Add Columnheader to Treeview with HierarchicalDataTemplate - wpf

Question

I want do add a Columnheader to a Treeview (see below). However, if I add a row to the ControlTempalte for the TreeViewItem, the Header is shown above each item. How can I add a Headerrow, that just shows once above the whole tree?
I want to show a ColumnHeader like in a DataGrid as shown (white on grey text) in the picture below:
<TreeView Grid.Row="1" ItemsSource="{Binding AktuellerDatensatz.Abschnitte}"
SelectedItemChanged="TreeView_SelectedItemChanged" Style="{StaticResource StandardTreeview}">
<TreeView.ItemTemplate>
<HierarchicalDataTemplate DataType="{x:Type model:BaustelleModel}" ItemsSource="{Binding Abschnitte}">
<DockPanel HorizontalAlignment="Stretch" >
<Grid HorizontalAlignment="Stretch" >
<Grid.ColumnDefinitions>
<ColumnDefinition Width="{Binding Converter={StaticResource Breite}}"/>
<ColumnDefinition Width="100"/>
<ColumnDefinition Width="100"/>
<ColumnDefinition Width="50"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Border Grid.Column="0" BorderThickness="0 0 1 1" BorderBrush="{StaticResource Grau}">
<Label Content="{Binding Name}"/>
</Border>
<Border Grid.Column="1" BorderThickness="0 0 1 1" BorderBrush="{StaticResource Grau}">
<Label Content="{Binding Start}" />
</Border>
<Border Grid.Column="2" BorderThickness="0 0 1 1" BorderBrush="{StaticResource Grau}">
<Label Content="{Binding End}" Grid.Column="2" />
</Border>
<Border Grid.Column="3" BorderThickness="0 0 1 1" BorderBrush="{StaticResource Grau}">
<Label Content="{Binding Duration}" />
</Border>
<Border Grid.Column="4" BorderThickness="0 0 1 1" BorderBrush="{StaticResource Grau}">
<Label />
</Border>
</Grid>
</DockPanel>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView>

Answer 1

The best way to achieve the requirement is to include TreeView inside DataGrid instead of doing it reverse. You can refer here
With TreeView, you can try using AlternationIndex to show the headers only for the first item in every level.
<Grid.Style>
<Style TargetType="Grid">
<Setter Property="Visibility" Value="Collapsed"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=(ItemsControl.AlternationIndex), RelativeSource={RelativeSource AncestorType=TreeViewItem, Mode=FindAncestor}}" Value="0">
<Setter Property="Visibility" Value="Visible"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Grid.Style>
Remember to set AlternationCount to max int value for your TreeView.