Second call to AlarmManager.setRepeating() gets delivered at wrong time

Question

My application executes the following code:

// Check intakes every 15 minutes
Intent i = new Intent(this, IntakeReceiver.class);
i.putExtra("TYPE", "TAKEIN_CHECK");
PendingIntent pi = PendingIntent.getBroadcast(getApplicationContext(), 0, i, 0);

AlarmManager am = (AlarmManager)(this.getSystemService(Context.ALARM_SERVICE));
Calendar cal = Calendar.getInstance();
int offset = 1000 * 60 * 15; // 1000 * 60 * 15 (15 minutes)
long nowLastRounded = cal.getTimeInMillis() - (cal.getTimeInMillis() % offset);
am.setRepeating(AlarmManager.RTC_WAKEUP, nowLastRounded + offset, offset, pi);

// Also set alarm for 11:50 every day to notify about low stock
Intent i2 = new Intent(this, LowStockReceiver.class);
i2.putExtra("TYPE", "STOCK_CHECK");
PendingIntent pi2 = PendingIntent.getBroadcast(getApplicationContext(), 1, i2, 0);

long interval_day = AlarmManager.INTERVAL_DAY;
long interval_hour = AlarmManager.INTERVAL_HOUR;
int offset2 = 1000 * 60 * 60 * 11 + 1000 * 60 * 50; // 11:50

final int tzOffset = TimeZone.getDefault().getOffset(System.currentTimeMillis());
offset2 -= tzOffset;

nowLastRounded = cal.getTimeInMillis() - (cal.getTimeInMillis() % interval_day);
am.setRepeating(AlarmManager.RTC_WAKEUP, nowLastRounded + offset2, interval_hour, pi2);

The problem is that the LowStockReceiver.onReceive() is called every 15 minutes (like the IntakeReceiver.onReceive() ) but it should only be called every hour starting from 11:50.

I have checked the value of nowLastRounded + offset2 and it equals the local time today at 11:50 converted to GMT. So it should run at 11:50, 12:50, 13:50, etc. (just for testing purposes currently).

Anyone have any idea what I could be doing wrong?

Thank you!

Answer 1

您对两个警报使用相同的ID作为待定意图。请使用不同的ID。

Answer 2

Solved my own problem.

The problem was two-fold but the question didn't contain enough details for the question to be solvable:

• Above code was called as a static function from the main Application class which could get instantiated by the first alarm.

• This caused the second alarm to be rescheduled, and the time appeared to be in the past, causing it to be fired immediately and confusing me.