AlarmManager-设置为10分钟时不会关闭

Question

基本上，此代码的工作方式是...它从初始计算开始，然后在X分钟后通过Alarmmanager启动服务，该服务获得结束计算并确定两者之间的差。 在每个警报结束时，将在相同的时间间隔内设置一个新警报。 当我将时间间隔设置为10分钟时，警报根本不会响起。

我假设这与手机CPU进入休眠状态有关，因为这是我数天来一直在尝试使用多种编写此算法的方法来解决的问题。

如果有人对这是为什么有任何线索，将不胜感激，因为这对我程序的功能非常重要。 附带一提，这段代码可以在5分钟之内完美无缺地运行，只要插入10，我一无所获。

从我的服务

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

    // Set return value
    int retVal = START_NOT_STICKY;

    if (intent != null) {

        System.out.println("Service Thread: " + Thread.currentThread().getName());

        // Set up context reference for getObject
        self = this;

        // Set up global intent reference
        theIntent = intent;

        // Get data
        getData();

        // Enter foreground state
        String title = "The service has been started...";
        String subject = "Service is running.";
        String body = "Monitoring your battery usage...";
        Notification notification = new Notification(R.drawable.theicon, title,
                System.currentTimeMillis());
        if (notificationSounds)
            notification.defaults |= Notification.DEFAULT_SOUND;
        else
            notification.sound = null;
        Intent notificationIntent = new Intent(this, MainActivity3.class);
        PendingIntent pendIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);
        notification.setLatestEventInfo(this, subject, body, pendIntent);
        startForeground(1500, notification);

        // Calculate wait time (convert from minutes to ms)
        int waitTime = interval * 60000;
       // int waitTime = 15000; // Debug 15 second wait

        // Get initial battery
        int initialBatt = getBatteryPercent();

        // Debug
        System.out.println("Initial battery percent: " + initialBatt);

        // Get current time
        Calendar c = Calendar.getInstance();
        Date dateNow = c.getTime();
        long timeNow = dateNow.getTime(); // Time in MS

        // Set up alarm manager to wait and then execute next step
        AlarmManager AM = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
        svcIntent1 = new Intent(Service.getObject(), AlarmReceiver.class);
        svcIntent1.putExtra("timeToUse", timeToUse);
        svcIntent1.putExtra("interval", interval);
        svcIntent1.putExtra("rawTime", rawTime);
        svcIntent1.putExtra("initialBatt", initialBatt);
        svcIntent1.putExtra("sounds", notificationSounds);
        pendingIntent = PendingIntent.getBroadcast(Service.getObject(), 0, svcIntent1, PendingIntent.FLAG_UPDATE_CURRENT);

        // Set up the next alarm
        System.out.println("The current time is " + dateNow.
        SimpleDateFormat sdf = new SimpleDateFormat("MM-dd hh:mm:ss a");
        Toast.makeText(this, "The current time is " + sdf.format(dateNow), Toast.LENGTH_LONG).show();
        Date n = new Date();
        n.setTime(timeNow+waitTime);
        System.out.println("Next calculation will complete at " + sdf.format(n));
        Toast.makeText(this, "Next calculation will complete at " + sdf.format(n), Toast.LENGTH_LONG).show();
        AM.setExact(AlarmManager.RTC_WAKEUP, timeNow + waitTime, pendingIntent);
    }
    return retVal;
}

我的广播接收器类中的onReceive

@Override
public void onReceive(Context c, Intent intent) {
    if(intent != null){
        // Get app context
        context = Service.getObject();

        Toast.makeText(context, "Alarm broadcast received.", Toast.LENGTH_SHORT).show();

        // Set up the intent
        theIntent = intent;

        // Get the extra data
        getData();

        // Do calculations and get new initial battery level for next alarm
        int endBatt = calculateHelper(initialBatt);

        // Set up alarm manager to wait and then execute next step
        AlarmManager AM = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
        Intent svcIntent1 = new Intent(Service.getObject(), AlarmReceiver.class);
        svcIntent1.putExtra("timeToUse", timeToUse);
        svcIntent1.putExtra("interval", interval);
        svcIntent1.putExtra("rawTime", rawTime);
        svcIntent1.putExtra("initialBatt", endBatt);
        svcIntent1.putExtra("sounds", context.notificationSounds);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(Service.getObject(), 0, svcIntent1, PendingIntent.FLAG_UPDATE_CURRENT);

        // Get times
        long timeNow = dateNow.getTime();
        int waitTime = interval * 60000;


        // Debug stuff
        // int waitTime = 15000;
        SimpleDateFormat sdf = new SimpleDateFormat("MM-dd hh:mm:ss a");
        System.out.println("The current time is " + sdf.format(dateNow));
        Toast.makeText(context, "The current time is " + sdf.format(dateNow), Toast.LENGTH_LONG).show();
        Date n = new Date();
        n.setTime(timeNow+waitTime);
        System.out.println("Next calculation will complete at " + sdf.format(n));
        Toast.makeText(context, "Next calculation will complete at " + sdf.format(n), Toast.LENGTH_LONG).show();

        // Setting the next alarm
        AM.setExact(AlarmManager.RTC_WAKEUP, timeNow + waitTime, pendingIntent);
    }
    else
        notify0(10,"ERROR", "ERROR", "Intent is null", true);
}

在我的清单上...

    <receiver
        android:name=".AlarmReceiver"
        android:enabled="true"
        android:exported="true" >
    </receiver>

---

我的新代码（感谢Larry Schiefer的建议）

我还发现，即使WakefulBroadcastReceiver持有WakeLock，如果操作系统要关闭该服务，也可以在不使用WakeLock的情况下重新启动它。 因此，有时有必要获取额外的唤醒锁以在onStartCommand中进行处理。 就我而言，这是必需的。

为我服务

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

    // Acquire WakeLock
    PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
    PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "Service WakeLock");
    wl.acquire();

    // Set up global intent reference
    theIntent = intent;

    if (theIntent != null) {
        getData();
        if (intent.getAction().equals("Start_Interval")) {
            doStart();
        }
        else if(intent.getAction().equals("End_Interval")){
            doEnd();
        }
    }
    else{
        Log.e("ERROR", "The intent is NULL inside of onStartCommand. Activity closed?");
        cancelAlarm();
        stopSelf();
    }

    // Release WakeLock
    wl.release();

    return START_STICKY;
}

我的onReceive-将“扩展BroadcastReceiver”更改为“扩展WakefulBroadcastReceiver”

@Override
public void onReceive(Context c, Intent intent) {
    if(intent != null){

        // Debug
        Log.d("Debug","Alarm broadcast received.");

        // Set up the global intent reference
        theIntent = intent;

        // Set up service context reference
        context = Service.getObject();

        // Get data from the intent
        getData();

        // Set up the new intent
        Log.d("Debug", "Setting up new intent with context: " + c + " and class: " + Service.class);
        Intent service = new Intent(c, Service.class);
        service.putExtra("timeToUse", timeToUse);
        service.putExtra("interval", interval);
        service.putExtra("rawTime", rawTime);
        service.putExtra("initialBatt", initialBatt);
        service.setAction("End_Interval");

        // Wake up the service and complete this interval's calculations
         startWakefulService(c, service);
    }
    else {
        context.cancelAlarm();
        context.stopSelf();
    }
}

Answer 1

在您的BroadcastReceiver使用Log而不是Toast来验证是否已接收到广播。 一旦系统进入低功耗状态，RTC_WAKEUP就会将其唤醒，但仅在您的onReceive执行期间。 此后，系统将释放警报的唤醒锁，并且系统甚至可以在屏幕上还没有显示我们的吐司消息之前就进入睡眠状态。 如果您需要服务根据警报实际执行某些操作，则需要使用自己的唤醒锁来协调接收器和服务，以确保系统正常运行（请参阅WakefulBroadcastReceiver 。）