I found a solution with no code changes! I needed to add DataContext="{Binding}" to the ContentPresenter xaml, otherwise it was only being set from the Content property after failing to get the template. I still think there is a bug here as it works correctly without this in blend, but at ...

It is inside a ControlTemplate which is used to populate a ListBox, although I did try extracting ContentPresenter and having it independent of that, and I still got the same result so had assumed it wasn't related

Then I will continue to investigate. In its simplest form, the issue I am having is that the DataTemplate is not being set until after the ContentProvider tries to use it.
If you have any ideas as to why this is happening, I would be very appreciative. I will update if I am able to find any leads.

I have checked using the inspector, and I can see it is using the default template rather than the content template provided by the converter. From what I can see stepping through the code, the data context for the content presenter is not getting set until part way through OnPreApplyTemplate, after...

Yes the DataProperty is bound, and the converter's TryConvert is called, sets the result and returns true. I have stepped through the code at run time to confirm this is definitely the case. Below is my TryConvert function. m_Resources is an exposed property for the resource dictionary we wish to se...

I have a ContentPresenter and need to use a converter on the ContentTemplate binding. This converter returns a DataTemplate retrieved from a ResourceDictionary. It works fine in C#, but in C++ it is just displaying the viewmodel class name as text instead of the expected content. If I set the DataTe...

That is perfect, thank you! Of all the variations I tried I somehow missed that one

Hi, I am attempting to create an attached property class, with a registered property of type Noesis::Type, the idea being to be able to add the property to any node, and use the Type Extension to pass a type to my property. The property value would then be used to locate the instance of that type. I...

Just adding a note that the Path.TrimStart/End functionality used in the above example is not currently working in blend, although it is fine in C++.
I have raised a ticket for this. For reference #0001986

Thank you, I have submitted the following ticket #0001979