wpf - 绑定到祖先 StackPanel DockPanel.Dock

Question

我有一个 StackPanel，可以停靠在 DockPanel 的左侧或右侧。StackPanel 中的项目应该像祖先一样停靠在同一侧。对于测试，我在 Visual Tree 中获得了祖先的名称，但我不知道如何绑定到 Docking.Dock。提前致谢。

<DockPanel>
  <StackPanel x:Name="RightHandContainer" DockPanel.Dock="Right">
    <v:MyUsercontrol TextCaption="Hard-Coded Alignment Works" Alignment="Right" />
    <v:MyUsercontrol TextCaption="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=StackPanel, AncestorLevel=1}, Path=Name}"                  
                       Alignment="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=StackPanel, AncestorLevel=1}, Path=Docking.Dock}" />
    <!-- TextCaption is is a dependencyproperty of Type string, works fine ... my Text object automatically gets 'RightHandContainer' -->
    <!-- Alignment is is a dependencyproperty of Type Dock, like Docking.Dock ... Binding will not work :( -->
  </StackPanel>
</DockPanel>

Answer 1

一种方法是创建一个价值转换器。将属性绑定到 stackpanel 本身，然后在 valueconverter 中抓取停靠栏并返回您需要的任何内容。像这样的东西：

<Window.Resources>
    <app:TestConverter x:Key="TestConverter" />
</Window.Resources>
<DockPanel>
    <StackPanel x:Name="RightHandContainer" DockPanel.Dock="Right">
        <TextBlock Text="Test" HorizontalAlignment="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=StackPanel, AncestorLevel=1}, Converter={StaticResource TestConverter}}"  />
    </StackPanel>
</DockPanel>

转换器：

public class TestConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        HorizontalAlignment alignment = HorizontalAlignment.Left;

        StackPanel stackPanel = value as StackPanel;
        if (stackPanel != null)
        {
            Dock dock = DockPanel.GetDock(stackPanel);
            switch (dock)
            {
                case Dock.Left: alignment = HorizontalAlignment.Left; break;
                case Dock.Right: alignment = HorizontalAlignment.Right; break;
            }
        }   
        return alignment;
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

我使用了水平对齐，但你可以返回任何你需要的东西。