Just modify the code alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent) in AndroidAlarmService class to alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), 5*1000, pendingIntent).
public void onClick(View arg0) {
   // TODO Auto-generated method stub
  
   Intent myIntent = new Intent(AndroidAlarmService.this, MyAlarmService.class);
   pendingIntent = PendingIntent.getService(AndroidAlarmService.this, 0, myIntent, 0);
            AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE);
            Calendar calendar = Calendar.getInstance();
            calendar.setTimeInMillis(System.currentTimeMillis());
            calendar.add(Calendar.SECOND, 10);
            //alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent);
            alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), 5*1000, pendingIntent);
          
   Toast.makeText(AndroidAlarmService.this, "Start Alarm", Toast.LENGTH_LONG).show();
  }});
public void setRepeating (int type, long triggerAtTime, long interval, PendingIntent operation), like set(int, long, PendingIntent), except you can also supply a rate at which the alarm will repeat.
Related article:
- App Widget using Alarm Manager
