How to tell the engine to use a subclass of a Source class instead of the parent?

Hi, I’ve created a class called MyGameViewport client, its parent is GameViewport (located in the source code). As the subclass has been created through “Add code to project” it’s been saved and built with the code of that project, but a printing debugging function shows it’s not being used by the engine.

How to tell the engine to substitute the parent class with the created subclass?

Any ideas?

Check project settings, there a lot of default class settings there, if not then some class might have default class varable

Yes, actually that’s it. GameViewportClient to use can be set there. Thanks!