在TreeView上使用ItemTemplate时如何绑定样式中的IsSelected

Question

I'm attempting to make a TreeView which uses an ItemTemplate , and also is bound to a view model which has a IsSelected property.

I'm not exactly sure why this isn't working, so I apologize if the question seems vague.

I've also reduced the code to what I think is the problem, as my app has a lot more XAML , so I hope what I've included is sufficient.

Here's how I define my DataTemplate:

    <DataTemplate x:Key="ElementDataTemplate">
        <Label Content="{Binding Path=DisplayText}"></Label>
    </DataTemplate>

Here's how I use it:

     <TreeView ItemsSource="{Binding Elements}" 
               ItemTemplate="{DynamicResource ElementDataTemplate}">
               <TreeView.Resources>
                   <Style TargetType="ListBoxItem">
                      <Setter Property="IsSelected"
                              Value="{Binding Path=IsSelected, Mode=TwoWay}" />
                      </Style>
                </TreeView.Resources>
      </TreeView>

My ViewModel has DisplayText and IsSelected properties.

I know that I'm binding correctly to the ViewModel because I am seeing the same number of items as in my Elements property of my data context, and my Label's Coutent is properly being set to DisplayText- I've verified this through breakpoints on the getter and visually when I run the app.

However, the IsSelected property's getter on the ViewModel never gets called (never hits a breakpoint), so it's clear I've messed up something on the binding of the IsSelected property.

I should point out that when I run the application I can select items with the mouse and they reflect the selection visually, so the TreeView item itself is getting selected, it's just not binding to the ViewModel's IsSelected property. Any help would be much appreciated!

Answer 1

Ahh, I'm foolish! I spent forever trying to figure out what it was, came here after a few hours, then finally figured it out:

  <TreeView.ItemContainerStyle>
      <Style TargetType="TreeViewItem">
          <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}"/>
      </Style>
  </TreeView.ItemContainerStyle>

I was using "ListBoxItem" instead of "TreeViewItem". Copy/paste got the best of me.