How to remove ContextMenu border

Question

So im trying to make button appear on right click in my ListBox .

<ListBox Grid.Column="1" Margin="358,44,20,63" Name="scriptbox" Background="#FF282828" Foreground="White" SelectionChanged="Scriptbox_SelectionChanged" BorderThickness="0">
   <ListBox.ContextMenu>
      <ContextMenu>
         <MenuItem
            Template="{DynamicResource MenuItemTemplate}"
            Header="Delete" 
            Click="MenuItemDelete_Click" >
         </MenuItem>
      </ContextMenu>
   </ListBox.ContextMenu>

This is my MenuItem template.

<ControlTemplate TargetType="{x:Type MenuItem}" x:Key="MenuItemTemplate">
   <Border x:Name="Border" Background="#FF282828"  Padding="30,5,30,5" BorderThickness="0" Margin="0">
      <ContentPresenter ContentSource="Header" x:Name="HeaderHost" RecognizesAccessKey="True" />
   </Border>
   <ControlTemplate.Triggers>
      <Trigger Property="IsHighlighted" Value="true">
         <Setter Property="Background" TargetName="Border" Value="#51544e"/>
      </Trigger>
   </ControlTemplate.Triggers>
</ControlTemplate>
<ItemsPanelTemplate x:Key="MenuItemPanelTemplate">
   <StackPanel Margin="-3,0,0,0" Background="White"/>
</ItemsPanelTemplate>
<Style TargetType="{x:Type MenuItem}">
   <Setter Property="ItemsPanel" Value="{StaticResource MenuItemPanelTemplate}"/>
</Style>

Everything is fine but there is white border all around the button.

Answer 1

What you recognize as a white border is the ContextMenu itself that contains your MenuItem s. Try adding more buttons and changing the Background and BorderBrush of the ContextMenu and you will see.

<ContextMenu Background="Red" BorderBrush="Blue">

Changing the brushes like this will lead to this result, which makes it obvious.

If you create a custom control template for your MenuItems you should probably do so for the ContextMenu , too, if only setting brushes does not fit your requirements. As you can see in the example, there is still a vertical white line that is part of the default control template, that you might want to get rid of. You can start from this example , although it is neither the default template nor complete. Look at this related post for guidance on how to extract the default control template for ContextMenu if you need it.