/liuyx/app/fragment/MainFragment.java
@@ -0,0 +1,19 @@
+package cc.liuyx.app.fragment;
+
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import androidx.fragment.app.Fragment;
+
+import cc.liuyx.app.R;
+
+public class MainFragment extends Fragment {
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
+        return inflater.inflate(R.layout.fragment_main, container, false);
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
new file mode 100644
index 0000000..6737081
--- /dev/null
+++ b/app/src/main/res/layout/activity_main.xml
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout 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:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical"
+    tools:context=".MainActivity">
+
+    <LinearLayout
+        android:id="@+id/page_blank"
+        android:layout_width="wrap_content"
+        android:layout_height="0dp"
+        android:layout_weight="19" />
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_weight="1">
+
+        <TextView
+            android:textAlignment="center"
+            android:id="@+id/page_main"
+            android:layout_width="0dp"
+            android:layout_height="match_parent"
+            android:text="主页"
+            android:layout_weight="1"
+            android:textSize="@dimen/normal_font_size"
+            android:onClick="selectFragment" />
+
+        <TextView
+            android:textAlignment="center"
+            android:id="@+id/page_info"
+            android:layout_width="0dp"
+            android:layout_height="match_parent"
+            android:text="我的"
+            android:layout_weight="1"
+            android:textSize="@dimen/normal_font_size"
+            android:onClick="selectFragment" />
+
+    </LinearLayout>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/fragment_info.xml b/app/src/main/res/layout/fragment_info.xml
new file mode 100644
index 0000000..35f158b
--- /dev/null
+++ b/app/src/main/res/layout/fragment_info.xml
@@ -0,0 +1,207 @@
+<?xml version="1.0" encoding="utf-8"?>
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".fragment.InfoFragment">
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical"
+        tools:ignore="UselessParent">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="45dp"
+            android:layout_marginBottom="30dp"
+            android:gravity="center">
+
+            <ImageView
+                android:layout_width="80dp"
+                android:layout_height="80dp"
+                android:src="@drawable/ic_avatar" />
+        </LinearLayout>
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:background="@drawable/shape_infoitem"
+            android:gravity="center">
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:src="@drawable/ic_user" />
+
+            <TextView
+                android:id="@+id/user_username"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="8"
+                android:text="  用户名："
+                android:textSize="@dimen/normal_font_size" />
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_gravity="end"
+                android:layout_weight="1"
+                android:src="@drawable/ic_arrow_right" />
+
+        </LinearLayout>
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:background="@drawable/shape_infoitem"
+            android:gravity="center">
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:src="@drawable/ic_phone" />
+
+            <TextView
+                android:id="@+id/user_phone"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="8"
+                android:text="  手机号："
+                android:textSize="@dimen/normal_font_size" />
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_gravity="end"
+                android:layout_weight="1"
+                android:src="@drawable/ic_arrow_right" />
+
+        </LinearLayout>
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginBottom="15dp"
+            android:background="@drawable/shape_infoitem"
+            android:gravity="center">
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:src="@drawable/ic_email" />
+
+            <TextView
+                android:id="@+id/user_email"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="8"
+                android:text="  邮箱："
+                android:textSize="@dimen/normal_font_size" />
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_gravity="end"
+                android:layout_weight="1"
+                android:src="@drawable/ic_arrow_right" />
+
+        </LinearLayout>
+
+        <LinearLayout
+            android:id="@+id/user_setting"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginBottom="15dp"
+            android:background="@drawable/shape_infoitem"
+            android:gravity="center">
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:src="@drawable/ic_setting" />
+
+            <TextView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="8"
+                android:text="  设置"
+                android:textSize="@dimen/normal_font_size" />
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_gravity="end"
+                android:layout_weight="1"
+                android:src="@drawable/ic_arrow_right" />
+
+        </LinearLayout>
+
+        <LinearLayout
+            android:id="@+id/more"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:background="@drawable/shape_infoitem"
+            android:gravity="center">
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:src="@drawable/ic_more" />
+
+            <TextView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="8"
+                android:text="  更多"
+                android:textSize="@dimen/normal_font_size" />
+
+            <ImageView
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_gravity="end"
+                android:layout_weight="1"
+                android:src="@drawable/ic_arrow_right" />
+
+        </LinearLayout>
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="20dp"
+            android:gravity="center">
+
+
+        </LinearLayout>
+
+        <RelativeLayout
+            android:layout_width="match_parent"
+            android:layout_height="match_parent">
+
+            <Button
+                android:id="@+id/logout"
+                android:layout_width="200dp"
+                android:layout_height="wrap_content"
+                android:layout_above="@+id/footnote"
+                android:layout_centerHorizontal="true"
+                android:layout_marginBottom="30dp"
+                android:text="退出登录" />
+
+            <TextView
+                android:id="@+id/footnote"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_alignParentBottom="true"
+                android:layout_marginBottom="10dp"
+                android:text="@string/footnote"
+                android:textAlignment="center" />
+        </RelativeLayout>
+    </LinearLayout>
+
+</FrameLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/fragment_main.xml b/app/src/main/res/layout/fragment_main.xml
new file mode 100644
index 0000000..b3628ca
--- /dev/null
+++ b/app/src/main/res/layout/fragment_main.xml
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".fragment.MainFragment">
+
+    <TextView
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:text="这是主页！" />
+
+</FrameLayout>
\ No newline at end of file
diff --git a/app/src/main/res/navigation/nav_graph.xml b/app/src/main/res/navigation/nav_graph.xml
index fc92c81..d393cf5 100644
--- a/app/src/main/res/navigation/nav_graph.xml
+++ b/app/src/main/res/navigation/nav_graph.xml
@@ -9,7 +9,7 @@
         android:id="@+id/FirstFragment"
         android:name="com.example.myapplication.FirstFragment"
         android:label="@string/first_fragment_label"
-        tools:layout="@layout/fragment_first">
+        tools:layout="@layout/fragment_main">
 
         <action
             android:id="@+id/action_FirstFragment_to_SecondFragment"
diff --git a/app/src/main/res/navigation/nav_graph2.xml b/app/src/main/res/navigation/nav_graph2.xml
index 9118892..4740064 100644
--- a/app/src/main/res/navigation/nav_graph2.xml
+++ b/app/src/main/res/navigation/nav_graph2.xml
@@ -9,7 +9,7 @@
         android:id="@+id/FirstFragment"
         android:name="com.example.myapplication.FirstFragment"
         android:label="@string/first_fragment_label"
-        tools:layout="@layout/fragment_first" >
+        tools:layout="@layout/fragment_main">
 
         <action
             android:id="@+id/action_FirstFragment_to_SecondFragment"
@@ -19,7 +19,7 @@
         android:id="@+id/SecondFragment"
         android:name="com.example.myapplication.SecondFragment"
         android:label="@string/second_fragment_label"
-        tools:layout="@layout/fragment_second" >
+        tools:layout="@layout/fragment_second">
 
         <action
             android:id="@+id/action_SecondFragment_to_FirstFragment"
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index ead7e7f..10b8207 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -12,4 +12,6 @@
     <string name="title_activity_register">RegisterActivity</string>
 
     <string name="footnote">联系我：liuyxcc@gmail.com</string>
+    <!-- TODO: Remove or change this placeholder text -->
+    <string name="hello_blank_fragment">Hello blank fragment</string>
 </resources>
\ No newline at end of file