ActivtyA跳转ActivityB然后按back返回A,各自的生命周期顺序（B为透明、非透明时）

1.ActivityB为非透明主题

ActiityA跳转ActivityB：

Activity A：onPause
Activity B：onCreate
Activity B：onStart
Activity B：onResume
Activity A：onStop

ActivityB返回ActivityA：

Activity B：onPause
Activity A：onRestart
Activity A：onStart
Activity A：onResume
Activity B：onStop
Activity B：onDestroy

2.ActivityB为透明主题

设置ActivityB为透明主题

<activity
    android:name="com.example.translucent.TranslucentActivity"
    android:theme="@android:style/Theme.Translucent.NoTitleBar.Fullscreen"
    />

ActiityA跳转ActivityB：

Activity A：onPause
Activity B：onCreate
Activity B：onStart
Activity B：onResume

ActivityB返回ActivityA：

Activity B：onPause
Activity A：onResume
Activity B：onStop
Activity B：onDestroy