At first, I thought creating a code module to the layout would be obvious by calling the code module the same name as the layout. It doesn't seem to work that way. Will you explain the steps to connecting a layout to a code module?
Well, I'm afraid that you are mixing up quite a few things.
Even for B4A !
You speak about a code module with an activity ?
If you have an Activity you have an Activit module ? Not a code module !!!
iOS is NOT Android !!!
You don't have ativities in iOS.
You have Pages, all in the same module.
If you have a concrete small project, showing the problem, we could look at, post it.