Here's answer
finishAffinity() is not used to "shutdown an application". It is used to remove a number of Activitys belonging to a specific application from the current task (which may contain Activitys belonging to multiple applications).
Even if you finish all of the Activitys in your application, the OS process hosting your app does not automatically go away (as it does when you call System.exit()). Android will eventually kill your process when it gets around to it. You have no control over this (and that is intentional).
you can use this
public void endTask() {
// Is the user running Lollipop or above?
if (Build.VERSION.SDK_INT >= 21) {
// If yes, run the fancy new function to end the app and
// remove it from the task list.
finishAndRemoveTask();
} else {
// If not, then just end the app without removing it from
// the task list.
finish();
}
}
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