Swift version: 5.6
All views and subclasses are rendered using the
drawRect() method, but you should never call that method directly yourself. Instead, it gets called by the system whenever drawing is required, which allows it to to avoid multiple redraws if
drawRect() is called several times in a row.
Instead, if you want a view to redraw immediately, you should call its
setNeedsDisplay() method like this:
That will ask UIKit to redraw the button using
drawRect(), but only if a redraw is not already queued.
SAVE 50% To celebrate Black Friday, all our books and bundles are half price, so you can take your Swift knowledge further without spending big! Get the Swift Power Pack to build your iOS career faster, get the Swift Platform Pack to builds apps for macOS, watchOS, and beyond, or get the Swift Plus Pack to learn advanced design patterns, testing skills, and more.
Available from iOS 2.0
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.
Link copied to your pasteboard.