在Android 4上重复通知

Question

Goal: Notification appears everyday once, at 2 PM, if certain condition is met.

Example: For simplicity, let's consider that the condition, checked with Internet connection, is met everyday. If today is already after 2 PM, we we'll start notifications from tomorrow. For example, user starts app at 4 PM on Monday, and he gets notifications on Tuesday 2 PM, Wednesday 2 PM, Thursday 2 PM and so on.

Problem: At 2 PM there is a first notification, but then I get the same notification over and over again, at random times.

Problem seems to be only on Android >= 4.0. It works good on earlier Androids.

This is how I send notification:

public class NotifyService extends Service
{       
static final int NOTIFICATION_ID = 1;
// ...

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

@Override
public int onStartCommand(Intent intent, int flags, int startId)
{
    try
    {
        Symbol biggest = getBiggestMover();
        if (biggest != null)
        {
            String title = getString(R.string.app_name);
            String text = getNotificationText(biggest.symbol, biggest.change);
            sendNotification(title, text);
        }
    }
    catch (Exception e)
    {
        // If there is Internet problem we do nothing, don't want to disturb the user.
        e.printStackTrace();
    }

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

/** @return Symbol which is the biggest mover today. If there is no big mover - null is returned.
 * @throws Exception If there is Internet problem. */
private Symbol getBiggestMover() throws Exception
{
    Symbol biggest = null;
    Symbol[] equities = Network.getTraded(SymbolType.EQUITY);
    for (Symbol equity : equities)
    {
        if (Utilities.isToday(equity.lastTraded) && isBigMove(equity.change) && isBigger(equity, biggest))
        {
            biggest = equity;
        }
    }
    return biggest;
}   

private void sendNotification(String title, String text)
{
    Notification notification = new Notification(R.drawable.ic_launcher, text, System.currentTimeMillis());
    notification.flags = Notification.FLAG_AUTO_CANCEL;

    Intent clickIntent = new Intent(this, MainActivity.class);
    PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, clickIntent, PendingIntent.FLAG_CANCEL_CURRENT);

    notification.setLatestEventInfo(this, title, text, pendingIntent);

    NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    manager.notify(NOTIFICATION_ID, notification);
}   
// ...  
}

sendNotification() is called at 2 PM, because of the AlarmManager :

public class ServiceStarter extends BroadcastReceiver
{

@Override
public void onReceive(Context context, Intent intent)
{
    setNotificationAlarm(context);
}

/** Set repeating notifications every 24 hours. */
public static void setNotificationAlarm(Context context)
{
    Intent intent = new Intent(context, NotifyService.class);
    AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    PendingIntent pendingIntent = PendingIntent.getService(context, 0, intent, PendingIntent.FLAG_CANCEL_CURRENT);

    final int oneDay = 24 * 60 * 60 * 1000;
    alarmManager.setRepeating(AlarmManager.RTC, getTriggerTime(), oneDay, pendingIntent);
}

private static long getTriggerTime()
{
    GregorianCalendar calendar = new GregorianCalendar();
    calendar.set(GregorianCalendar.HOUR_OF_DAY, 14);
    calendar.set(GregorianCalendar.MINUTE, 0);
    calendar.set(GregorianCalendar.SECOND, 0);
    calendar.set(GregorianCalendar.MILLISECOND, 0);

    if (calendar.before(new GregorianCalendar()))
    {
        calendar.add(GregorianCalendar.DAY_OF_MONTH, 1);
    }

    return calendar.getTimeInMillis();
}

}

setNotificationAlarm() is called from 2 places. First, at the start of app. Second, from the code above, when the phone reboots ( onReceive() receives BOOT_COMPLETED ). I do that, because when the user turns the phone off, AlarmManager clears its alarms.

So all should work, because alarmManager.setRepeating() overrides previous alarm.

I have found that somebody had the same issue, but also no answer:
https://groups.google.com/forum/?fromgroups=#!topic/android-developers/t_tDU4PwR3g

Also here I found similar problem: http://comments.gmane.org/gmane.comp.handhelds.android.devel/171471

Some time ago I asked how to create such notifications, so this is related:
Everyday notifications at certain time

Answer 1

Use AlarmManager.RTC_WAKEUP insted of AlarmManager.RTC

In AlarmManager.RTC

Alarm time in System.currentTimeMillis() (wall clock time in UTC). This alarm does not wake the device up; if it goes off while the device is asleep, it will not be delivered until the next time the device wakes up.

where as in AlarmManager.RTC_WAKEUP

Alarm time in System.currentTimeMillis() (wall clock time in UTC), which will wake up the device when it goes off.

Answer 2

Had the same problem on ICS+ device. My workaround was very simple-> Put the current time in the shared preferences when the notification is shown. Before that always check if the interval is really passed, and if not just abort.

            long lastnotification = sharedPrefs.getLong("lnnd", -1);
            Calendar now = Calendar.getInstance();
            if (!namedayalarmEnabled) {
                    return;
            }
            if (lastnotification > 1) {
                    Calendar last = Calendar.getInstance();
                    last.setTimeInMillis(lastnotification);
                    long distance = (now.getTimeInMillis() - last
                                    .getTimeInMillis());
                    if (distance < YOURINTERVAL) {
                            return;
                    } else {
                            SharedPreferences.Editor editor = sharedPrefs.edit();
                            editor.putLong("lnnd", now.getTimeInMillis());
                            editor.commit();
                    }
            }