非常奇怪的绑定问题:命令和自定义属性

下面是我的用户控件的顶部:

<UserControl x:Class="MyApp.Common.Controls.Views.SimpleView"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             xmlns:Framework="http://www.memoryexpress.com/UIFramework"
             mc:Ignorable="d" 
             Height="130" Width="450"
             x:Name="Master"
             >
    <!-- Behaviour under the context of the generic dialog -->
    <Framework:DialogMetadata.Instance>
        <Framework:DialogMetadata SizeToContent="WidthAndHeight" 
                                  ResizeMode="NoResize" 
                                  ConfirmCommand="{Binding ConfirmCommand, RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type UserControl}}}"
                                  ConfirmButtonText="Run"/>
    </Framework:DialogMetadata.Instance>

DialogMetadata.Instance 接受类型为 DialogMetadata

这在很大程度上都是有效的,我已经把它捡起来了 SizeToContent ResizeMode ConfirmButtonText .

多功能虚拟机 当我们单击确认按钮时,我想把这个命令传递给要执行的对话框。如您所见,我试图将ViewModel的命令绑定到DialogMetadata的 confirm命令 从属属性。

DP的定义如下:

    #region DP - ConfirmCommand

    public static DependencyProperty ConfirmCommandProperty =
        DependencyProperty.Register("ConfirmCommand", typeof (IBaseCommand), typeof (DialogMetadata),
                                    new PropertyMetadata(null));

    /// <summary>
    /// The Confirmation Command for a dialog. This allows us to sync up to the user-control for 
    /// determining if we can can hit the Ok Button, and to perform additional logic
    /// </summary>
    public virtual IBaseCommand ConfirmCommand
    {
        get { return GetValue(ConfirmCommandProperty) as IBaseCommand; }
        set { SetValue(ConfirmCommandProperty, value); }
    }

    #endregion

(注意:属性'ConfirmCommand'存在于UserControl的数据上下文中,并且具有非空值。)

结合

{Binding ConfirmCommand, RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type UserControl}}}

System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.UserControl', AncestorLevel='1''. BindingExpression:Path=ConfirmCommand; DataItem=null; target element is 'DialogMetadata' (Name=''); target property is 'ConfirmCommand' (type 'IBaseCommand')

结合

{Binding ConfirmCommand, ElementName=Master}

错误

System.Windows.Data Error: 4 : Cannot find source for binding with reference 'ElementName=Master'. BindingExpression:Path=ConfirmCommand; DataItem=null; target element is 'DialogMetadata' (Name=''); target property is 'ConfirmCommand' (type 'IBaseCommand')