Comparison of the life cycles of Fragment and Activity in Android

Fragment must exist dependent on Activity, so the life cycle of Activity will directly affect the life cycle of Fragment. This picture on the official website illustrates the relationship between the two very well:

# You can see that Fragment has several additional life cycle callback functions than Activity:

onAttach(Activity);　　//当Activity与Fragment发生关联时调用
 
onCreateView(LayoutInflater,ViewGroup,Bundle);　　//创建该Fragment的视图
 
onActivityCreate(bundle);　　//当Activity的onCreate()；方法返回时调用
 
onDestoryView();　　//与onCreateView相对应，当改Fragment被移除时调用
 
onDetach();　　//与onAttach()相对应，当Fragment与Activity的关联被取消时调用

Note: Except for onCreateView, if you override all other methods, you must call the parent class's implementation of this method.

Scene demonstration:

Switch to this Fragment

11-29 14:26:35.095: D/AppListFragment(7649): onAttach
11-29 14:26:35.095: D/AppListFragment(7649): onCreate
11-29 14:26:35.095: D/AppListFragment(7649): onCreateView
11-29 14:26:35.100: D/AppListFragment(7649): onActivityCreated
11-29 14:26:35.120: D/AppListFragment(7649): onStart
11-29 14:26:35.120: D/AppListFragment(7649): onResume

Screen off:

11-29 14:27:35.185: D/AppListFragment(7649): onPause
11-29 14:27:35.205: D/AppListFragment(7649): onSaveInstanceState
11-29 14:27:35.205: D/AppListFragment(7649): onStop

Screen unlock

11-29 14:33:13.240: D/AppListFragment(7649): onStart
11-29 14:33:13.275: D/AppListFragment(7649): onResume

Switch to other Fragment :

11-29 14:33:33.655: D/AppListFragment(7649): onPause
11-29 14:33:33.655: D/AppListFragment(7649): onStop
11-29 14:33:33.660: D/AppListFragment(7649): onDestroyView

Switch back to your own Fragment:

11-29 14:33:55.820: D/AppListFragment(7649): onCreateView
11-29 14:33:55.825: D/AppListFragment(7649): onActivityCreated
11-29 14:33:55.825: D/AppListFragment(7649): onStart
11-29 14:33:55.825: D/AppListFragment(7649): onResume

Back to the desktop

11-29 14:34:26.590: D/AppListFragment(7649): onPause
11-29 14:34:26.880: D/AppListFragment(7649): onSaveInstanceState
11-29 14:34:26.880: D/AppListFragment(7649): onStop

##Back to the application

11-29 14:36:51.940: D/AppListFragment(7649): onStart
11-29 14:36:51.940: D/AppListFragment(7649): onResume

Exit the application

11-29 14:37:03.020: D/AppListFragment(7649): onPause
11-29 14:37:03.155: D/AppListFragment(7649): onStop
11-29 14:37:03.155: D/AppListFragment(7649): onDestroyView
11-29 14:37:03.165: D/AppListFragment(7649): onDestroy
11-29 14:37:03.165: D/AppListFragment(7649): onDetach

It has more life cycles than Activity, and is completely connected to Activity. Everyone can take advantage of it.

For more articles related to the life cycle comparison of Fragment and Activity in Android, please pay attention to the PHP Chinese website!