iOS Swift Loading subview animation
import UIKit class CircleLoading : UIView { init () { super . init ( frame : . zero ) self . setupViews () } required init ?( coder : NSCoder ) { super . init ( coder : coder) self . setupViews () } private func setupViews () { self . backgroundColor = . clear var delay = 0.0 [- 50.0 , 0.0 , 50.0 ]. forEach { anchorX in let viewCircle = createCircle ( anchorX : anchorX) UIView . animate ( withDuration : 0.5 , delay : delay, ...