public GuestViewModel(GuestView guestView, string username)
 {
     this.guestView           = guestView;
     MenuList                 = menu.GetMenu();
     Username                 = username;
     backgroundWorker         = new BackgroundWorker();
     backgroundWorker.DoWork += CheckIfApprovedOrRejected;
     //checking whether the guest has an order
     if (newOrder.CheckIfUserOrdered(username) == false)
     {
         newOrder.CreateOrder(Username);
         Ordered    = newOrder.ViewOrder(Username);
         totalPrice = Ordered.TotalPrice;
     }
     //if has order
     else
     {
         IsVisibleMenu        = Visibility.Hidden;
         OrderList            = orderItems.GetOrderedItems(Username);
         IsVisibleOrderStatus = Visibility.Visible;
         IsConfirmed          = Visibility.Hidden;
         Ordered    = newOrder.ViewOrder(Username);
         totalPrice = Ordered.TotalPrice;
         //running background worker
         backgroundWorker.RunWorkerAsync();
     }
 }