private void CarModel_SelectionChanged(object sender, SelectionChangedEventArgs e)
 {
     if (CarModel.SelectedIndex == -1
         ||
         CarColor.SelectedIndex == -1
         ||
         CarEngine.SelectedIndex == -1
         ||
         CarType.SelectedIndex == -1
         )
     {
         return;
     }
     else
     {
         State            s = State.getInstance();
         CustomizeFactory f = new CustomizeFactory();
         Car    c;
         Car    config = new Car(-1);
         Engine eng    = new Engine();
         eng.EngineType   = (EEngine)CarEngine.SelectedIndex;
         config.Engine    = eng;
         config.CarType   = (ECarType)CarType.SelectedIndex;
         config.Model     = (ECarModel)CarModel.SelectedIndex;
         f.configurations = config;
         c = f.GetCar();
         CarPrice.Content        = c.Price;
         CarAccesory.ItemsSource = c.Accessories;
     }
 }
 private void Button_Click_2(object sender, RoutedEventArgs e)
 {
     if (CarModel.SelectedIndex == -1
         ||
         CarColor.SelectedIndex == -1
         ||
         CarEngine.SelectedIndex == -1
         ||
         CarType.SelectedIndex == -1
         )
     {
         return;
     }
     else
     {
         State            s = State.getInstance();
         CustomizeFactory f = new CustomizeFactory();
         Car    c;
         Car    config = new Car(-1);
         Engine eng    = new Engine();
         eng.EngineType   = (EEngine)CarEngine.SelectedIndex;
         config.Engine    = eng;
         config.CarType   = (ECarType)CarType.SelectedIndex;
         config.Model     = (ECarModel)CarModel.SelectedIndex;
         f.configurations = config;
         c = f.GetCar();
         CarPrice.Content        = c.Price;
         CarAccesory.ItemsSource = c.Accessories;
         s.d.BuyCar(c);
         s.userCarlist.Add(c);
         Switcher.Switch(new ClientMenu());
     }
 }