title: Android - How to reschedule alarms associated to app events
body: <p>I found a lot of examples and questions regarding how to fire an alarm using AlarmManager (both periodical or single), but nothing similar to what I need.</p>
  
  <p>My user can schedule a certain number of events (i.e. things to do), with a <em>single-shot</em> alarm for each of them to be fired one day before the scheduled start (showing a notification). This is easy.
  My problem is that this scheduled start can be changed, thus the alarm should be moved too.</p>
  
  <p>I was thinking to delete the old alarm, and to create a new one considering the new scheduled start. Knowing that I can delete an alarm using <code>alarmMgr.cancel(alarmIntent)</code>, how can I delete the specific alarm related to the rescheduling event? Should I make each alarmIntent unique in some way?
  Or there is a better way that I didn't consider (except using Google Calendar APIs to schedule and reschedule an event there, and making it managing the notification)?</p>