我对WPF treeviewitem有问题

Question

Below treeview xaml file :

<TreeView Name="templatetree"
          SelectedItemChanged="templatetree_SelectedItemChanged"
          MaxHeight="210" Background="{StaticResource MediumGrayBrush}"
          ScrollViewer.VerticalScrollBarVisibility="Auto"
          ScrollViewer.HorizontalScrollBarVisibility="Auto">
    <TreeView.ItemContainerStyle>
        <Style TargetType="{x:Type TreeViewItem}">
            <Setter Property="IsExpanded" Value="True"/>
            <Setter Property="IsSelected" Value="False" />
        </Style>
    </TreeView.ItemContainerStyle>
    <TreeView.Resources>
        <SolidColorBrush x:Key="{x:Static SystemColors.InactiveSelectionHighlightBrushKey}"
                         Color="#FF1E90FF"/>

        <HierarchicalDataTemplate DataType="{x:Type Tree:Templates}" ItemsSource="{Binding Members}">
            <StackPanel Orientation="Horizontal">
                <Image Source="../Images/template.png"
                       Height="22" Width="22" Margin="0,0,5,0"/>
                <TextBlock Text="{Binding Name}"
                           Style="{StaticResource PopupBodyTextStyle}"
                           FontFamily="{StaticResource Symbol}" MouseLeftButtonDown="HeaderNode_MouseLeftButtonDown"/>
                <TextBlock Text=" [" Foreground="{StaticResource HighlightBrush}"/>
                <TextBlock Text="{Binding Members.Count}" Foreground="{StaticResource HighlightBrush}"/>
                <TextBlock Text="]" Foreground="{StaticResource HighlightBrush}"/>
            </StackPanel>
        </HierarchicalDataTemplate>
        <DataTemplate DataType="{x:Type Tree:TemplateTypes}">
            <StackPanel Orientation="Horizontal">
                <TextBlock Text="{Binding Name}"
                           Style="{StaticResource PopupBodyTextStyle}"
                           FontFamily="{StaticResource Symbol}"
                           MouseLeftButtonDown="MemberNode_MouseLeftButtonDown"/>
            </StackPanel>
        </DataTemplate>
    </TreeView.Resources>
</TreeView>

Class file like below:

public class Templates
{
    public string Name { get; set; } 

    public ObservableCollection<TemplateTypes> Members { get; set; } = new ObservableCollection<TemplateTypes>();
}

public class TemplateTypes
{
    public string Name { get; set; }

    public string Version { get; set; }
}

Output like :

Template1
    --Template1.1    
    --Template1.2

Template2
    --Template2.1

I want set IsSelected property of TreeViewItem for child node(Template1.1) through programatically but it gives me only for parent node (Template1)

I tried to get item from treeview but it gives parent node only

{
.
.
.
.

templatetree.ItemsSource = nodeList;
}

TreeViewItem tr = (TreeViewItem)templatetree.ItemContainerGenerator.ContainerFromItem(templatetree.Items[0]);\\This lines gives me parent node of Template Type.

How can I set IsSelected property for child node?

expected result : Child item selection

Answer 1

To add style for second level you need to set it in HierarchicalDataTemplate like this

<HierarchicalDataTemplate DataType="{x:Type Tree:Templates}" ItemsSource="{Binding Members}">
    <StackPanel Orientation="Horizontal">
        <Image Source="../Images/template.png"
                   Height="22" Width="22" Margin="0,0,5,0"/>
        <TextBlock Text="{Binding Name}"
                       Style="{StaticResource PopupBodyTextStyle}"
                       FontFamily="{StaticResource Symbol}" MouseLeftButtonDown="HeaderNode_MouseLeftButtonDown"/>
        <TextBlock Text=" [" Foreground="{StaticResource HighlightBrush}"/>
        <TextBlock Text="{Binding Members.Count}" Foreground="{StaticResource HighlightBrush}"/>
        <TextBlock Text="]" Foreground="{StaticResource HighlightBrush}"/>
    </StackPanel>
    <HierarchicalDataTemplate.ItemContainerStyle>
        <Style TargetType="TreeViewItem">
            <Setter Property="IsSelected" Value="False" />
        </Style>
    </HierarchicalDataTemplate.ItemContainerStyle>
</HierarchicalDataTemplate>

Below is an example of style multi level TreeViewItem

    <DataTemplate x:Key="MenuItemTemplate" >
       <TreeViewItem/>
    </DataTemplate>
    <HierarchicalDataTemplate x:Key="ThirdLevel" ItemTemplate="{StaticResource MenuItemTemplate}">
       <TextBlock Text="Text" />
       <HierarchicalDataTemplate.ItemContainerStyle>
          <Style>
          <!--  3rd STYLE HERE  -->
          </Style>
       </HierarchicalDataTemplate.ItemContainerStyle>
     </HierarchicalDataTemplate>

     <HierarchicalDataTemplate x:Key="SecondLevel" ItemTemplate="{StaticResource ThirdLevel}">
        <TextBlock Text="Text" />
        <HierarchicalDataTemplate.ItemContainerStyle>
           <Style>
               <!--  2nd STYLE HERE  -->
           </Style>
        </HierarchicalDataTemplate.ItemContainerStyle>
      </HierarchicalDataTemplate>

     <TreeView ItemTemplate="{StaticResource SecondLevel}">
         <TreeView.ItemContainerStyle>
         <Style>
             <!--  1st Level Style  -->
          </Style>
         </TreeView.ItemContainerStyle>
     </TreeView>