Time/Date change listener

Question

I want to make a time or date listener which for example invoke an activity every day at 9 AM. I am not sure what is the best way to do that? I know I can use Alarm Manager,

Answer 1

I know I can use Alarm Manager, but I don't know how to make it repetitive?

Use setRepeating() and specify a repeat interval of INTERVAL_DAY:

    static void scheduleAlarms(Context ctxt) {
      AlarmManager mgr=(AlarmManager)ctxt.getSystemService(Context.ALARM_SERVICE);
      Intent i=new Intent(ctxt, ScheduledService.class);
      PendingIntent pi=PendingIntent.getService(ctxt, 0, i, 0);

      mgr.setRepeating(AlarmManager.ELAPSED_REALTIME,
                       SystemClock.elapsedRealtime() + AlarmManager.INTERVAL_DAY,
                       AlarmManager.INTERVAL_DAY, pi);
  }

The above code will set up an alarm that will go off 24 hours from right now and every 24 hours thereafter. To have it start at 9am, replace ELAPSED_REALTIME with RTC and replace SystemClock.elapsedRealtime() + AlarmManager.INTERVAL_DAY with 9am (today or tomorrow), such as via a Calendar object.