One of our xaml file would look like this:
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/
xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Presentation="clr-namespace:XXX.Modules.MyForm.Presentation"
xmlns:WinForms="clr-namespace:XXX.Modules.Common.WinForms"
xmlns:Converters="clr-namespace:XXX.Modules.Common.Converters"
<converters:booleanenumconverter key="YYYConverter">
[snipped other converters]
<DataTemplate DataType="{x:Type
Presentation:MyFormPresentationModel}">
[snipped template xaml]
</datatemplate>
</resourcedictionary>
Using the .Net reference source symbols (and/or deblector) I have been trying to step in on the exact bit of code which is setting that string instead of the correct proxied object or even the underlying instanced object, but with no luck so far.
I do think the issue may be with the xaml engine being unable to match the proxied type with the DataType of the DataTemplate, and I found out the .Net framework may perform that using the TypeExtension/MarkupExtension/DataTemplateSelector classes and possibly some implementation of the IXamlTypeResolver interface. From a quick search, I found out nowadays people is using those mostly to provide some support for generics in xaml (see i.e. "How To Get ParserContext" or "Limited generics support in Xaml").
From a purely theoretical point of view, I don't like much the idea to have to modify the xaml files to be able to intercept them, so I am not absolutely sure I have been missing something.
Before trying to spend some time on that (i.e. writing our own TypeExtension), I thought it could be better asking around if there is someone with previous experience or also some insight on this kind of scenario, so I have been posting a similar text to various newsgroups and mailing lists.
Last but not least, although I don't guess this is a Windsor bug (or at last I cannot yet see why it should be :)), we are using Castle project assemblies built from the revision 5380 of the 19th October 2008 in the trunk.
