Activity启动-关闭

1、启动

从 MainActivity.java --> DetailActivity.java
mainActivity.java

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button button = (Button) findViewById(R.id.button1);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(MainActivity.this,DetailActivity.class);
                startActivity(intent);
            }
        });
    }
}

activity_main.xml

<Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="查看详细"
        tools:ignore="MissingConstraints" />

mainfests 功能清单

<activity android:name=".MainActivity">
   <intent-filter>
        <action android:name="android.intent.action.MAIN" />

        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>
<activity android:name=".DetailActivity"
    android:label="详细"/>

效果

点击按钮后跳转到详细页面。

2、关闭

detailActivity.java 调用finish即可

public class DetailActivity extends Activity {

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_detail);
        Button button =(Button) findViewById(R.id.button2);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                finish();
            }
        });
    }
}