Round Top Corners of a UIButton in Swift

Adding Extension of UIButton:

extension UIButton{    func roundedButton(){        let maskPath1 = UIBezierPath(roundedRect: bounds,            byRoundingCorners: [.topLeft , .topRight],            cornerRadii: CGSize(width: 8, height: 8))        let maskLayer1 = CAShapeLayer()        maskLayer1.frame = bounds        maskLayer1.path = maskPath1.cgPath        layer.mask = maskLayer1    }}

Calling in viewDidAppear/viewDidLayoutSubviews:

btnCorner.roundedButton()

Button Corner OutPut:

Swift 4: For latest iOS 11 onwards

override func viewDidLoad() {    super.viewDidLoad()    if #available(iOS 11.0, *) {        self.viewToRound.clipsToBounds = true        viewToRound.layer.cornerRadius = 20        viewToRound.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner]    } else {        // Fallback on earlier versions    }}

Earlier iOS (10,9 etc) Versions (works for iOS 11 too)

override func viewDidLayoutSubviews() {    self.viewToRound.clipsToBounds = true    let path = UIBezierPath(roundedRect: viewToRound.bounds,                            byRoundingCorners: [.topRight, .topLeft],                            cornerRadii: CGSize(width: 20, height: 20))    let maskLayer = CAShapeLayer()    maskLayer.path = path.cgPath    viewToRound.layer.mask = maskLayer}

For swift 3 Kirit Modi's answer is changed to:

extension UIButton {   func roundedButton(){       let maskPAth1 = UIBezierPath(roundedRect: self.bounds,                                    byRoundingCorners: [.topLeft , .topRight],                                    cornerRadii:CGSize(width:8.0, height:8.0))       let maskLayer1 = CAShapeLayer()       maskLayer1.frame = self.bounds       maskLayer1.path = maskPAth1.cgPath       self.layer.mask = maskLayer1   }}

At the start of the extension's file don't forget to add:

import UIKit

If you want an extension for a UIView with the option of rounding top or bottom corners you can use:

extension UIView {   func roundedCorners(top: Bool){       let corners:UIRectCorner = (top ? [.topLeft , .topRight] : [.bottomRight , .bottomLeft])               let maskPAth1 = UIBezierPath(roundedRect: self.bounds,                                    byRoundingCorners: corners,                                    cornerRadii:CGSize(width:8.0, height:8.0))       let maskLayer1 = CAShapeLayer()       maskLayer1.frame = self.bounds       maskLayer1.path = maskPAth1.cgPath       self.layer.mask = maskLayer1   }}

Which is called for a button as:

myButton.roundedCorners(top: true)