@Override

public boolean dispatchKeyEvent(KeyEvent event) {

// TODO Auto-generated method stub

if(event.getAction() == KeyEvent.ACTION_DOWN && event.getKeyCode() == KeyEvent.KEYCODE_BACK){

showDialog();

return false;

}

return super.dispatchKeyEvent(event);

}

public void showDialog(){

final CheckBox check = new CheckBox(this);

check.setText("退出后仍然接收通知 ?");

new AlertDialog.Builder(this)

.setTitle(R.string.app_name)

.setView(check)

.setNegativeButton("取消", new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).setPositiveButton("确定", new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

if(check.isSelected() == true){

startBackService();

}

System.exit(0);

finish();

}

})

.show();

}