Catel ViewModelToModel 没有链接

Posted 2023-05-08

【中文标题】Catel ViewModelToModel 没有链接

【英文标题】：Catel ViewModelToModel not linking

【发布时间】：2017-06-06 09:42:08

【问题描述】：

我有一个简单的ViewModel，它有两个Models。所以它看起来像这样：

public class ConnectionItemSelectorViewModel : ViewModelBase 
    ...

    #region AvailableConnectionsModel

    // Model Nr. 1
    [Model]
    public ConnectionList AvailableConnectionsModel
    
        get  return GetValue<ConnectionList>(AvailableConnectionsModelProperty); 
        set  SetValue(AvailableConnectionsModelProperty, value); 
    

    public static readonly PropertyData AvailableConnectionsModelProperty = RegisterProperty(nameof(AvailableConnectionsModel), typeof(ConnectionList), () => new ConnectionList());

    #endregion

    #region SelectedConnectionsModel

    // Model Nr. 2
    [Model]
    public ConnectionList SelectedConnectionsModel
    
        get  return GetValue<ConnectionList>(SelectedConnectionsModelProperty); 
        set  SetValue(SelectedConnectionsModelProperty, value); 
    

    public static readonly PropertyData SelectedConnectionsModelProperty = RegisterProperty(nameof(SelectedConnectionsModel), typeof(ConnectionList), () => new ConnectionList());

    #endregion

    ...

ConnectionList 扩展了ModelBase，所以我可以多次使用[Model]-属性。

现在我想将 Model 的属性暴露给 ViewModel：

public class ConnectionItemSelectorViewModel : ViewModelBase 
    ...
    // init Model properties

    #region AvailableConnections

    // Using a unique name for the property in the ViewModel
    // but linking to the "correct" property in the Model by its name
    [ViewModelToModel(nameof(AvailableConnectionsModel), nameof(ConnectionList.Connections))]
    public ObservableCollection<ConnectionItem> AvailableConnections
    
        get  return GetValue<ObservableCollection<ConnectionItem>>(AvailableConnectionsProperty); 
        set  SetValue(AvailableConnectionsProperty, value); 
    

    public static readonly PropertyData AvailableConnectionsProperty = RegisterProperty(nameof(AvailableConnections), typeof(ObservableCollection<ConnectionItem>), () => null);

    #endregion

    // linking other properties to the models
    ...

问题是链接不起作用。所以在初始化之后，属性AvailableConnections（以及其他属性）仍然是null，尽管模型本身已正确初始化。

是我遗漏了什么还是根本不可能？

提前谢谢！

【参考方案1】：

尝试在 ViewModelToModel 属性上设置MappingType，以便模型获胜。

【讨论】：

谢谢！设置Mode = ViewModelToModelMode.Explicit 有效！