@Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        Log.d("Service", "onStartCommand() begin");
        new Thread(new Runnable() {
            @Override
            public void run() {
                // 開始執行後台任務
                Log.d("Service", "onStartCommand() executed");
            }
        }).start();

        Log.d("Service", "onStartCommand() end");

        return super.onStartCommand(intent, flags, startId);
    }