AlarmManager not adding new Alarms, or not trigger

Question

I'm currently developing an application which makes use of Android's AlarmManager. I'm trying to add a new alarm to the AlarmManager, but after several hours of trying various things and checking various threads on SO, I'm still at a brick wall. Are there any problems with my code?

---

Main Activity - saveAlarm() function

/**
 * Saves the current alarm. Adds to the database if it doesn't already exist, or updates if it does.
 * Also sets alert with AlarmManager.
 */
public void saveAlarm() {
    // Create Database instance
    DbHandler db = new DbHandler(getApplicationContext());

    if(alarm.getId() == -1) {
        // Saving a new alarm
        db.open();
        alarm.setId(db.addAlarm(alarm));
        db.close();
    }
    else {
        db.open();
        db.updateAlarm(alarm);
        db.close();
    }

    // Create the wakeup intent
    Intent intent = new Intent(this, AlarmReceiver.class);
    intent.putExtra("alarm_id", alarm.getId());

    // Create the Pending Intent
    PendingIntent sender = PendingIntent.getBroadcast(this, AlarmPlayer.REQUEST_ALARM + alarm.getId(), intent, PendingIntent.FLAG_UPDATE_CURRENT);

    // Debug
    Calendar now = Calendar.getInstance();
    long dTime  = alarm.getNextAlarmTime().getTimeInMillis() - now.getTimeInMillis();
    Log.d(TAG, "Setting alarm for " + (dTime / 1000) + " seconds time");

    // Add to Android Alarm Manager
    AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
    am.set(AlarmManager.RTC_WAKEUP, alarm.getNextAlarmTime().getTimeInMillis(), sender);    
}

I've verified that the correct time is being passed into am.set (see the debug section above it).

---

AlarmReceiver.class

/**
* This class listens out for broadcasts from AlarmManager
* and launches the AlarmPlayer activity accordingly.
* @author Michael
*
*/
public class AlarmReceiver extends BroadcastReceiver {

     @Override
    public void onReceive(Context c, Intent intent) {
        Log.d("RSS Alarm", "Waking up alarm");
            // Launch the AlarmPlayer activity
        Intent i = new Intent(c, AlarmPlayer.class);
        i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        c.startActivity(i);
    }

}

---

I also have <receiver android:process=":remote" android:name="AlarmReceiver" /> set up in AndroidManifest.xml. I have no idea what's causing this problem, but it's happening nonetheless. Any help would be greatly appreciated, many thanks in advance.

---

Edit 1 Changing the timezone to UTC doesn't seem to solve anything, my calendar seems to default to UTC regardless. Current code:

// Debug
Calendar now = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
long dTime  = alarm.getNextAlarmTime().getTimeInMillis() - now.getTimeInMillis();
Log.d(TAG, "Setting alarm for " + (dTime / 1000) + " seconds time");

// Add to Android Alarm Manager
AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
Log.d(TAG, "Timezone offset is " + TimeZone.getDefault().getRawOffset());
Log.d(TAG, "UTC time is currently " + Calendar.getInstance(TimeZone.getTimeZone("UTC")).getTimeInMillis() / 1000);
am.set(AlarmManager.RTC_WAKEUP, (alarm.getNextAlarmTime().getTimeInMillis() - TimeZone.getDefault().getRawOffset()), sender);

Answer 1

In your manifest, I believe you need android:name".AlarmReceiver" note the dot. If that doesn't do it, post your manifest file. Also, does your logcat mention adding alarm and alarm triggering?

Edit: You might try this AlarmManager am = (AlarmManager) getSystemService(Context.ALARM_SERVICE);

Other than that, I don't see anything jumping out at me. Good Luck

Answer 2

Is this possibly a case that AlarmManager.set(AlarmManager.RTC_WAKEUP, ...) needs the time in UTC? This causes problems if you're setting a 'local time' and don't adjust to UTC. In short, the alarm may be being properly added but it doesn't trigger when you expect it unless your time-zone is UTC.

From the docs...

public static final int RTC_WAKEUP Since: API Level 1

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