AlarmManager fires alarms in the past immediately before BroadcastReceiver can reschedule it

Question

I have a BroadcastReceiver which reschedules alarms on events such as booting and time change. But when the time is past the trigger time of the alarm (For example, when the user manually changes the time from the settings), AlarmManager fires the alarm immediately before I can add a day to reschedule my alarm. How can I avoid this?

I'm currently using the set and add methods of the Calendar to schedule the alarms.

        for (int dayOfWeek = Calendar.SUNDAY; dayOfWeek <= Calendar.SATURDAY; dayOfWeek++) {
            if (alarm.getRepeatingDay(dayOfWeek - 1) && dayOfWeek >= nowDay &&
                    !(dayOfWeek == nowDay && alarm.timeHour < nowHour) &&
                    !(dayOfWeek == nowDay && alarm.timeHour == nowHour && alarm.timeMinute <= nowMinute)) {

                calendar.set(Calendar.DAY_OF_WEEK, dayOfWeek);
                alarmSet = true;
                break;
            }
        }

        if (!alarmSet) {
            for (int dayOfWeek = Calendar.SUNDAY; dayOfWeek <= Calendar.SATURDAY; dayOfWeek++) {
                if (alarm.getRepeatingDay(dayOfWeek - 1) && dayOfWeek <= nowDay) {
                    calendar.set(Calendar.DAY_OF_WEEK, dayOfWeek);
                    calendar.add(Calendar.WEEK_OF_YEAR, 1);
                    break;
                }
            }
        }

It is also stated in the docs:

If the stated trigger time is in the past, the alarm will be triggered immediately.

How can this behaviour be altered?

Answer 1

This is intended. See e.g. Set a Repeating Alarm

A trigger time. If the trigger time you specify is in the past, the alarm triggers immediately.

or the same here

If the stated trigger time is in the past, the alarm will be triggered immediately.

To avoid this you will have to either manually check your alarms before adding them,

if(alarmTimeStamp < System.currentTimeMillis()) {
    // if is repeating schedule in __interval__
    // else ignore
}

or ignore them in your receiver if the date is in the past.