bringSubviewToFront problem?

Question

HI, I have Parentview-->Multiple childviews. when i use [self bringSubviewToFront:childview] in parentview, it works fine.but after adding grandchildview to childview,when

Answer 1

my contribution with the swift version from the checked solution

self.bringSubviewToFront(self.grandchildview.superview!)
self.grandchildview.superview!.bringSubviewToFront(self.grandchildview)