private void AddCategoryClick(object sender, RoutedEventArgs e)
        {
            MenuItemEditor win = new MenuItemEditor();

            if (win.ShowDialog() == true)
            {
                win.Category.CategoryId = this.catRepo.Insert(DataConverter.CategoryConverter(win.Category));

                this.avm.CategoryList.Add(win.Category);
                this.categoryListBox.Items.Refresh();

                // MessageBox.Show("Sikeres hozzáadás!");
            }
        }
        private void EditCategoryClick(object sender, RoutedEventArgs e)
        {
            Window win = new MenuItemEditor(this.avm.SelectedCategory);

            if (this.avm.SelectedCategory != null)
            {
                if (win.ShowDialog() == true)
                {
                    this.catRepo.Update(DataConverter.CategoryConverter(this.avm.SelectedCategory));

                    this.categoryListBox.Items.Refresh();
                    MessageBox.Show("Sikeres módosítás!");
                }
            }
        }
        private void EditProductClick(object sender, RoutedEventArgs e)
        {
            MenuItemEditor win = new MenuItemEditor(this.avm.SelectedProduct);

            if (this.avm.SelectedProduct != null)
            {
                if (win.ShowDialog() == true)
                {
                    this.productRepo.Update(this.converter.ProductConverter(this.avm.SelectedProduct));

                    this.productListBox.Items.Refresh();
                    MessageBox.Show("Sikeres módosítás!");
                }
            }
        }
        private void AddProductClick(object sender, RoutedEventArgs e)
        {
            MenuItemEditor win = new MenuItemEditor(true);

            if (win.ShowDialog() == true)
            {
                win.Product.Category = this.avm.SelectedCategory;

                win.Product.TermekId = this.productRepo.Insert(this.converter.ProductConverter(win.Product));

                this.avm.FilteredProducts.Add(win.Product);
                this.avm.ProductList.Add(win.Product);
                this.productListBox.Items.Refresh();

                // MessageBox.Show("Sikeres hozzáadás!");
            }
        }