问Android前台服务通知不持久

EN

@Override
public void onCreate()
{
    super.onCreate();

    initialize();
}

private void initialize()
{
    Notification n = get_service_notification();
    startForeground(10, n);

    LocalBroadcastManager.getInstance(this).registerReceiver(mMessageReceiver, new IntentFilter(BroadcastCodes.service_broadcast_intent_name));
}

@Override
public int onStartCommand(Intent intent, int flags, int startId)
{
    startServing();
    return START_STICKY;
}

private Notification get_service_notification()
{
    Intent intent = new Intent(this, LoginActivity.class);
    PendingIntent contentIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);

    NotificationCompat.Builder b = new NotificationCompat.Builder(this);

    b.setAutoCancel(false)
            .setWhen(System.currentTimeMillis())
            .setSmallIcon(R.drawable.app_icon)
            .setTicker("some text")
            .setContentTitle("some text")
            .setContentText("some text")
            .setContentIntent(contentIntent)
            .setContentInfo("")
            .setOngoing(true);

    Notification res = b.build();
    res.flags |= Notification.FLAG_ONGOING_EVENT | Notification.FLAG_NO_CLEAR;

    return res;
}

notificationManager.notify(10, service_notification);