Delegate signature mismatch

[AlienRenders]

I’m trying to add a delegate in C++ for the OnClick event to my widget.

So I have the declaration:

DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FButtonClickedDelegate, UMenuButton*, Button);

UMenuButton is my custom widget.

Then I have the property;

  UPROPERTY(BlueprintAssignable, BlueprintCallable, Category = "UI")
  FButtonClickedDelegate OnButtonClicked;

The image above should be correct. But it’s giving me a signature mismatch error.

If I refresh the node, the error and the last pin goes away and it crashes during runtime.

I changed the signature of the delegate in C++. I think that may be the problem. Is there a way to fix this? I don’t want to use a different name for the delegate.

[Chatouille]

What does the tooltip say when you hover over the Button pin and the Self pin

[AlienRenders]

They both say Menu Button Object Reference. I think that’s correct. The Button one is correct for sure. And the delegate is on the base class, so Menu Button makes sense there too.

[AlienRenders]

If I duplicate the widget, the Button pin on my other delegates get changed to a reference to the Blueprint of the original, not the base class as defined by the delegate macro. And I never changed this delegate. I think my widget asset is completely corrupted.

[AlienRenders]

I tried recreating the widget blueprint from scratch and the delegate call is missing the Button input. So I don’t know what to do.

[AlienRenders]

Only thing that kind of works is renaming both the delegate type and property names. Even after that, I still get these warnings even though none of those names exist anymore.

I tried reparenting and reparenting back. There doesn’t seem to be a way to change delegate signatures after you use them the first time.

[AlienRenders]

Clear bug in Unreal Engine where it won’t update delegate signatures changed in C++. I worked around it by recreating the widget from scratch and renaming the properties and delegates.