java - Activity 重现和闪烁

Question

我有 FirstRunActivity 和 MainActivity(启动器)。当应用程序打开时，如果应用程序是第一次打开，我会启动 FirstRunActivity(清除 Activity 历史记录)。

一切正常。但是当在设备中打开自动旋转，然后使用旋转的设备打开应用程序时，屏幕闪烁。在日志中，我可以看到 Activity 在循环中重新创建。

日志:

3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onPause
04-17 22:49:00.390    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStop
04-17 22:49:00.410    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStart
04-17 22:49:00.410    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onResume
04-17 22:49:00.480    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onPause
04-17 22:49:00.480    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStop
04-17 22:49:00.520    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStart
04-17 22:49:00.520    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onResume
04-17 22:49:00.630    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onPause
04-17 22:49:00.630    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStop
04-17 22:49:00.680    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStart
04-17 22:49:00.680    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onResume
04-17 22:49:00.800    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onPause
04-17 22:49:00.810    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStop
04-17 22:49:00.870    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStart
04-17 22:49:00.870    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onResume
04-17 22:49:00.960    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onPause
04-17 22:49:00.970    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStop
04-17 22:49:00.990    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStart
04-17 22:49:00.990    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onResume
04-17 22:49:01.060    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onPause
04-17 22:49:01.060    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStop
04-17 22:49:01.080    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStart
04-17 22:49:01.080    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onResume
04-17 22:49:01.150    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onPause
04-17 22:49:01.150    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStop
04-17 22:49:01.180    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStart
04-17 22:49:01.180    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onResume
04-17 22:49:01.250    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onPause
04-17 22:49:01.250    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStop
04-17 22:49:01.280    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onStart
04-17 22:49:01.280    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onResume
04-17 22:49:01.430    3028-3028/tm.mobile.payment D/SazHyzmat﹕ FirstRunActivity onPause

FirstRunActivity.java :

public class FirstRunActivity extends ActionBarActivity {

    @InjectView(R.id.password) EditText passwordView;
    @InjectView(R.id.password_retype) EditText passwordRetypeView;
    @InjectView(R.id.save) View saveButton;

    @Override
    protected void onCreate( Bundle savedInstanceState ) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_first_run);
        ButterKnife.inject(this);
    }

    @Override protected void onStart() {
        super.onStart();
        U.l("FirstRunActivity onStart");
    }

    @Override protected void onStop() {
        super.onStart();
        U.l("FirstRunActivity onStop");
    }

    @Override protected void onPause() {
        super.onStart();
        U.l("FirstRunActivity onPause");
    }

    @Override protected void onResume() {
        super.onStart();
        U.l("FirstRunActivity onResume");
    }
}

主要 Activity .java :

@Override
    protected void onCreate( Bundle savedInstanceState ) {
        super.onCreate(savedInstanceState);
        settingsManager = SettingsManager.getInstance(this);
        //If app not initialized
        if (! settingsManager.isAppInitialized()) {
            Intent intent = new Intent(this, FirstRunActivity.class);
            intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
            ComponentName cn = intent.getComponent();
            Intent mainIntent = IntentCompat.makeRestartActivityTask(cn);
            startActivity(mainIntent);
               finish();
        } else {
            //Other code
        }
}

如果我更改启动首次运行 Activity 的代码(在 MainActivity.java 中)， Activity 不会闪烁，但当按下后退按钮时，它将打开 MainActivity 并显示白屏。或者用其他方式清除 Activity 历史记录:Clear the entire history stack and start a new activity on Android无论如何屏幕​​都在闪烁。

那么我怎样才能停止闪烁并清除 Activity 历史记录呢？

编辑

测试后我发现在我的其他 Activity 中，与上述代码无关，有同样的问题，闪烁。使用旋转设备打开 Activity 时。

Answer 1

查看 IntentCompat.makeRestartActivityTask 的文档，听起来它创建了一个用于重新启动当前 Activity 的 Intent 。我建议删除这两行:

ComponentName cn = intent.getComponent();
Intent mainIntent = IntentCompat.makeRestartActivityTask(cn);

我在改变 Activity 时从不需要它们。

此外，对 mContext.finish() 的调用可以只用 finish() 完成，并且在这种情况下永远不能为空，很可能你看到白屏的原因是 mContext 为空，所以你永远不会成功完成了该 Activity 。