onWindowFocus--onAttachedToWindow--onWindowVisibilityChanged--onWindowFocusChanged

1: entry: onStart---->onResume---->onAttachedToWindow----------->onWindowVisibilityChanged--visibility=0---------->onWindowFocusChanged(true)------->

2. exit: onPause---->onStop---->onWindowFocusChanged(false) ---------------------- (lockscreen)

3, exit : onPause----->onWindowFocusChanged--false-------->Launcher.Workspace, onWindowVisibilityChanged--visibility=8------------>onStop (to another activity)

4,