WPF exception WindowStyle.None

Question

I have the MainAppWindow XAML like this:

<local:MyWindow
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
... 
xmlns:local="clr-namespace:MyNamespace" 
xmlns:System="clr-namespace:System;assembly=mscorlib"
x:Class="MyNamespace.MainAppWindow"
x:Name="MyWindow"
....
AllowsTransparency="True">

end I get this weird exception:

Notice some important things:

• In the Watch window the WindowStyle is ThreedBorderWindow
• MainAppWindow.AllowTransparency has been XAML-defined as True.

Is this a WPF bug? What is the cause? Is there a solution? Does somebody know a workaround?

Answer 1

Doesn't it exactly tell you the requirements? Change the WindowStyle to None, that is just the way it is.