private void Product_EditClickedEventHandler(object sender, RoutedEventArgs e)
        {
            RegisteredProduct product         = ProductDataGrid.SelectedItem as RegisteredProduct;
            Product_AddEdit   editProductForm = new Product_AddEdit(Ctx, RegisteredProducts, product);

            editProductForm.Show();
        }
        private void Product_AddClickedEventHandler(object sender, RoutedEventArgs e)
        {
            Product_AddEdit addProductForm = new Product_AddEdit(Ctx, RegisteredProducts);

            addProductForm.Show();
        }