What Needs To Be on Main Thread?

Question

I have written a little define called ensureInMainThread (and I use it quite a bit). However, I\'m not sure exactly which user interface methods require bei

Answer 1

With iOS 12, if you call setNeedsDisplay from a background thread, you get the following assert:

Main Thread Checker: UI API called on a background thread: -[UIView setNeedsDisplay]