android 闹钟管理器在几个小时后停止

Question

我创建了一个每 5 秒启动一次服务的警报管理器，该应用程序运行良好但几个小时后警报管理器停止运行。请注意，该应用程序未被用户使用，这意味着它在没有用户交互的情况下在后台运行。有谁知道如何每隔几秒启动一次服务而不停止？

AlarmManager am = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(context, AlarmManagerBroadcastReceiver.class);
intent.putExtra(ONE_TIME, Boolean.TRUE); 
PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);
am.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + (1000 * 60 * 5), pi); 

Answer 1

不要对警报管理器做这样的事情。报警管理器更多应该在几个小时内完成的任务的概念(在最佳情况下)。

如果您需要精确处理您的任务，请在内部使用处理程序服务，该帖子执行您的可运行。在您的 runnable 中，调用该方法以再次执行 runnable。

将runnable和handler保存为服务的成员变量并make过程很粘。如果你想停止服务和处理程序(处理程序不会如果你只是调用 stopService(Context) 或 Service.stopSelf()，你需要停止在处理程序上使用您的可运行对象调用 removeCallbacks(runnable)。

干杯。

顺便说一句:考虑一下您是否真的想要每 5 秒启动一次服务。也许只是在服务的可运行内部做服务工作我刚刚描述了。

Edit2:如果您需要服务可靠，请为启动操作添加一个 BroadcastReceiver，它将在启动时接收广播并重新启动您的服务。

Edit3:在不启动服务的情况下检查您的服务是否正在运行的代码:

    public static boolean isRunning(Context context) {
    ActivityManager manager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
    for (ActivityManager.RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE)) {
        if (YourService.class.getName().equals(service.service.getClassName())){
            return true;
        }
    }
    return false;
}

但是，尽管如此，请在 onStartCommand 中检查您的成员“处理程序”是否为空如果是这样，请忽略启动请求，因为这可能会导致您遇到多个可运行处理的情况。

编辑4:

服务代码 fragment :

public class LoopingServiceSnipped extends Service{

public static final long STANDARD_FREQUENCY = 1000;
private static       long         loopingFrequency         = STANDARD_FREQUENCY;
private Handler  serviceHandler; 
private Runnable loop; 

//EXTRAS

private static final String       INTENT_EXTRA_STOP_SERVICE  = LoopingServiceSnipped.class.getSimpleName() + "_INTENT_EXTRA_STOP_SERVICE";
private static final String       INTENT_EXTRA_FREQUENCY     = LoopingServiceSnipped.class.getSimpleName() + "_INTENT_EXTRA_FREQUENCY";

/**
 * Determines if the service is running (reliably) without starting it.
 *
 * @param context
 *         needed for SystemServices
 *
 * @return true if the service is running
 */
public static boolean isRunning(Context context) {
    ActivityManager manager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
    for (ActivityManager.RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE)) {
        if (LoadingScreenAppDetectionService.class.getName().equals(service.service.getClassName())){
            return true;
        }
    }
    return false;
}

public static void stopService(Context c) {
    Intent i = new Intent(c, LoopingServiceSnipped 
    i.putExtra(INTENT_EXTRA_STOP_SERVICE, true);
    c.startService(i);
 }

public static synchronized void setFrequency(Context c, long frequency) {
    Intent i = new Intent(c, LoadingScreenAppDetectionService.class);
    i.putExtra(INTENT_EXTRA_FREQUENCY, frequency);
    c.startService(i);
}

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

private void init() {
    //do your initialization here
}

@Nullable
@Override
public IBinder onBind(Intent intent) {
    return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    if (shouldStopService(intent)){
        LOG.d("Going to stop service!");
        tryStopService();
        return Service.START_NOT_STICKY;
    } else {
        return startOrContinueService(intent);
    }
}

private void tryStopService() {
    stopLooping();
    stopSelf();
}

private void stopLooping() {
    if (serviceHandler != null){
        serviceHandler.removeCallbacks(getLoop());
        serviceHandler = null;
    }
}

private int startOrContinueService(Intent intent) {
    if (hasNewFrequency(intent)){
        setFrequency(intent);
        stopLooping();
    }
    if (!isServiceRunning()){
     startLooping();
        }
    } else {
        LOG.d("Going to continue with service!");
    }
    return Service.START_STICKY;
}


private boolean hasNewFrequency(Intent intent) {
    return intent.hasExtra(INTENT_EXTRA_FREQUENCY);
}

private void setFrequency(Intent intent) {
    if (intent.hasExtra(INTENT_EXTRA_FREQUENCY)){
        loopingFrequency = intent.getLongExtra(INTENT_EXTRA_FREQUENCY, STANDARD_FREQUENCY);
    }
}

private boolean isServiceRunning() {
    return serviceHandler != null;
}

private boolean shouldStopService(Intent i) {
    if (i.hasExtra(INTENT_EXTRA_STOP_SERVICE)){
        return i.getBooleanExtra(INTENT_EXTRA_STOP_SERVICE, false);
    } else {
        return false;
    }
}

private void startLooping() {
    if (serviceHandler == null){
        serviceHandler = new Handler();
    }
    serviceHandler.postDelayed(getAppDetectionLoop(), getFrequency());
}

private Runnable getLoop() {
    if (loop == null){
        loop = new Runnable() {
            @Override
            public void run() {
                //do your looping work here
                startLooping();
            }
        };
    }
    return loop;
}

另外添加Boot Receiver和Screen TurnOn Receiver。