最新消息:欢迎访问Android开发中文站!商务联系微信:loading_in

Fragment和Activity生命周期以及横竖屏切换对生命周期的影响

新手入门 AndroidChina 3222浏览 0评论

Fragment生命周期图解,fragment和activity生命周期对比

生命周期变化 : 切换到该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

屏幕灭掉:

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

屏幕解锁

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

切换到其他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

切换回本身的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

回到应用

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

退出应用

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

新建一个Activity,在各个生命周期中输出log

1、按crtl+f12切换成横屏时

onSaveInstanceState-->

onPause-->

onStop-->

onDestroy-->

onCreate-->

onStart-->

onRestoreInstanceState-->

onResume-->

2、再按crtl+f12切换成竖屏时,发现打印了两次相同的log

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

3、修改AndroidManifest.xml,把该Activity添加 Android:configChanges=”orientation”,执行步骤2,横屏切换为竖屏

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

4、再执行步骤2,竖屏切换为横屏,发现不会再打印相同信息,但多打印了一行onConfigChanged

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

5、把步骤3的android:configChanges=”orientation” 改成 android:configChanges=”orientation|keyboardHidden”,执行步骤2,竖屏切换横屏,就只打印onConfigChanged

 onConfigurationChanged-->

8、再次执行步骤2,横屏切换回竖屏

 onConfigurationChanged-->

总结:
1、不设置Activity的android:configChanges时,切屏会重新调用各个生命周期,切横屏时会执行一次,切竖屏时会执行两次

2、设置Activity的android:configChanges=”orientation”时,切屏还是会重新调用各个生命周期,切横、竖屏时只会执行一次

3、设置Activity的android:configChanges=”orientation|keyboardHidden”时,切屏不会重新调用各个生命周期,只会执行onConfigurationChanged方法

转载请注明:Android开发中文站 » Fragment和Activity生命周期以及横竖屏切换对生命周期的影响

您必须 登录 才能发表评论!