Question

I have a receiver that start after phone boot like this:

<receiver android:name=".OnBootReceiver" >
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED" />
            </intent-filter>

</receiver>

in the receiver I run set an alarm like this:

AlarmManager  mgr=(AlarmManager)context.getSystemService(Context.ALARM_SERVICE);

        Intent i=new Intent(context, LocationPoller.class);

        i.putExtra(LocationPoller.EXTRA_INTENT,
                  new Intent(context, LocationReceiver.class));
        i.putExtra(LocationPoller.EXTRA_PROVIDER,
                 LocationManager.GPS_PROVIDER);



         PendingIntent pi=PendingIntent.getBroadcast(context, 0, i, 0);
          mgr.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP,
                        SystemClock.elapsedRealtime(),
                        PERIOD,
                        pi);

It works fine, except, of course, when user install app, the alarm will not be set until user reboot phone,.

to go around this, I need to check from my Activity if AlarmManager is set, if not I need to set from Activity.

Hence, how do I check if Alarm manager is already set.

Answer 1

Sadly, you cant query AlarmManager for current Alarms.

Best option to solve your problem would be to cancel your current Alarm and set a new one.

You just have to create an intent that matches the one in the reciever. More info here

so add this to your activity

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

     Intent i=new Intent(context, LocationPoller.class);

        i.putExtra(LocationPoller.EXTRA_INTENT,
                  new Intent(context, LocationReceiver.class));
        i.putExtra(LocationPoller.EXTRA_PROVIDER,
                 LocationManager.GPS_PROVIDER);

        PendingIntent pi=PendingIntent.getBroadcast(context, 0, i, 0);
    // Cancel alarms
    try {
        AlarmManager.cancel(pi);
    } catch (Exception e) {
        Log.e(TAG, "AlarmManager update was not canceled. " + e.toString());
    }
mgr.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP,
                        SystemClock.elapsedRealtime(),
                        PERIOD,
                        pi);

You probably need to change the context of the intent so its the same as the one in the Reciever.

Another Workaround would be to detect if its the first start of the App, and only start it then. But then what happens if user reboots his phone before the first start?