java - 无法使 Google Cloud Message 保持 Activity 状态

Question

我正在尝试解决 gcm 超时问题，关于这个主题有很多话题，这里是 one供引用。

建议的解决方法是以比 tcp 超时更短的间隔广播一对 Intent 。

我的实现是创建一个扩展 CountDownTimer 类的类，并在现有服务中保存该类的一个实例。这个派生类在完成后自行重启，服务被标记为 STICKY_START，所以一旦启动，我认为它应该每 4 分钟继续广播一次 Intent ，但由于某种原因存在间隙，当计数器不广播 Intent ，我仍然与 GCM 服务器失去联系。

下面是两个相关的类。谁能解释并提供解决方案，说明为什么此策略不起作用？

我创建了一个扩展 CounDownTimer 的类，它应该每 4 分钟广播一次 Intent 。

public class GcmKeepAlive extends CountDownTimer {

    protected CountDownTimer timer;
    protected Context mContext;
    protected Intent gTalkHeartBeatIntent;
    protected Intent mcsHeartBeatIntent;


    public GcmKeepAlive(Context context) {
        super(4*60* 1000,4*60*1000);
        mContext = context;
        gTalkHeartBeatIntent = new Intent("com.google.android.intent.action.GTALK_HEARTBEAT");
        mcsHeartBeatIntent = new Intent("com.google.android.intent.action.MCS_HEARTBEAT");
        System.out.println("stariing heartbeat countdown timer");
        this.start();
    }


    @Override
    public void onTick(long millisUntilFinished) {

    }

    @Override
    public void onFinish() {
        System.out.println("sending heart beat to keep gcm alive");
        mContext.sendBroadcast(gTalkHeartBeatIntent);
        mContext.sendBroadcast(mcsHeartBeatIntent);
        this.start();

    }

}

这是我的应用程序中的服务，它包含 GcmKeepAlive 类的实例

导入android.app.Service；导入 android.content.Intent；导入android.os.IBinder;

public class LocationMonitorService extends Service {

    private DeviceLocationClient deviceLocationClient;
    private GcmKeepAlive gcmKeepAlive;

    @Override
    public void onCreate() {
        // TODO Auto-generated method stub
        super.onCreate();
        System.out.println("creating the LocationMonitorService");
        deviceLocationClient = new DeviceLocationClient(this);
        gcmKeepAlive = new GcmKeepAlive(this);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        // TODO Auto-generated method stub
        System.out.println("inside service making request for location updates");
        deviceLocationClient.requestLLocationUpdates();
        gcmKeepAlive.start();
        return START_STICKY;
    }

    @Override
    public IBinder onBind(Intent intent) {
        // TODO Auto-generated method stub
        return null;
    }


}

这是一个在 logcat 中看到的差距示例。

07-13 14:59:05.583 I/System.out(21651): sending heart beat to keep gcm alive
07-13 15:03:05.640 I/System.out(21651): sending heart beat to keep gcm alive
07-13 15:07:05.776 I/System.out(21651): sending heart beat to keep gcm alive
07-13 15:11:05.922 I/System.out(21651): sending heart beat to keep gcm alive
07-13 15:27:31.994 I/System.out(21651): sending heart beat to keep gcm alive

Answer 1

我实际上在前一段时间解决了这个问题，Erik Z 最近的评论让我发布了我的解决方案。

我通过创建一个触发广播的循环警报解决了这个问题，该广播创建并广播了 Intent 。这些差距是由于原始服务被终止然后由于 START_STICKY 标志而重新启动造成的。

这是各个部分(从各种文件中提取)

这至少是 kitkat 之前需要的，我不知道是否仍然需要，我想是的。但是我没有关闭它来确认。

---

警报管理器、 Intent 和未决 Intent 。

AlarmManager alarmManager = (AlarmManager) Context.getSystemService(Context.ALARM_SERVICE);

Intent gcmKeepAliveIntent = new Intent("com.gmail.npnster.ourlatitude.gcmKeepAlive");

PendingIntent gcmKeepAlivePendingIntent = PendingIntent.getBroadcast(mContext, 0, gcmKeepAliveIntent, PendingIntent.FLAG_CANCEL_CURRENT);

alarmManager.setInexactRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP, 1000, 4*60*1000, gcmKeepAlivePendingIntent);

---

广播接收器:

public class GcmKeepAliveBroadcastReceiver extends BroadcastReceiver {

    private GcmKeepAlive gcmKeepAlive;

    @Override
    public void onReceive(Context context, Intent intent) {
        MyLog.p(this,"inside gcm keep alive receiver");
        gcmKeepAlive = new GcmKeepAlive(context);
        gcmKeepAlive.broadcastIntents();

    }

}

---

发送保活广播的保活类。

public class GcmKeepAlive  {

    protected Context mContext;
    protected Intent gTalkHeartBeatIntent;
    protected Intent mcsHeartBeatIntent;

    public GcmKeepAlive(Context context) {
        mContext = context;
        gTalkHeartBeatIntent = new Intent(
                "com.google.android.intent.action.GTALK_HEARTBEAT");
        mcsHeartBeatIntent = new Intent(
                "com.google.android.intent.action.MCS_HEARTBEAT");  
    }

    public void broadcastIntents() {
        MyLog.p(this,"sending heart beat to keep gcm alive");
        mContext.sendBroadcast(gTalkHeartBeatIntent);
        mContext.sendBroadcast(mcsHeartBeatIntent);
    }

}