How to set an alarm to fire properly at fixed time?

Question

I have this code

Calendar c = new GregorianCalendar();
        c.add(Calendar.DAY_OF_YEAR, 1);
        c.set(Calendar.HOUR_OF_DAY, 23);
        c.set(Calenda         


        

Answer 1

You are using the AlarmManager.ELAPSED_REALTIME_WAKEUP flag, but you are using a Calendar object. These two things don't go together.

You need to use AlarmManager.RTC or AlarmManager.RTC_WAKEUP if you are specifying the alarm time using a Calendar or Date object (milliseconds since 1970).

You use AlarmManager.ELAPSED_REALTIME or AlarmManager.ELAPSED_REALTIME_WAKEUP when you are specifying the alarm time via SystemClock.elapsedRealtime() (milliseconds since the phone booted).