[1.12.2] Undefined amount of categories for config gui

I'm currently using the @Config annotation to create a config gui. And now i want to add an undefined amount of categories to the config gui.

Similiar to adding an array of integers i tried this:

public static Category[] test = new Category[] {new Category()};

The problem is that when i open the category test nothing is in there. I also created a single instance of the category to test if it is working.

So is there a way to add an undefined amount of categories? Or would i have to create my own gui screen? (I know of the IModGuiFactory but i don't know what to do with it.)