Implementing delegates in Swift, step by step.
James Rochabrun

This is a very clear tutorial, I had been wrapping my head over delegate pattern for a while and read many toturials. I was still a bit foggy in my head about delegate,. In the process of doing my coding exercise, I found this. Thank you.

I do have a question tho, in ClassAVC, how does the app know it is updating ClassBVC?