private void SaveButton_Click(object sender, System.EventArgs e)
        {
            Program     app         = Program.GetInstance();
            ShowService showService = app.GetService <ShowService>("shows");

            // Parse values
            Movie movie = (Movie)movieInput.SelectedItem;
            Room  room  = (Room)roomInput.SelectedItem;

            if (movie == null)
            {
                GuiHelper.ShowError("Je moet een film kiezen");
                return;
            }

            if (room == null)
            {
                GuiHelper.ShowError("Je moet een zaal kiezen");
                return;
            }

            // Create and save show
            Show show = new Show(movie.id, room.id, datetimeInput.Value);

            if (!showService.SaveShow(show))
            {
                GuiHelper.ShowError(ValidationHelper.GetErrorList(show));
                return;
            }

            // Redirect to screen
            ShowDetail showDetail = app.GetScreen <ShowDetail>("showDetail");

            showDetail.SetShow(show);
            app.ShowScreen(showDetail);
            GuiHelper.ShowInfo("Voorstelling succesvol aangemaakt");
        }