[移动开发]Activity和Fragment生命周期

Activity

1. 进入页面
   onCreate - onStatrt - onResume — onRestart - onPause - onStop - onDestroy

Fragment

1. 创建
   onAttach - onCreate - onCreateView - onViewCreated - onActivityCreated - onStart - onResume

2. 销毁
   onPause - onStop - onDestroyView - onDestroy - onDetach

3. home键／熄屏／进入任务页
   onPause - onSaveInstanceState - onStop

4. home后重进／亮屏／任务页重进
   onStart - onResume

ViewPager2中的Fragment的生命周期

前提: 3个Fragment, setOffscreenPageLimit(x) Fragment会比x预创建一个

1. 进入页面(x1)

   2022-02-23 11:29:36.729 A/(AFragment.java:52)(onAttach): ---> "1"
   2022-02-23 11:29:36.730 A/(AFragment.java:58)(onCreate): ---> "2"
   2022-02-23 11:29:36.731 A/(AFragment.java:63)(onCreateView): ---> "3"
   2022-02-23 11:29:36.734 A/(AFragment.java:70)(onViewCreated): ---> "4"
   2022-02-23 11:29:36.758 A/(AFragment.java:76)(onActivityCreated): ---> "5"
   2022-02-23 11:29:36.759 A/(AFragment.java:82)(onViewStateRestored): ---> "6"
   2022-02-23 11:29:36.760 A/(AFragment.java:88)(onStart): ---> "7"
   2022-02-23 11:29:36.776 A/(AFragment.java:94)(onResume): ---> "8"
   
   2022-02-23 11:29:36.779 E/(BFragment.java:47)(onAttach): ---> "1"
   2022-02-23 11:29:36.780 E/(BFragment.java:53)(onCreate): ---> "2"
   2022-02-23 11:29:36.781 E/(BFragment.java:58)(onCreateView): ---> "3"
   2022-02-23 11:29:36.784 E/(BFragment.java:65)(onViewCreated): ---> "4"
   2022-02-23 11:29:36.800 E/(BFragment.java:71)(onActivityCreated): ---> "5"
   2022-02-23 11:29:36.801 E/(BFragment.java:77)(onViewStateRestored): ---> "6"
   2022-02-23 11:29:36.803 E/(BFragment.java:83)(onStart): ---> "7"
   

2. 从A滑到BFragment(此时先创建C,再执行AB的生命周期)

   W/(CFragment.java:46)(onAttach): ---> "1"
   W/(CFragment.java:52)(onCreate): ---> "2"
   W/(CFragment.java:57)(onCreateView): ---> "3"
   W/(CFragment.java:64)(onViewCreated): ---> "4"
   W/(CFragment.java:70)(onActivityCreated): ---> "5"
   W/(CFragment.java:76)(onViewStateRestored): ---> "6"
   W/(CFragment.java:82)(onStart): ---> "7"
   
   A/(AFragment.java:101)(onPause): ---> "-1"
   
   E/(BFragment.java:89)(onResume): ---> "8"
   

3. 在2的基础上(从B退出), 退出页面
   当前的Fragment会pause,其他的按照ABC顺序执行

   E/(BFragment.java:96)(onPause): ---> "-1"
   A/(AFragment.java:107)(onStop): ---> "-2"
   E/(BFragment.java:102)(onStop): ---> "-2"
   W/(CFragment.java:101)(onStop): ---> "-2"
   A/(AFragment.java:113)(onDestroyView): ---> "-3"
   A/(AFragment.java:119)(onDestroy): ---> "-4"
   A/(AFragment.java:125)(onDetach): ---> "-5"
   E/(BFragment.java:108)(onDestroyView): ---> "-3"
   E/(BFragment.java:114)(onDestroy): ---> "-4"
   E/(BFragment.java:120)(onDetach): ---> "-5"
   W/(CFragment.java:107)(onDestroyView): ---> "-3"
   W/(CFragment.java:113)(onDestroy): ---> "-4"
   W/(CFragment.java:119)(onDetach): ---> "-5"