WPF Popup: How to put a border around the popup?

Question

I've got a Popup in my XAML to show some information. When the box pops up, it has no Border and appears to blend into the Background of the page. It just needs a Border, and ideally a drop-shadow behind it to show some sort of layering and focus.

Any ideas how to style a Popup to have a border and possibly the shadow-effect?

Answer 1

Thanks, I ended up giving it a 3D-like (hardly) appearance by setting the border like:

 <Border BorderBrush="White" BorderThickness="3,3,0,0">
            <Border BorderBrush="Black" BorderThickness="1,1,3,3">
</Border>
</Border>

Looks pretty decent!