Question

如果在视图模型中发生某些事情，我想在视图中执行某些代码。我已经研究了 Prism事件聚合器但是我没有成功使用棱镜5.如果有更简单的方法这样做会有所帮助。任何关于此的博客或相同代码也将起作用

Answer 1

正如Ed Plunkett所说，要做的就是在视图中监听DataContextChanged，因为这就是View与ViewModels连接的方式。

以下是一个例子：

public partial class MyView : UserControl
{
    public MyView ()
    {
        DataContextChanged += MyView_DataContextChanged;
    }

    private void MyView_DataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
    {
        //new ViewModel has been set.
        MyViewModel myViewModel = e.NewValue as MyViewModel;
        if (myViewModel != null)
        {
            //check for property changes
            myViewModel.PropertyChanged += MyViewModel_PropertyChanged;

            //custom event for specific update
            myViewModel.MyCustomEventTriggered += MyViewModel_MyCustomEventTriggered
        }
    }

    private void MyViewModel_PropertyChanged(object sender, PropertyChangedEventArgs e)
    {
        //do your logic
    }

    private void MyViewModel_MyCustomEventTriggered(object sender, MyCustomEventArgs e)
    {
        //do your logic
    }
}

如何在WPF中从视图模型到MVVM中的视图进行通信

1 个答案: