Beverage Window

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Collections.ObjectModel;

namespace Wawa_TouchScreen
    {
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
    public partial class Window1 : Window
        {
        public string foodItemName;
        public double price;
        public string message = "You ordered a ";
        Receipt foodItem = new Receipt();

        // This shared list will display all items on the Listbox.
        ObservableCollection<Receipt> orderList = new ObservableCollection<Receipt>();

        Window2 checkOut = new Window2();

        public Window1()
            {
            InitializeComponent();
            }

        private void cancelBtn1_Click(object sender, RoutedEventArgs e)
            {
            MessageBoxResult result = MessageBox.Show("Are you sure you want to cancel your order?", "Cancel Order", MessageBoxButton.YesNo);

            if (result == MessageBoxResult.Yes)
                {
                this.Close();
                Application.Current.Shutdown();
                }
            }

        private void previousBtn1_Click(object sender, RoutedEventArgs e)
            {
            MainWindow mainMenu = new MainWindow();
            mainMenu.Show();
            this.Visibility = Visibility.Hidden;
            }

        private void frozenSmoothieBtn_Click(object sender, RoutedEventArgs e)
            {
            foodItemName = "Frozen Smoothie";
            message += foodItemName;
            price = 1.99;

            AddFoodItem(foodItemName, price, foodItem, orderList);

            CheckOutShow(message);
        }

        private void frozenCappuccinoBtn_Click(object sender, RoutedEventArgs e)
            {
            foodItemName = "Frozen Cappucino";
            message += foodItemName;
            price = 1.99;

            AddFoodItem(foodItemName, price, foodItem, orderList);

            CheckOutShow(message);
            }

        // AddFoodItem will add foodItem to lstBoxReceipt and display the info on lstBoxReceipt

        private void AddFoodItem(string foodItemName, double price, Receipt foodItem, ObservableCollection<Receipt> orderList)
            {
            this.foodItemName = foodItemName;
            this.price = price;
            this.orderList = orderList;
            this.foodItem = foodItem;

            foodItem = new Receipt(foodItemName, price);

            orderList.Add(foodItem);

            checkOut.lstBoxReceipt.ItemsSource = orderList;
            }

        private void CheckOutShow(string message)
            {
            this.message = message;

            MessageBox.Show(message);
            checkOut.Show();
            this.Visibility = Visibility.Hidden;
            }
        }
    }