feat: 上传第三次安卓课程代码(2026年10月09日)

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
+     */
+}