ChangePropertyAction in ItemsControl

[hailstorm75]

Hello!
I'm creating a configuration page consisting of multiple steps.
These steps are displayed via MVVM in an ItemsControl and the active step should be visually highlighted.

Unfortunately, I'm unable to achieve this using Avalonia Behaviors.

Here is a simplified snippet of my view:

      <ItemsControl Items="{Binding Steps}">
        <ItemsControl.ItemTemplate>
          <DataTemplate DataType="{x:Type core:IPluginStep}">
            <Label
              BorderBrush="Blue"
              Margin="5"
              Content="{Binding Name}"
              Padding="5,0,0,0">
              <Interaction.Behaviors>
                <DataTriggerBehavior
                  Binding="{Binding Id}"
                  ComparisonCondition="Equal"
                  Value="{Binding DataContext.CurrentStep.Id, ElementName=Root}">
                  <ChangePropertyAction
                    PropertyName="BorderThickness"
                    TargetObject="{Binding Path., RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Label}}"
                    Value="10" />
                </DataTriggerBehavior>
                <DataTriggerBehavior
                  Binding="{Binding Id}"
                  ComparisonCondition="NotEqual"
                  Value="{Binding DataContext.CurrentStep.Id, ElementName=Root}">
                  <ChangePropertyAction
                    PropertyName="BorderThickness"
                    TargetObject="{Binding Path., RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Label}}"
                    Value="0" />
                </DataTriggerBehavior>
              </Interaction.Behaviors>
            </Label>
          </DataTemplate>
        </ItemsControl.ItemTemplate>
      </ItemsControl>

Complete implementation

Could you please let me know what I'm doing wrong?

• I've double checked the compared values,
• I've tried naming the label and referencing it in the TargetObject via the hashtag,
• I've tried without the TargetObject tag entirely

Thank you!