用于子控件的UserControl属性触发器

Question

根据我的UserControl的IsEnabled属性(true/false),我希望其中的控件具有不同的颜色.我希望用XAML的"魔力"来做到这一点.

<UserControl.Resources>
    <Style x:Key="EnableDependent" TargetType="{x:Type Shape}">
        <Style.Triggers>
            <Trigger Property="{Binding Path=IsEnabled, RelativeSource={RelativeSource AncestorType={x:Type UserControl}}}" Value="True">
                <Setter Property="Stroke" Value="White" />
            </Trigger>
            <Trigger Property="{Binding Path=IsEnabled, RelativeSource={RelativeSource AncestorType={x:Type UserControl}}}" Value="False">
                <Setter Property="Stroke" Value="Black" />
            </Trigger>
        </Style.Triggers>
    </Style>
</UserControl.Resources>

该样式应用于绘制路径的ViewBox中:

    <Viewbox  Grid.Column="3" Width="18" Margin="5,5,2,5" MouseEnter="Dispatch_MouseEnter" DockPanel.Dock="Right" Stretch="Uniform">
        <Path Data="M0,1 L4,1 M2,0 L4,1 L2,2" Stretch="Fill" StrokeThickness="3" Width="12" Height="12" Style="{StaticResource EnableDependent}" />
    </Viewbox>

我得到一个运行时异常,即无法在触发器的"Property"属性中设置绑定.

那么这样做的方法是什么？

Answer 1

使用一个DataTrigger代替正常Trigger的内部属性更改,它有一个Binding-Property,你可以在那里做.

<Style x:Key="EnableDependent" TargetType="{x:Type Shape}">
    <Style.Triggers>
        <DataTrigger Binding="{Binding Path=IsEnabled, RelativeSource={RelativeSource AncestorType={x:Type UserControl}}}" Value="True">
            <Setter Property="Stroke" Value="White" />
        </DataTrigger>
        <DataTrigger Binding="{Binding Path=IsEnabled, RelativeSource={RelativeSource AncestorType={x:Type UserControl}}}" Value="False">
            <Setter Property="Stroke" Value="Black" />
        </DataTrigger>
    </Style.Triggers>
</Style>