private void GuestGridView_ItemClick(object sender, ItemClickEventArgs e)
        {
            var model = e.ClickedItem as EventGuest;

            if (model.GuestStatus == GustArrivalStatus.Unknown)
            {
                model.GuestStatus = GustArrivalStatus.Arrived;
            }
            else if (model.GuestStatus == GustArrivalStatus.Arrived)
            {
                model.GuestStatus = GustArrivalStatus.ArrivedLate;
            }
            else if (model.GuestStatus == GustArrivalStatus.ArrivedLate)
            {
                model.GuestStatus = GustArrivalStatus.DidNotCome;
            }
            else
            {
                model.GuestStatus = GustArrivalStatus.Unknown;
            }

            SqLiteManager.UpdateAttendance(model);
        }