title: XAML Design Time Preview for SwapChainPanel Element
body: <p>So if I'm using a <code>SwapChainPanel</code> element in the XAML designer, I get a design-time error saying the element can't be created. I see this out of the box with the <code>SwapChainPanel</code> <a href="http://code.msdn.microsoft.com/windowsapps/XAML-SwapChainPanel-00cb688b" rel="nofollow" title="sample app">sample app</a> from Microsoft. In Visual Studio 2013.3 I see an ugly "Cannot create an instance of "D3DPanel"." in the Design view for Scenario1.xaml.</p>
  
  <p>I was wondering if there were a way to provide fallback data for this element so I see something in the designer and in Blend. I've found some examples for designer data for data-bound controls, but so far nothing for DirectX.</p>
  
  <p>Edit: here's the stack trace from the designer in the Scenario1.xaml file from the SwapChainPanel demo. We seem to be able to create SwapChainPanels themselves, but when there's a custom C# class like D3DPanel, it chokes:</p>
  
  <p>at Microsoft.Expression.Platform.InstanceBuilders.InstanceBuilderOperations.InstantiateType(Type type, Boolean supportInternal)
     at Microsoft.Expression.Platform.InstanceBuilders.ClrObjectInstanceBuilder.InstantiateTargetType(IInstanceBuilderContext context, ViewNode viewNode)
     at Microsoft.Expression.WindowsXamlPlatform.InstanceBuilders.GridInstanceBuilder.InstantiateTargetType(IInstanceBuilderContext context, ViewNode viewNode)
     at Microsoft.Expression.Platform.InstanceBuilders.ClrObjectInstanceBuilder.Instantiate(IInstanceBuilderContext context, ViewNode viewNode)
     at Microsoft.Expression.WindowsXamlPlatform.InstanceBuilders.FrameworkElementInstanceBuilder.Instantiate(IInstanceBuilderContext context, ViewNode viewNode)
     at Microsoft.Expression.Platform.InstanceBuilders.ViewNodeManager.CreateInstance(IInstanceBuilder builder, ViewNode viewNode)</p>
  
  <p>The offending XAML element is something like <code>&lt;renderer:D3DPanel x:Name="DirectXPanel1" Height="300" Width="300" /&gt;</code>.</p>