Adding Interface to UserWidget via Editor does not work properly

Actually this thread is a result of a previous post : Adding Interface to UserWidget fails casting - UI - Unreal Engine Forums

How to reproduce:

  • Create an empty Interface class via c++;
  • Inside the editor, create a WidgetBlueprint, inside the Class Settings add the Interface previously created;
  • Via C++, create this widget and try to Cast<> to this new Interface. It returns null.
    • Also, call UKismetSystemLibrary::DoesImplementInterface and see it returns true;
  • Now, if you extend the UUserWidget via c++ and add this interface through code and try to cast it, it passes.

What is expected is that we could add interfaces via Blueprint and cast it properly, without the need to hardcode it via c++.


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Done, thanks!