UIView shadow displaying incorrectly - swift

Question

I've run into this problem before, and usually been able to fix it by placing the code in viewWillLayoutSubviews(). This works in every other view controller I have and I just can't find a solution.
I have a UIView and I'm adding a shadow to it like this:
func setUpUI() {
for tile in roundedTiles {
tile.layer.cornerRadius = t.frame.height/2
tile.layer.shadowColor = UIColor.black.cgColor
tile.layer.shadowRadius = 10.0
tile.layer.shadowOpacity = 0.15
tile.layer.addSpread(spread: -10)
tile.layer.borderColor = GlobalConstants.Colors.lightGray.cgColor
tile.layer.borderWidth = 1
}
}
I then call it here:
override func viewWillLayoutSubviews() {
super.viewWillLayoutSubviews()
setUpUI()
}
However, this is what it looks like:
This is what it should look like, taken from another view controller where it's displaying correctly (and I have written the code there exactly the same):
After looking at other StackOverflow questions I've tried moving it to viewDidLayoutSubviews(), viewDidLoad(), and adding tile.layoutIfNeeded(). Nothing is working. Would really appreciate some help!

Answer 1

First, I would recommend subclassing UIView for your tiles and add the shadow and rounded corners in the init method, rather than adding it via the parent view controller.
The trick to getting rounded corners with a shadow is adding the shadow to the view itself, and then adding a subview for the rounded corners, which you can maskToBounds without affecting the parent.
So:
class roundedTile: UIView {
required init?(coder: NSCoder) {
super.init(coder: coder)
self.layer.cornerRadius = self.frame.height/2
// Add shadow to parent view
self.layer.shadowColor = UIColor.black.cgColor
self.layer.shadowOffset = CGSize(width: 5.0, height: 0.0)
self.layer.shadowOpacity = 0.15
self.layer.shadowRadius = 10.0
// Create subview for rounded corners
let subView = UIView()
subView.frame.size = self.frame.size
subView.layer.cornerRadius = frame.height/2
subView.layer.borderColor = UIColor.lightGray.cgColor
subView.layer.borderWidth = 1
subView.layer.masksToBounds = true
self.addSubview(subView)
}
}
Season to taste the shadow offset/radius/opacity.