[iOS] The View Drawing Cycle

SwiftUI는 State, Binding, ObservableObject등의 값이 변경될때마다 뷰가 리프레시 되는데, UIKit이나 objc에선 어떻게 리프레시 되는지 몰라서 한번 찾아보았음.

iOS Drawing Concepts

• Moving or removing another view that was partially obscuring your view

• Making a previously hidden view visible again by setting its hidden property to NO

• Scrolling a view off of the screen and then back onto the screen

• Explicitly calling the setNeedsDisplay or setNeedsDisplayInRect: method of your view