private void saveBtnClicked(object sender, RoutedEventArgs e)
{
if (!ValidateFields())
{
return;
}
Model.Reservation tempReservation = staffMenu.ObservableReservations[reservationList.SelectedIndex];
reservationList.SelectedIndex = -1;
MyController.manageReservation.SaveReservation(tempReservation, tempReservation.ReservationId);
staffMenu.updateReservationList();
reservationList.Items.Refresh();
}