@Override

public boolean onKeyDown(int keyCode, KeyEvent event) {

//按下键盘上返回按钮

if(keyCode == KeyEvent.KEYCODE_BACK){

new AlertDialog.Builder(this)

.setIcon(R.drawable.services)

.setTitle(R.string.prompt)

.setMessage(R.string.quit_desc)

.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

}

})

.setPositiveButton(R.string.confirm, new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int whichButton) {

finish();

}

}).show();

return true;

}else{

return super.onKeyDown(keyCode, event);

}

}

@Override

protected void onDestroy() {

super.onDestroy();

System.exit(0);

//或者下面这种方式

//android.os.Process.killProcess(android.os.Process.myPid());

}