Fragment和Activity生命週期以及橫豎屏切換對生命週期的影響

轉自：http://www.androidchina.net/5024.html

Fragment生命週期圖解，fragment和activity生命週期對比

生命週期變化 : 切換到該Fragment

05-21 14:26:35.095: D/FragmentDemo(7649): onAttach
 05-21 14:26:35.095: D/FragmentDemo(7649): onCreate
 05-21 14:26:35.095: D/FragmentDemo(7649): onCreateView
 05-21 14:26:35.100: D/FragmentDemo(7649): onActivityCreated
 05-21 14:26:35.120: D/FragmentDemo(7649): onStart
 05-21 14:26:35.120: D/FragmentDemo(7649): onResume

屏幕滅掉：

05-21 14:27:35.185: D/FragmentDemo(7649): onPause
 05-21 14:27:35.205: D/FragmentDemo(7649): onSaveInstanceState
 05-21 14:27:35.205: D/FragmentDemo(7649): onStop

屏幕解鎖

05-21 14:33:13.240: D/FragmentDemo(7649): onStart
 05-21 14:33:13.275: D/FragmentDemo(7649): onResume

切換到其他Fragment:

05-21 14:33:33.655: D/FragmentDemo(7649): onPause
 05-21 14:33:33.655: D/FragmentDemo(7649): onStop
 05-21 14:33:33.660: D/FragmentDemo(7649): onDestroyView

切換回本身的Fragment:

05-21 14:33:55.820: D/FragmentDemo(7649): onCreateView
 05-21 14:33:55.825: D/FragmentDemo(7649): onActivityCreated
 05-21 14:33:55.825: D/FragmentDemo(7649): onStart
 05-21 14:33:55.825: D/FragmentDemo(7649): onResume

回到桌面

05-21 14:34:26.590: D/FragmentDemo(7649): onPause
 05-21 14:34:26.880: D/FragmentDemo(7649): onSaveInstanceState
 05-21 14:34:26.880: D/FragmentDemo(7649): onStop

回到應用

05-21 14:36:51.940: D/FragmentDemo(7649): onStart
 05-21 14:36:51.940: D/FragmentDemo(7649): onResume

退出應用

05-21 14:37:03.020: D/FragmentDemo(7649): onPause
 05-21 14:37:03.155: D/FragmentDemo(7649): onStop
 05-21 14:37:03.155: D/FragmentDemo(7649): onDestroyView
 05-21 14:37:03.165: D/FragmentDemo(7649): onDestroy
05-21 14:37:03.165: D/FragmentDemo(7649): onDetach

新建一個Activity，在各個生命週期中輸出log

1、按crtl+f12切換成橫屏時

onSaveInstanceState-->

onPause-->

onStop-->

onDestroy-->

onCreate-->

onStart-->

onRestoreInstanceState-->

onResume-->

2、再按crtl+f12切換成豎屏時，發現打印了兩次相同的log

 onSaveInstanceState-->
 onPause-->
 onStop-->
 onDestroy-->
 onCreate-->
 onStart-->
 onRestoreInstanceState-->
 onResume-->
 onSaveInstanceState-->
 onPause-->
 onStop-->
 onDestroy-->
 onCreate-->
 onStart-->
 onRestoreInstanceState-->
 onResume-->

3、修改AndroidManifest.xml，把該Activity添加 Android:configChanges=”orientation”，執行步驟2，橫屏切換爲豎屏

 onSaveInstanceState-->
 onPause-->
 onStop-->
 onDestroy-->
 onCreate-->
 onStart-->
 onRestoreInstanceState-->
 onResume-->

4、再執行步驟2，豎屏切換爲橫屏，發現不會再打印相同信息，但多打印了一行onConfigChanged

 onSaveInstanceState-->
 onPause-->
 onStop-->
 onDestroy-->
 onCreate-->
 onStart-->
 onRestoreInstanceState-->
 onResume-->
 onConfigurationChanged-->

5、把步驟3的android:configChanges=”orientation” 改成 android:configChanges=”orientation|keyboardHidden”，執行步驟2，豎屏切換橫屏，就只打印onConfigChanged

 onConfigurationChanged-->

8、再次執行步驟2，橫屏切換回豎屏

 onConfigurationChanged-->

總結：
1、不設置Activity的android:configChanges時，切屏會重新調用各個生命週期，切橫屏時會執行一次，切豎屏時會執行兩次

2、設置Activity的android:configChanges=”orientation”時，切屏還是會重新調用各個生命週期，切橫、豎屏時只會執行一次

3、設置Activity的android:configChanges=”orientation|keyboardHidden”時，切屏不會重新調用各個生命週期，只會執行onConfigurationChanged方法