WPF-MvvmLight NotificationMessageWithCallback示例？

Question

某處是否存在名爲NotificationMessageWithCallback的MvvmLight功能的WPF示例？

我只想問一個簡單的刪除確認對話框。

感謝

Answer 1

要從視圖模型的值傳遞到視圖，首先創建一個自定義Message 與相關屬性。我們從NotificationMessageAction<MessageBoxResult>繼承你提到你想要一個確認框

public class MyMessage : NotificationMessageAction<MessageBoxResult> 
{ 
    public string MyProperty { get; set; } 

    public MyMessage(object sender, string notification, Action<MessageBoxResult> callback) : 
     base (sender, notification, callback) 
    { 
    } 
} 

在我們的視圖模型我的命令發送新MyMessage被擊中（SomeCommand）

public class MyViewModel : ViewModelBase 
{ 
    public RelayCommand SomeCommand 
    { 
      get 
      { 
       return new RelayCommand(() => 
       { 
        var msg = new MyMessage(this, "Delete", (result) => 
          { 
           //result holds the users input from delete dialog box 
           if (result == MessageBoxResult.Ok) 
           { 
            //delete from viewmodel 
           } 
          }) { MyProperty = "some value to pass to view" }; 

        //send the message 
        Messenger.Default.Send(msg);   
             } 
       }); 
      } 
    } 
} 

最後，我們需要在註冊的消息後面的視圖代碼

public partial class MainWindow : Window 
{ 
    private string myOtherProperty; 

    public MainWindow() 
    { 
      InitializeComponent(); 

      Messenger.Default.Register<MyMessage>(this, (msg) => 
      { 
       myOtherProperty = msg.MyProperty; 
       var result = MessageBox.Show("Are you sure you want to delete?", "Delete", MessageBoxButton.OKCancel); 
       msg.Execute(result); 
      }