How to exit the Android program by pressing the back key

The main purpose is to enable the program to exit when you press the back key.

Implementation ideas:
1. The event is triggered when the back key event is captured.

Copy codeThe Code is as follows: @ Override
Public boolean onKeyDown (int keyCode, KeyEvent event ){
// If you press BACK, there are no duplicates at the same time
If (keyCode = KeyEvent. KEYCODE_BACK & event. getRepeatCount () = 0 ){
// DO SOMETHING
....
}
Return true;
}

2. Exit the program when the backend key is pressed.
There are also two ways: exit the program directly or exit to the main screen.

1) Two Ways to exit the program:

Android. OS. Process. killProcess (android. OS. Process. myPid ());

System. exit (0 );

I tried these two methods, But the strange thing is that in the 1.5 simulator, the program was indeed killed, but Android immediately restarted the program.

In addition, there is another method that is friendly and can release resources. I think it is feasible, that is, it is a little troublesome to implement it. You need to exit step by step and rewrite the onResume () method:

Copy codeThe Code is as follows: @ Override
Protected void onResume (){
Super. onResume ();
If (mExiting ){
Finish ();
}
}

2) exit to the home screen (recommended)
This is relatively simple. You can create an Intent for the home screen.Copy codeThe Code is as follows: Intent home = new Intent (Intent. ACTION_MAIN );
Home. setFlags (Intent. FLAG_ACTIVITY_CLEAR_TOP );
Home. addCategory (Intent. CATEGORY_HOME );
StartActivity (home );