I figured it out, Triggers must be used instead of DataTriggers:
<GridSplitter.Style>
<Style TargetType="{x:Type GridSplitter}">
<Setter Property="Background" Value="Transparent"/>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="AliceBlue"/>
</Trigger>
</Style.Triggers>
</Style>
</GridSplitter.Style>
By the way, I think that if I set the Visibility
to Hidden
I can't target the GridSplitter
, so I switch its Background
instead.