public async Task InitializeAsync() { if (_isInitialized) { return; } PizzaMenuItems.AddRange(await _restaurant.GetMenuItemsAsync()); var defaultDeliveryAddress = await _restaurant.GetDefaultDeliveryAddressAsync(); if (defaultDeliveryAddress != null) { Order.DeliveryAddress.StreetAddress = defaultDeliveryAddress.StreetAddress; Order.DeliveryAddress.City = defaultDeliveryAddress.City; Order.DeliveryAddress.Zip = defaultDeliveryAddress.Zip; } _isInitialized = true; }