在 WPF 中，如何右键单击光标下的树视图项? [英] In WPF, how do I select the treeview item under my cursor on right-click?

问题描述

在 WPF 中，当我右键单击树视图项时，我希望在显示上下文菜单之前选择/激活它.

In WPF, when I right-click on a treeview item I would like it to be Selected/Activated before showing the context menu.

这听起来很简单，但是包含 hierachicalDataTemplate 会使事情变得有点复杂.

This sounds pretty simple, but the inclusion of a hierachicalDataTemplate complicates things a little.

我有以下树视图:

<TreeView 
            x:Name="trv"
            ContextMenu="{StaticResource contextMenu}"
            ItemTemplate="{StaticResource treeHierarchicalDataTemplate}"
            ItemsSource="{Binding Source={StaticResource meetingItems}}" >

            <TreeView.ItemContainerStyle>
                <Style TargetType="{x:Type TreeViewItem}">
                    <EventSetter Event="TreeViewItem.PreviewMouseRightButtonDown" Handler="trv_PreviewMouseRightButtonDown"/>
                    <Setter Property="IsExpanded" Value="True"></Setter>
                </Style>
            </TreeView.ItemContainerStyle>
        </TreeView>

这是我的事件处理程序...

And here is my event handler...

private void trv_PreviewMouseRightButtonDown(object sender, MouseButtonEventArgs e)
{
    TreeViewItem item = sender as TreeViewItem;
    if (item != null)
    {
        item.Focus();
        e.Handled = true;
    }

}

注意我是如何在上面添加一个 EventSetter 的.这几乎有效.但它只选择根级树视图节点(即我右键单击的节点的根父节点).这可能是因为我的分层数据模板?此模板可以包含相同类型的子项.

Note how I add an EventSetter above. This ALMOST works. But it only selects the root-level treeview node (i.e. the root parent of the node on which I right click). This may be because of my hierarchical data template? This template can contain children OF THE SAME TYPE.

这是我的分层数据模板...

Here is my hierarchical data template...

<HierarchicalDataTemplate x:Key="treeHierarchicalDataTemplate" 
                          ItemsSource="{Binding Path=ChildMeetingItems}">
    <HierarchicalDataTemplate.Triggers>
        <DataTrigger Binding="{Binding Path=Red}" Value="True">
            <Setter TargetName="img" Property="Image.Source" Value="pack://siteoforigin:,,,/images/bookRed.png"></Setter>
        </DataTrigger>
    </HierarchicalDataTemplate.Triggers>
    <StackPanel 
        x:Name="treeViewItemPanel"
        Background="Transparent"
        Orientation="Horizontal">
        <Image Width="16" Height="16"  x:Name="img" Margin="0,0,4,0" Source="pack://siteoforigin:,,,/images/bookGreen.png"></Image>
        <TextBlock Foreground="DarkGray" Text="{Binding DisplayIndex}" Margin="0,0,5,0"></TextBlock>
        <TextBlock Text="{Binding Summary}"></TextBlock>
    </StackPanel>
</HierarchicalDataTemplate>

知道为什么当我右键单击时只选择根节点而不是子节点吗?

Any idea on why only the root node instead of child nodes are selected when I right-click?

推荐答案

那是因为 ItemContainerStyle 没有被子节点继承.您需要在您的 HierarchicalDataTemplate 的 ItemContainerStyle 上添加相同的 EventSetter.

That's because the ItemContainerStyle is not inherited by the child nodes. You need to add the same EventSetter on the ItemContainerStyle o your HierarchicalDataTemplate.

<HierarchicalDataTemplate x:Key="treeHierarchicalDataTemplate" 
                          ItemsSource="{Binding Path=ChildMeetingItems}">
    <HierarchicalDataTemplate.Triggers>
        <DataTrigger Binding="{Binding Path=Red}" Value="True">
            <Setter TargetName="img" Property="Image.Source" Value="pack://siteoforigin:,,,/images/bookRed.png"></Setter>
        </DataTrigger>
    </HierarchicalDataTemplate.Triggers>
    <StackPanel 
        x:Name="treeViewItemPanel"
        Background="Transparent"
        Orientation="Horizontal">
        <Image Width="16" Height="16"  x:Name="img" Margin="0,0,4,0" Source="pack://siteoforigin:,,,/images/bookGreen.png"></Image>
        <TextBlock Foreground="DarkGray" Text="{Binding DisplayIndex}" Margin="0,0,5,0"></TextBlock>
        <TextBlock Text="{Binding Summary}"></TextBlock>
    </StackPanel>

<HierarchicalDataTemplate.ItemContainerStyle>
                <Style TargetType="{x:Type TreeViewItem}">
                    <EventSetter Event="TreeViewItem.PreviewMouseRightButtonDown" Handler="trv_PreviewMouseRightButtonDown"/>                    
                </Style>
            </HierarchicalDataTemplate.ItemContainerStyle>
</HierarchicalDataTemplate>

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