feat: 上传第三次安卓课程代码(2026年10月09日)

app/src/main/AndroidManifest.xml

@@ -10,15 +10,20 @@
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/Theme.ActivityTest6117_1">
-
         <activity
             android:name=".FirstActivity"
             android:exported="true">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
+                <action android:name="com.yanzitong.activitytest6117.action.YZT_FIRST" />
+
                 <category android:name="android.intent.category.LAUNCHER" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="com.yanzitong.activitytest6117.category.YZT_FIRST" />
             </intent-filter>
         </activity>
+        <activity android:name=".SecondActivity" />
+        <activity android:name=".ThirdActivity" />
     </application>
 
 </manifest>

app/src/main/java/com/yanzitong/activitytest6117/FirstActivity.java

@@ -1,16 +1,20 @@
 package com.yanzitong.activitytest6117;
 
+import android.content.Intent;
 import android.os.Bundle;
 import android.util.Log;
+import android.view.ContextMenu;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
 import android.widget.Button;
+import android.widget.LinearLayout;
 import android.widget.Toast;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.AppCompatActivity;
+import androidx.appcompat.widget.PopupMenu;
 
 // 组合键：shift + enter
 public class FirstActivity extends AppCompatActivity {
@@ -20,6 +24,9 @@ public class FirstActivity extends AppCompatActivity {
     // 全局（成员）变量：m开头
     Button mFirstBtn1;
     Button mFirstBtn2;
+    LinearLayout mFirstLinearLayout;
+    Button mFirstBtn3;
+    Button mFirstBtn4;
 
     /**
      * 事件驱动机制
@@ -33,13 +40,40 @@ public class FirstActivity extends AppCompatActivity {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.first_layout);
         Log.d(TAG, "onCreate: 活动创建成功"); // 组合键2：alter + enter
+
+        mFirstBtn4 = findViewById(R.id.first_btn4);
+        mFirstBtn4.setOnClickListener(v -> {
+            // Activity之间的跳转——显式Intent
+            Intent intent = new Intent(FirstActivity.this, SecondActivity.class);
+            startActivity(intent);
+        });
+
+        mFirstBtn3 = findViewById(R.id.first_btn3);
+        mFirstBtn3.setOnClickListener(v -> {
+            finish();
+        });
+
         mFirstBtn1 = findViewById(R.id.first_btn1);
         mFirstBtn1.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
                 Toast.makeText(FirstActivity.this, "6117严梓桐单击了按钮", Toast.LENGTH_SHORT).show();
+                PopupMenu popupMenu = new PopupMenu(FirstActivity.this, v);     // this, super
+                popupMenu.getMenuInflater().inflate(R.menu.main, popupMenu.getMenu());
+                popupMenu.setOnMenuItemClickListener(item -> {
+                    if (item.getItemId() == R.id.add_item) {
+                        Toast.makeText(FirstActivity.this, "单击了add按钮", Toast.LENGTH_SHORT).show();
+                    } else if (item.getItemId() == R.id.modify_item) {
+                        Toast.makeText(FirstActivity.this, "单击了modify按钮", Toast.LENGTH_SHORT).show();
+                    } else if (item.getItemId() == R.id.delete_item) {
+                        Toast.makeText(FirstActivity.this, "单击了delete按钮", Toast.LENGTH_SHORT).show();
+                    }
+                    return true;
+                });     // 箭头函数（lambda表达式）——接口[只能有一个抽象函数]
+                popupMenu.show();
             }
         });
+
         mFirstBtn2 = findViewById(R.id.first_btn2);
         mFirstBtn2.setOnClickListener(new View.OnClickListener() {
             @Override
@@ -48,8 +82,43 @@ public class FirstActivity extends AppCompatActivity {
                 Toast.makeText(FirstActivity.this, "我是严梓桐", Toast.LENGTH_SHORT).show();
             }
         });
+
+        mFirstLinearLayout = findViewById(R.id.first_linear_layout);
+        registerForContextMenu(mFirstLinearLayout);
     }
 
+    // 弹出式菜单——触发事件
+
+
+    // 上下文菜单
+    // ctrl + shift + "+ / -": 展开、折叠代码块
+    @Override
+    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
+        super.onCreateContextMenu(menu, v, menuInfo);
+        menu.setHeaderTitle("上下文菜单");
+        // 参数1：分组号，参数2：item编号，参数3：顺序编号
+        menu.add(1, 1, 1, "保存");
+        menu.add(1, 2, 2, "更改");
+        menu.add(1, 3, 3, "删除");
+    }
+
+    @Override
+    public boolean onContextItemSelected(@NonNull MenuItem item) {
+        if (item.getItemId() == 1) {
+            Toast.makeText(this, "人物简介——特长", Toast.LENGTH_SHORT).show();
+            Log.d(TAG, "onContextItemSelected: 人物简介——特长");
+        } else if (item.getItemId() == 2) {
+            Toast.makeText(this, "人物简介——战斗力", Toast.LENGTH_SHORT).show();
+            Log.d(TAG, "onContextItemSelected: 人物简介——战斗力");
+        } else if (item.getItemId() == 3) {
+            Toast.makeText(this, "人物简介——经典语录", Toast.LENGTH_SHORT).show();
+            Log.d(TAG, "onContextItemSelected: 人物简介——经典语录");
+        }
+
+        return super.onContextItemSelected(item);
+    }
+
+    // 选项菜单
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.main, menu);
@@ -74,6 +143,7 @@ public class FirstActivity extends AppCompatActivity {
 
 /**
  * 添加一个按钮，id = first_btn2，完成单击事件：弹出Toast消息日志，内容自定义，带个人标识
+ * <p>
  * mFirstBtn2 = findViewById(R.id.first_btn2);
  * mFirstBtn2.setOnClickListener(new View.OnClickListener() {
  *

app/src/main/java/com/yanzitong/activitytest6117/SecondActivity.java

@@ -0,0 +1,27 @@
+package com.yanzitong.activitytest6117;
+
+import android.content.Intent;
+import android.os.Bundle;
+import android.widget.Button;
+
+import androidx.annotation.Nullable;
+import androidx.appcompat.app.AppCompatActivity;
+
+public class SecondActivity extends AppCompatActivity {
+    @Override
+    protected void onCreate(@Nullable Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.second_layout);
+        Button mSecondBtn1 = findViewById(R.id.second_btn1);
+        mSecondBtn1.setOnClickListener(v -> {
+            Intent intent = new Intent(SecondActivity.this, ThirdActivity.class);
+            startActivity(intent);
+        });
+    }
+}
+/**
+ * your turn:
+ * 新建UI: third_layout和Java class: thirdActivity
+ * 按钮text = "跳转到ThirdActivity"
+ * 完成单击事件：实现从 SecondActivity 显式跳转到 ThirdActivity
+ */

app/src/main/java/com/yanzitong/activitytest6117/ThirdActivity.java

@@ -0,0 +1,46 @@
+package com.yanzitong.activitytest6117;
+
+import android.content.Intent;
+import android.os.Bundle;
+import android.widget.Button;
+
+import androidx.appcompat.app.AppCompatActivity;
+
+public class ThirdActivity extends AppCompatActivity {
+
+    private Button mThirdBtn1;
+    private Button mThirdBtn2;
+    private Button mThirdBtn3;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.third_layout);
+
+        mThirdBtn1 = findViewById(R.id.third_btn1);
+        mThirdBtn1.setOnClickListener(v -> {    // 项目内部隐式Intent：匹配action和category
+            Intent intent = new Intent("com.yanzitong.activitytest6117.action.YZT_FIRST");  // 为FirstActivity定义对应的action
+            intent.addCategory("com.yanzitong.activitytest6117.category.YZT_FIRST");
+            startActivity(intent);
+        });
+
+        mThirdBtn2 = findViewById(R.id.third_btn2);
+        mThirdBtn3 = findViewById(R.id.third_btn3);
+        mThirdBtn2.setOnClickListener(v -> {
+            Intent intent = new Intent(Intent.ACTION_VIEW);     // 等价于"Intent intent = new Intent(android.intent.action.VIEW)"
+            startActivity(intent);
+        });
+        mThirdBtn3.setOnClickListener(v -> {
+            Intent intent = new Intent();
+            startActivity(intent);
+        });
+    }
+
+    // 隐式Intent——项目内部或项目之间的调用
+    // 1. 实现ThirdActivity返回FirstActivity
+    /**
+     * 为FirstActivity定义对应的action和category的值
+     * category可以是默认值，不可缺
+     * category自定义
+     */
+}

app/src/main/res/layout/first_layout.xml

@@ -1,22 +1,37 @@
 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/first_linear_layout"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical">
 
+    <Button
+        android:id="@+id/first_btn4"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="跳转到SecondActivity"
+        android:textAllCaps="false" />
+
     <Button
         android:id="@+id/first_btn1"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:textAllCaps="false"
         android:layout_marginTop="50dp"
-        android:text="显示Toast消息" />
+        android:text="显示Toast消息"
+        android:textAllCaps="false" />
 
     <Button
         android:id="@+id/first_btn2"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:textAllCaps="false"
         android:layout_marginTop="50dp"
-        android:text="我是严梓桐" />
+        android:text="我是严梓桐"
+        android:textAllCaps="false" />
+
+    <Button
+        android:id="@+id/first_btn3"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="退出当前Activity"
+        android:textAllCaps="false" />
 </LinearLayout>

app/src/main/res/layout/second_layout.xml

@@ -0,0 +1,22 @@
+<?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:layout_margin="15dp"
+    android:orientation="vertical">
+
+    <TextView
+        android:id="@+id/second_show_msg_tv"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:hint="显示数据"
+        android:textColor="#F00"
+        android:textSize="18sp" />
+
+    <Button
+        android:id="@+id/second_btn1"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="跳转到ThirdActivity"
+        android:textAllCaps="false" />
+</LinearLayout>

app/src/main/res/layout/third_layout.xml

@@ -0,0 +1,30 @@
+<?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">
+
+    <Button
+        android:id="@+id/third_btn1"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="50dp"
+        android:text="隐式跳转到FirstActivity"
+        android:textAllCaps="false" />
+
+    <Button
+        android:id="@+id/third_btn2"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="50dp"
+        android:text="打开浏览器"
+        android:textAllCaps="false" />
+
+    <Button
+        android:id="@+id/third_btn3"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="50dp"
+        android:text="打开拨号界面"
+        android:textAllCaps="false" />
+</LinearLayout>

app/src/main/res/values-night/themes.xml

@@ -13,4 +13,18 @@
         <item name="android:statusBarColor">?attr/colorPrimaryVariant</item>
         <!-- Customize your theme here. -->
     </style>
+
+    <style name="Theme.ActivityTest6117_1" parent="Theme.MaterialComponents.DayNight.NoActionBar">
+        <!-- Primary brand color. -->
+        <item name="colorPrimary">@color/purple_200</item>
+        <item name="colorPrimaryVariant">@color/purple_700</item>
+        <item name="colorOnPrimary">@color/black</item>
+        <!-- Secondary brand color. -->
+        <item name="colorSecondary">@color/teal_200</item>
+        <item name="colorSecondaryVariant">@color/teal_200</item>
+        <item name="colorOnSecondary">@color/black</item>
+        <!-- Status bar color. -->
+        <item name="android:statusBarColor">?attr/colorPrimaryVariant</item>
+        <!-- Customize your theme here. -->
+    </style>
 </resources>