private void CalendarAppointmentUpdated(object sender, AppointmentChangedEventAgrs e)
        {
            string notification;

            switch (e.OccurrenceAction)
            {
            case OccurrenceAction.Add:
                notification = String.Format("Exception occurence on {0:d} of the recurrent Appointment `{1}` was created.", e.Occurrence.ExceptionDate, e.Appointment.Title);
                break;

            case OccurrenceAction.Update:
                notification = String.Format("Exception occurence on {0:d} of the recurrent Appointment `{1}` was updated.", e.Occurrence.ExceptionDate, e.Appointment.Title);
                break;

            case OccurrenceAction.Delete:
                notification = String.Format("The occurence on {0:d} of the recurrent Appointment `{1}` was deleted.", e.Occurrence.ExceptionDate, e.Appointment.Title);
                break;

            default:
                notification = String.Format("Appointment `{0}` was updated", e.Appointment.Title);
                break;
            }
            Application.Current.MainPage.DisplayAlert("Appointment Change", notification, "OK");
        }
 private void CalendarAppointmentDeleted(object sender, AppointmentChangedEventAgrs e)
 {
     Application.Current.MainPage.DisplayAlert("Appointment Change", String.Format("Appointment with title `{0}` was deleted.", e.Appointment.Title), "OK");
 }