I am trying to create a simple (I think) animation effect based on a property change in my ViewModel. I would like the target to be a specific textblock in the control template of a custom control, which inherits from Window.

From the article examples I've seen, a DataTrigger is the easiest way to accomplish this. It appears that Window.Triggers doesn't support DataTriggers, which led me to try to apply the trigger in the style. The problem I am currently having is that I can't seem to target the TextBlock (or any other child control)--what happens is which the code below is that the animation is applied to the background of the whole window.

If I leave off StoryBoard.Target completely, the effect is exactly the same.

Is this the right approach with the wrong syntax, or is there an easier way to accomplish this?

<Style x:Key="MyWindowStyle" TargetType="{x:Type Window}">
    <Setter Property="Template" Value="{StaticResource MyWindowTemplate}"/>
    <Style.Triggers>
        <DataTrigger Binding="{Binding ChangeOccurred}" Value="True">
            <DataTrigger.EnterActions>
                <BeginStoryboard>
                    <Storyboard BeginTime="00:00:00" Duration="0:0:2" Storyboard.Target="{Binding RelativeSource={RelativeSource AncestorType=TextBlock}}"
                                    Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)">
                        <ColorAnimation FillBehavior="Stop" From="Black" To="Red" Duration="0:0:0.5" AutoReverse="True"/>
                    </Storyboard>
                </BeginStoryboard>
            </DataTrigger.EnterActions>
        </DataTrigger>
    </Style.Triggers>
</Style>