Swift mask UIView constraints issues - ios

Question

I've created a mask view for my camera screen that blurs everything except for a small rectangle in the middle. I'm having issues when testing on different screen sizes. I'm testing on an 11 Pro and an 8. If my storyboard view has the proper device selected, the constraints look fine on the device. But if I switch phones without changing in the storyboard, it is incorrect. I'm programmatically creating the mask view. Any help would be much appreciated!
func setupBlur() {
if !UIAccessibility.isReduceTransparencyEnabled {
blurView.backgroundColor = .clear
let blurEffect = UIBlurEffect(style: .dark)
let blurEffectView = UIVisualEffectView(effect: blurEffect)
blurEffectView.frame = blurView.bounds
blurEffectView.translatesAutoresizingMaskIntoConstraints = false
blurEffectView.addConstraints(blurView.constraints)
blurView.addSubview(blurEffectView)
let maskView = UIView(frame: blurView.bounds)
maskView.translatesAutoresizingMaskIntoConstraints = false
maskView.addConstraints(blurView.constraints)
maskView.backgroundColor = .clear
let outerbezierPath = UIBezierPath.init(rect: blurView.bounds)
let croppedOriginX = (blurView.bounds.width / 2) - (captureView.bounds.width / 2)
let croppedOriginY = (blurView.bounds.height / 2) - (captureView.bounds.height / 2)
let frame = CGRect(x: croppedOriginX, y: croppedOriginY, width: captureView.bounds.width, height: captureView.bounds.height)
let innerRectPath = UIBezierPath.init(rect: frame)
outerbezierPath.append(innerRectPath)
outerbezierPath.usesEvenOddFillRule = true
let fillLayer = CAShapeLayer()
fillLayer.fillRule = kCAFillRuleEvenOdd
fillLayer.fillColor = UIColor.green.cgColor // any opaque color would work
fillLayer.path = outerbezierPath.cgPath
maskView.layer.addSublayer(fillLayer)
blurView.mask = maskView;
}
}

Answer 1

This happens because when you call setupBlur() from viewDidLoad, at the beginning blurView.bounds values are from stroyboard which you're working on it, and you are using these bounds to setup blurEffectView.frame before they are adjusted for your device's screen.
This is not the best solution, but I hope it will resolve your problem.
Try this:
override func viewDidLoad() {
super.viewDidLoad()
DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
self.setupBlur()
}
}

Answer 2

override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
self.setupBlur()
}

Answer 3

In my case, I've tried viewDidLayoutSubviews() instead of DispatchQue but it didn't work. However, viewDidLoad() worked for me.
override func viewDidAppear() {
self.setupBlur()
}