How to set corner radius of imageView?

Question

In Objective-C such line

self.mainImageView.layer.cornerRadius = CGRectGetWidth(self.mainImageView.frame)/4.0f;

does its job, I tried it in

Answer 1

You can define border radius of any view providing an "User defined Runtime Attributes", providing key path "layer.cornerRadius" of type string and then the value of radius you need ;) See attached images below:

Answer 2

I created an UIView extension which allows to round specific corners :

import UIKit

enum RoundType {
    case top
    case none
    case bottom
    case both
}

extension UIView {

    func round(with type: RoundType, radius: CGFloat = 3.0) {
        var corners: UIRectCorner

        switch type {
        case .top:
            corners = [.topLeft, .topRight]
        case .none:
            corners = []
        case .bottom:
            corners = [.bottomLeft, .bottomRight]
        case .both:
            corners = [.allCorners]
        }

        DispatchQueue.main.async {
            let path = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
            let mask = CAShapeLayer()
            mask.path = path.cgPath
            self.layer.mask = mask
        }
    }

}

Answer 3

Layer draws out of clip region, you need to set it to mask to bounds:

self.mainImageView.layer.masksToBounds = true

From the docs:

By default, the corner radius does not apply to the image in the layer’s contents property; it applies only to the background color and border of the layer. However, setting the masksToBounds property to true causes the content to be clipped to the rounded corners

Answer 4

Swift 3, Xcode 8, iOS 10

DispatchQueue.main.async {
  self.mainImageView.layer.cornerRadius = self.mainImageView.bounds.size.width / 2.0
  self.mainImageView.clipsToBounds = true
}

Answer 5

The easiest way is to create an UIImageView subclass (I have tried it and it's working perfectly on iPhone 7 and XCode 8):

class CIRoundedImageView: UIImageView {

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }

    override func awakeFromNib() {

        self.layoutIfNeeded()
        layer.cornerRadius = self.frame.height / 2.0
        layer.masksToBounds = true
    }
}

and then you can also set a border:

imageView.layer.borderWidth = 2.0

imageView.layer.borderColor = UIColor.blackColor().CGColor

Answer 6

in swift 3 'CGRectGetWidth' has been replaced by property 'CGRect.width'

    view.layer.cornerRadius = view.frame.width/4.0
    view.clipsToBounds = true