WPF toolbar's style not working - wpf

Question

I'm using a resource dictionary in my wpf proyect.
The dictionary has these 2 styles:
<Style x:Key="MyMenu" TargetType="Menu">
<Setter Property="Background" Value="Black"/>
<Setter Property="Foreground" Value="White"/>
</Style>
<Style x:Key="MyToolbar" TargetType="ToolBar">
<Setter Property="Background" Value="Black"/>
</Style>
And in my XAML file, I use these 2 styles as it follows:
For the menu:
<Menu Name="menuMainBar" Style="{DynamicResource MyMenu}" IsMainMenu="True" VerticalAlignment="Top" Margin="0,10,0,0">
<MenuItem ...
</Menu>
For the toolbar:
<ToolBarTray Name="toolBarTrayRigth_wargames" Orientation="Vertical" HorizontalAlignment="Left" VerticalAlignment="Top" Width="50">
<ToolBar Name="toolBarRigth_wargames" Style="{StaticResource MyToolbar}" BorderThickness="0,0,1,0">
<Button ...
</ToolBar>
</ToolBarTray>
This is the result:
As you can notice, the menu takes the style correctly, but the toolbar isn't affected by the style at all.
I tried removing all the style elements from the toolbartray tag, as it follows:
<ToolBarTray Name="toolBarTrayRigth_wargames">
...
</ToolBarTray>
And now the toolbar works, but as you can see, now the toolbarTray is not how I want it to be (I want a vertical toolbar, not a horizontal toolbar):
I also tried setting the background of the ToolBar directly in the xaml file:
<ToolBarTray Name="toolBarTrayRigth_wargames" Orientation="Vertical" HorizontalAlignment="Left" VerticalAlignment="Top" Width="50">
<ToolBar Name="toolBarRigth_wargames" BorderThickness="0,0,1,0" Background="Black">
<Button ...
</ToolBar>
</ToolBarTray>
...and it works:
But I don't want to do that, I want to use a resource dictionary for my toolbar's style.
any ideas on how to achieve that?

Answer 1

I found, bizarrely, that if I set the Orientation of the parent ToolBarTray to Horizontal, that your ToolBar style was able to set the background on the ToolBar.
I also found that with the ToolBarTray orientation still being Vertical, this worked to set the ToolBar's background:
<Style x:Key="MyToolbar" TargetType="ToolBar">
<Style.Triggers>
<!--
This is intentional. A conventional setter was found not to set the background
when the parent ToolBarTray's Orientation was Vertical.
-->
<DataTrigger Binding="{Binding Source={x:Null}}" Value="{x:Null}">
<Setter Property="Background" Value="Black" />
</DataTrigger>
</Style.Triggers>
</Style>
I find this very strange.

Answer 2

as #EdPlunkett found, its a strange Setter in the default template in the Trigger for Vertical Orientation:
<Trigger Property="Orientation" Value="Vertical">
<Setter Property="Margin" TargetName="Grid" Value="1,3,1,1"/>
<Setter Property="Style" TargetName="OverflowButton">
<Setter.Value>
<Style TargetType="{x:Type ToggleButton}">
<Setter Property="Background" Value="#FFEEF5FD"/>
you can edit the template (in Document Outline panel, right click on the ToolBar element > Edit Template > Edit a Copy...), and remove this Setter.