为什么不活动的onDestroy一个没有被称为一个电话后完成（）在ActivityB [英] Why onDestroy inActivity A not being called after a call to finish() in ActivityB

问题描述

接下来的过程简单理解和再现，但导致错误：

The next process is simple to understand and to reproduce but leads to a bug:

• activityA开始在其的onCreate（）方法
的activityB
• activityB被创建，我称之为完成（）在onResume（）方法
• activityB 的onDestroy（）叫
• activityA onResume（）叫
• ，并在这里activityA，我点击菜单按钮来调用完成（） - 或preSS返回键
• activityA被删除，但的onDestroy（）不叫，并且A还活着（亚行外壳dumpsysmyPackageName表示太多的生活活动）

• activityA starts an activityB in its onCreate() method
• activityB is created and I call finish() in its onResume() method
• activityB onDestroy() is called
• activityA onResume() is called
• and here in activityA, I click a menu button to call finish() - or press the back key.
• activityA is removed but onDestroy() is NOT called and A is still living ( adb shell dumpsys 'myPackageName' indicates too many living Activities )

code

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="gleroy.com.algo">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme">
        <activity
            android:name=".activity.MainActivity"
            android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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


        <activity
            android:name="gleroy.com.algo.activity.FakeA"
            android:label="@string/app_name"></activity>

        <activity
            android:name="gleroy.com.algo.activity.FakeB"
            android:label="@string/app_name"></activity>
    </application>
</manifest>

活动答：

public class FakeA extends Activity {

    private final static String TAG = FakeA.class.getCanonicalName();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        Log.d(TAG, "onCreate, taskId :" + getTaskId());
        super.onCreate(savedInstanceState);

        Intent intent = new Intent(FakeA.this, FakeB.class);
        startActivity(intent);
    }

    @Override
    protected void onResume() {
        Log.d(TAG, "onResume");
        super.onResume();
    }


    @Override
    protected void onDestroy() {
        Log.d(TAG, "onDestroy");
        super.onDestroy();
    }

    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        super.onCreateOptionsMenu(menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {

        switch (item.getItemId()) {
            case R.id.stop_session_menu_item:
                /* stop and quit */
                finish();
                return false;
        }

        return super.onOptionsItemSelected(item);
    }
}

活动B：

public class FakeB extends Activity {

    private final static String TAG = FakeB.class.getCanonicalName();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        Log.d(TAG, "onCreate, taskId :"+getTaskId());
        super.onCreate(savedInstanceState);
    }

    @Override
    protected void onResume() {
        super.onResume();
        Log.d(TAG, "onResume, isFinishing :" + isFinishing());
        finish();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        Log.d(TAG, "onDestroy");
    }
}

活动A从MainActivity开始，其中包含一个简单的按钮：

Activity A is started from MainActivity which contains a simple button :

 @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    findViewById(R.id.btn).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent = new Intent(MainActivity.this, FakeA.class);
            startActivity(intent);
        }
    });

所以，我知道，我们不能保证的onDestroy（）是要去被称为但是我在这里的ActivityA显然泄漏。

So I know that we can't be sure that onDestroy() is gonna be called but here my ActivityA is clearly leaking.

此外，我认为，如果我使用定时器和的TimerTask 延迟 startActivity 在ActivityA或完成（）在ActivityB话，我就没有这个错误了。

Also I observed that if I use a Timer and TimerTask to delay startActivity in ActivityA or finish() in ActivityB then I don't have this bug anymore.

下面是事件：

• FakeA的onCreate，TASKID：154
• FakeA onResume
• FakeA的onPause，isFinishing：假
• FakeB的onCreate，TASKID：154
• FakeB onResume，isFinishing：假
• FakeA onResume
• FakeB的onDestroy
• 在通话结束或preSS返回键：FakeA的onPause，isFinishing：真正的

推荐答案

在地方的结束（）尝试 finishAffinity（）。 我所知道的： 完成（）只是破坏当前动态活动 同时， finishAffinity（）摧毁所有活动活动。

In place of finish() try finishAffinity(). As far as i know: finish() just destroys the current live Activity while, finishAffinity() destroys all active Activities.

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