Custom Class Not Drawing at Center - Swift - swift

Question

I have a UIView with a custom class of TimerView. I am trying to draw a dot in the exact center of the UIView but it is appearing at the bottom slightly off center:
Custom class is here:
import UIKit
class TimerView: UIView {
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
drawDot()
}
func drawDot() {
let midViewX = self.frame.midX
let midViewY = self.frame.midY
let dotPath = UIBezierPath(ovalIn: CGRect(x: midViewX, y: midViewY, width: 5, height: 5))
let dotLayer = CAShapeLayer()
dotLayer.path = dotPath.cgPath
dotLayer.strokeColor = UIColor.blue.cgColor
self.layer.addSublayer(dotLayer)
}
}

Answer 1

Here is the re-implementation of TimerView class. For UIView, init is not the best place to get the frame/bounds values because it might change once the autolayout applies the constraints in runtime. layoutSubviews is the best place to get the correct frame/bounds values for parent/child views and to setup the child space properties. Secondly you should be using parent view bounds to setup the child's frame.
class TimerView: UIView {
private var dotLayer: CAShapeLayer?
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
dotLayer = CAShapeLayer()
dotLayer?.strokeColor = UIColor.blue.cgColor
self.layer.addSublayer(dotLayer!)
}
override func layoutSubviews() {
super.layoutSubviews()
drawDot()
}
func drawDot() {
let midViewX = self.bounds.midX
let midViewY = self.bounds.midY
let dotPath = UIBezierPath(ovalIn: CGRect(x: midViewX, y: midViewY, width: 5, height: 5))
dotLayer?.path = dotPath.cgPath
}
}