Fragment和Activity生命週期以及橫豎屏切換對生命週期的影響

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

切換到其餘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

切換回自己的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
一、按crtl+f12切換成橫屏時
onSaveInstanceState-->
onPause-->
onStop-->
onDestroy-->
onCreate-->
onStart-->
onRestoreInstanceState-->
onResume-->

二、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-->

三、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-->

四、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-->

五、把步驟3的android:configChanges="orientation" 改爲 android:configChanges="orientation|keyboardHidden"，執行步驟2，豎屏切換橫屏，就只打印onConfigChanged
onConfigurationChanged-->

八、再次執行步驟2，橫屏切換回豎屏
onConfigurationChanged-->

 總結：
一、不設置Activity的android:configChanges時，切屏會從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

二、設置Activity的android:configChanges="orientation"時，切屏仍是會從新調用各個生命週期，切橫、豎屏時只會執行一次
 

三、設置Activity的android:configChanges="orientation|keyboardHidden"時，切屏不會從新調用各個生命週期，只會執行onConfigurationChanged方法