[Android] exit 확인창 출력

Back key를 눌렀을때, 종료 확인창을 출력..
한번 더누르면 종료 처리..

@Override
 protected Dialog onCreateDialog(int id) {
  switch(id)
  {
   case DIALOG_QUIT:
    return new AlertDialog.Builder(this)
    .setMessage("Are you sure you want to leave the game?")
    .setPositiveButton("YES", new DialogInterface.OnClickListener() {
    
     @Override
     public void onClick(DialogInterface dialog, int which) {
      finish();
     }
    })
    .setNegativeButton("NO", new DialogInterface.OnClickListener() {
    
     @Override
     public void onClick(DialogInterface dialog, int which) {
      dialog.dismiss();
     }
    })
    .setOnKeyListener(new DialogInterface.OnKeyListener() {
           @Override
           public boolean onKey (DialogInterface dialog, int keyCode, KeyEvent event) {
               if (keyCode == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_UP && !event.isCanceled()) {
                dialog.dismiss();
                finish();
                   return true;
               }
               return false;
           }
       }).create();
   
    //break;
  
   default:
    break;
  }
 
  return null;
 }