如何拉伸HeaderedContentControl的内容？

Question

我有一个包含TreeView的HeaderedContentControl.

    <HeaderedContentControl Header="Steps" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
        <TreeView Name="WizardSteps" ItemsSource="{Binding WizardSteps}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
            <!-- Hierarchical data templates here -->
        </TreeView>
    </HeaderedContentControl>

虽然HeaderedContentControl伸展以填充其父网格内的区域,但我的TreeView控件仅占用可用空间的一小部分.

如何扩展我的TreeView以填充HeaderedContentControl的内容区域？

Answer 1

默认控件模板HeaderedContentControl是这样的:

<ControlTemplate TargetType="{x:Type HeaderedContentControl}">
    <StackPanel>
        <ContentPresenter ContentSource="Header" />
        <ContentPresenter />
    </StackPanel>
</ControlTemplate>

StackPanel让每个孩子都有自己想要的高度,因此TreeView不会伸展.您可以将其替换为使用DockPanel的模板:

<HeaderedContentControl Header="Steps" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" VerticalContentAlignment="Stretch" >
    <HeaderedContentControl.Template>
        <ControlTemplate TargetType="HeaderedContentControl">
            <DockPanel>
                <ContentPresenter DockPanel.Dock="Top" ContentSource="Header" />
                <ContentPresenter />
            </DockPanel>
        </ControlTemplate>
    </HeaderedContentControl.Template>

如果要使其更具可重用性,请在样式中设置模板并使用VerticalContentAlignment:

<Style TargetType="HeaderedContentControl">
    <Setter Property="VerticalContentAlignment" Value="Stretch"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="HeaderedContentControl">
                <DockPanel>
                    <ContentPresenter DockPanel.Dock="Top" ContentSource="Header" />
                    <ContentPresenter VerticalAlignment="{TemplateBinding VerticalContentAlignment}" />
                </DockPanel>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

这样,默认情况下,所有HeaderedContentControl都将填充其内容,您可以通过在单个控件上设置VerticalContentAlignment来覆盖它.

或者,您可以直接使用DockPanel而不是HeaderedContentControl.