android - 奇怪的 Activity 生命周期。

Question

当我第一次从我的主要 Activity 开始一个 Activity 时，它会通过 onCreate() 然后 onStart()。在应用程序中，如果我关闭屏幕，它会转到我保存一些数据的 onPause()。然后立即转到 onStop()，然后是 onDestroy()，然后再次，不打开屏幕到 onCreate()、onStart()、onPause()。
它是否应该在 onDestroy() 之后立即转到 onCreate()、onStart()，而不需要我做任何事情？

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setContentView(R.layout.activity_timegame);

}

@Override
protected void onResume() {
    super.onStart();
    if (checkFirstTimeRun())
        initializeGame();
    else
        resumeGame();
}

@Override
protected void onPause() {
    super.onPause();
    saveGameData();
}

Answer 1

简短说明( Considering you are not using fragments ) :

Activity 创建是OnCreate , OnStart , OnResume

旋转屏幕时OnPause , OnStop , OnDestroy - 再次OnCreate , OnStart , OnResume因为 Activity 被销毁并重新创建 onOrientation 更改

因此，如果您不旋转 OnCreate , OnStart , OnResume不是第二次开除!

了解执行哪些事件以及何时执行:

Have a look at one of my answers i posted in stackoverflow - Click Here

用例示例( Considering you are using fragments):

示例项目 :

I have an opensource project Download it here and execute it and see the log to understand >the sequence of events executes one after another(I have fragment also in this project exclude the >fragment logs if you don't need it)

项目观察

如果路径是Activity - FragmentOne并第一次改变方向然后触发的事件如下MainActivity-onCreate -FragmentOne-onAttach -FragmentOne-onCreate -FragmentOne-onCreateView -FragmentOne-onActivityCreated -FragmentOne-onStart -FragmentOne-onResume

如果路径是Activity - FragmentOne - orientationchange并第一次改变方向然后触发的事件如下

MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onPause - FragmentOne-onSaveInstanceState - FragmentOne-onStop - FragmentOne-onDestroy - FragmentOne-onDetach - MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume

如果路径是Activity - FragmentOne - orientationchange - orientationchange并第一次改变方向然后触发的事件如下

MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onPause - FragmentOne-onSaveInstanceState - FragmentOne-onStop - FragmentOne-onDestroy - FragmentOne-onDetach - MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onPause - FragmentOne-onSaveInstanceState - FragmentOne-onStop - FragmentOne-onDestroy - FragmentOne-onDetach - MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume

如果路径是Activity - FragmentOne - orientationchange - orientationchange - FragmentTwo并第一次改变方向然后触发的事件如下

MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onPause - FragmentOne-onSaveInstanceState - FragmentOne-onStop - FragmentOne-onDestroy - FragmentOne-onDetach - MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onPause - FragmentOne-onSaveInstanceState - FragmentOne-onStop - FragmentOne-onDestroy - FragmentOne-onDetach - MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onStop - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentTwo-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume

如果路径是Activity - FragmentOne - orientationchange - orientationchange - FragmentTwo - orientationchange并第一次改变方向然后触发的事件如下

MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onPause - FragmentOne-onSaveInstanceState - FragmentOne-onStop - FragmentOne-onDestroy - FragmentOne-onDetach - MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onPause - FragmentOne-onSaveInstanceState - FragmentOne-onStop - FragmentOne-onDestroy - FragmentOne-onDetach - MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentOne-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onStop - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentTwo-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume - FragmentOne-onPause - FragmentOne-onSaveInstanceState - FragmentOne-onSaveInstanceState - FragmentOne-onStop - FragmentOne-onDestroy - FragmentOne-onDetach - FragmentOne-onDestroy - FragmentOne-onDetach - MainActivity-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onAttach - FragmentOne-onCreate - FragmentOne-onCreateView - FragmentTwo-onActivityCreated - FragmentOne-onStart - FragmentOne-onResume