如何使用 Caliburn.Micro MVVM 从 WPF 中同一视图上的另一个视图模型更新列表

Question

我是 WPF 新手，我想使用 Caliburn Micro 遵循 MVVM 框架。我无法从另一个视图模型中更新视图模型中的列表。

我有3个观点：

• POSView ：包含另外 2 个视图的两个内容控件

• 产品视图：所有产品的列表

• CartView ：购物车中添加的所有产品的列表

单击产品视图中的产品后，产品应添加到购物车视图中

POSViewModel.cs

public class POSViewModel : Conductor<object>.Collection.AllActive

    {

        #region Private Variables

        private ProductsViewModel _ProductsViewModel;

        private CartViewModel _CartViewModel;

        #endregion

        #region Public Variables

        public ProductsViewModel ProductsViewModel

        {

            get { return _ProductsViewModel; }

            set { _ProductsViewModel = value; }

        }

        public CartViewModel CartViewModel

        {

            get { return _CartViewModel; }

            set { _CartViewModel = value; }

        }

        #endregion

        #region Public Methods

        public POSViewModel()

        {

            ProductsViewModel = new ProductsViewModel();

            CartViewModel = new CartViewModel();

        }

        #endregion

    }

ProductsViewModel.cs：在 AddProdClick(ProductModel ProductModel) 上，我想将单击的产品添加到 CartView。

public class ProductsViewModel : Conductor<object>

    {

        public BindableCollection<ProductModel> Products { get; set; }

        public ProductsViewModel()

        {

            Products = new BindableCollection<ProductModel>();

            for (int i = 0; i < 25; i++)

            {

                Products.Add(new ProductModel

                {

                    ProductName = "Product" + i.ToString(),

                    Qty = i + 2,

                    Rate = i * 10

                }); ;

            }

        }

        public void AddProdClick(ProductModel productModel)

        {

        }

    }

我希望将商品添加到购物车。

Answer 1

您可以使用 CartViewModel 作为参数：&nbsp; &nbsp; public POSViewModel()&nbsp; &nbsp; {&nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; CartViewModel = new CartViewModel();&nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; ProductsViewModel = new ProductsViewModel(CartViewModel);&nbsp; &nbsp; }并在 ProductsViewModel 的构造函数中使用它public class ProductsViewModel : Conductor<object>{&nbsp; &nbsp; public BindableCollection<ProductModel> Products { get; set; }&nbsp; &nbsp; public CartViewModel CVM { get; set; }&nbsp; &nbsp; public ProductsViewModel(CartViewModel CVM)&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; this.CVM = CVM;&nbsp; &nbsp; }&nbsp; &nbsp; public void AddProdClick(ProductModel productModel)&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CVM.Add(productModel)&nbsp; &nbsp; }}您还有另一个解决方案：使用 PosViewModel：&nbsp;public POSViewModel(){&nbsp; &nbsp;&nbsp; &nbsp; CartViewModel = new CartViewModel();&nbsp; &nbsp;&nbsp;&nbsp; &nbsp; ProductsViewModel = new ProductsViewModel(this);}public class ProductsViewModel : Conductor<object>{&nbsp; &nbsp; public BindableCollection<ProductModel> Products { get; set; }&nbsp; &nbsp; public CartViewModel CVM { get; set; }&nbsp; &nbsp; public ProductsViewModel(POSViewModel PVM)&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; this.CVM = PVM.CartViewModel;&nbsp; &nbsp; }&nbsp; &nbsp; public void AddProdClick(ProductModel productModel)&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; CVM.Add(productModel)&nbsp; &nbsp; }}第三种解决方案是使用EventAggregator，您需要修改一些编码请参阅事件聚合器单击时，您在 Add 方法中执行 EventAggregator.publish(new Addevent)在 PosviewModel 中你可以捕捉到事件......但为此你必须修改一些代码行，但阅读链接并不复杂