Swift Cannot Round the Corners of my UIButton

问题

I've looked at almost every stackoverflow solution and for some odd reason my button will not round the corners. Can someone check and see what im doing wrong?

let goToMapsButton = UIButton(type: .custom)
    scrollView.addSubview(goToMapsButton)
       _ = goToMapsButton.anchor(map.bottomAnchor, left: nil, bottom: seperator.topAnchor, right: self.view.rightAnchor, topConstant: 16, leftConstant: 0, bottomConstant: 16, rightConstant: 16, widthConstant: 50, heightConstant: 50)


    goToMapsButton.backgroundColor = .green
    goToMapsButton.layer.cornerRadius = 0.5 * goToMapsButton.bounds.size.width
    goToMapsButton.clipsToBounds = true
    goToMapsButton.layer.masksToBounds = true

Btw, Im doing this all in the viewDidLoad section of the view controller, if that info makes a difference.

Here is the full viewDidLoadClass for reference:` override func viewDidLoad() { super.viewDidLoad()

    let map = MKMapView()
    let view1 = UIView()
    view1.backgroundColor = .red

    let storeAddress = UILabel()
    storeAddress.text = "318 Atwood Avenue"
    storeAddress.font = UIFont.systemFont(ofSize: 20, weight: UIFont.Weight.medium)

    let storeCity = UILabel()
    storeCity.text = "Rainy River"
    storeCity.font = UIFont.systemFont(ofSize: 20, weight: UIFont.Weight.medium)

    let seperator = UIView()
    seperator.backgroundColor = .lightGray

    let goToMapsButton = UIButton(type: .custom)


    scrollView.addSubview(map)
    scrollView.addSubview(view1)
    scrollView.addSubview(storeAddress)
    scrollView.addSubview(storeCity)
    scrollView.addSubview(goToMapsButton)
    scrollView.addSubview(seperator)

    map.anchorToTop(scrollView.topAnchor, left: self.view.leftAnchor, bottom: nil, right: self.view.rightAnchor)
    map.heightAnchor.constraint(equalTo: self.view.heightAnchor, multiplier: 0.6).isActive = true

    _ = storeAddress.anchor(map.bottomAnchor, left: self.view.leftAnchor, bottom: nil, right: nil, topConstant: 16, leftConstant: 16, bottomConstant: 0, rightConstant: 0, widthConstant: 0, heightConstant: 0)
    _ = storeCity.anchor(storeAddress.bottomAnchor, left: self.view.leftAnchor, bottom: nil, right: nil, topConstant: 8, leftConstant: 16, bottomConstant: 0, rightConstant: 0, widthConstant: 0, heightConstant: 0)

    _ = goToMapsButton.anchor(map.bottomAnchor, left: nil, bottom: nil, right: self.view.rightAnchor, topConstant: 16, leftConstant: 0, bottomConstant: 16, rightConstant: 16, widthConstant: 50, heightConstant: 50)
    goToMapsButton.backgroundColor = .green
    print(goToMapsButton.frame.width)
    goToMapsButton.layer.cornerRadius = 0.25 * goToMapsButton.frame.width
    goToMapsButton.clipsToBounds = true
    goToMapsButton.layer.masksToBounds = true


    _ = seperator.anchor(storeCity.bottomAnchor, left: self.view.leftAnchor, bottom: nil, right: self.view.rightAnchor, topConstant: 8, leftConstant: 0, bottomConstant: 0, rightConstant: 0, widthConstant: 0, heightConstant: 1)

    view1.anchorToTop(map.bottomAnchor, left: self.view.leftAnchor, bottom: scrollView.bottomAnchor, right: self.view.rightAnchor)
    view1.heightAnchor.constraint(equalTo: self.view.heightAnchor, multiplier: 0.8).isActive = true

}`

回答1:

Move this code in viewWillLayoutSubviews:

override func viewWillLayoutSubviews() {
    super.viewWillLayoutSubviews()
    goToMapsButton.layer.cornerRadius = 0.25 * goToMapsButton.frame.width
}

Or create your custom class for button with rounded corners:

class RoundedButton: UIButton {
    @IBInspectable var cornerRadius: CGFloat = 0

    override func layoutSubviews() {
        super.layoutSubviews()
        clipsToBounds = true
        layer.cornerRadius = cornerRadius
    }
}

回答2:

Give your button a frame. like that

goToMapsButton.frame = CGRect(x: xposition, y:yposition, width: widthyouwant, height: heightyouwant)

as currently your size of button is zero 0*0.5 = zero thats why its not applying any radius. give it frame and it will work...

回答3:

UIButton might have a background UIImage with rounded corners. It allowes you to set a background UIImage for each UIControlState of your UIButton.

open class UIButton : UIControl, NSCoding {

    open func setBackgroundImage(_ image: UIImage?, for state: UIControlState)
}

If your UIButton's size is determined at runtime and the radius is fixed - you can use a resizable image:

open class UIImage : NSObject, NSSecureCoding {

    open func resizableImage(withCapInsets capInsets: UIEdgeInsets) -> UIImage
}

On the gif below I use UIImage with size = CGSize(width: 7, height: 7), corner radius = 3 and cap insets = UIEdgeInsets(top: 3, left: 3, bottom: 3, right: 3)

来源：https://stackoverflow.com/questions/48716990/swift-cannot-round-the-corners-of-my-uibutton

标签

ios

swift

uibutton

cornerradius