July 5, 2019
It usually doesn’t take beginning macOS/iOS developers long to discover NotificationCenter and see it as the solution to every single problem of passing data around to different controllers. And NotificationCenter is great, but it has some downsides. Notably, it is very easy to introduce retain cycles (and memory leaks) unless you are very careful to track and free the listener when the object is released. This has bitten me on several occasions. In general, excessive use of NotificationCenter ends up creating a difficult to maintain app where it is not entirely clear what is responding to what and where.