WPF GroupBox ContextMenu not showing unless the border/header clicked

Question

I've got a scenario where I have a GroupBox which has a bit of content in it. I'm looking to add a ContextMenu to that GroupBox and have that menu shown when the user right-clicks anywhere in the box.

The problem I have is that the context menu only appears when the border or the header of the GroupBox is clicked. If you click somewhere inside the box then the ContextMenu of the parent is what's displayed.

Here's some XAML that demonstrates the problem:

<Window x:Class="Dummy.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300">
    <Window.ContextMenu>
        <ContextMenu>
            <MenuItem Header="Window menu" />
        </ContextMenu>
    </Window.ContextMenu>
    <GroupBox Header="GroupBox">
        <GroupBox.ContextMenu>
            <ContextMenu>
                <MenuItem Header="GroupBox menu" />
            </ContextMenu>
        </GroupBox.ContextMenu>
    </GroupBox>
</Window>

So when you click inside the GroupBox, you always get the "Window menu" coming up, but I want the "Group menu" instead.

Does anyone know why this is happening and potentially how I go about resolving it?

Many thanks.

OJ

Answer 1

The group box is essentially an empty border with a header label. In the case that there is no content in the group box, your clicks are actually landing on the owning Window, which explains why "Window menu" is coming up. If you put some content into the group box which fills it entirely, you will see the group box context menu come up at all times:

<GroupBox Header="GroupBox">
   <GroupBox.ContextMenu>
        <ContextMenu>
            <MenuItem Header="GroupBox menu"/>
        </ContextMenu>
    </GroupBox.ContextMenu>
    <Label HorizontalAlignment="Stretch" VerticalAlignment="Stretch"/> 
</GroupBox>

Answer 2

The actual problem is that many of the controls don't have a background. I think you will find that if you add a background to your control, your context menu will work. You can set the background to transparent if you don't want it to show