Swift - Problems with corner radius and drop shadow
To expand on Imanou's post, it's possible to programmatically add the shadow layer in the custom button class
@IBDesignable class CustomButton: UIButton {
var shadowAdded: Bool = false
@IBInspectable var cornerRadius: CGFloat = 0 {
didSet {
layer.cornerRadius = cornerRadius
layer.masksToBounds = cornerRadius > 0
}
}
override func drawRect(rect: CGRect) {
super.drawRect(rect)
if shadowAdded { return }
shadowAdded = true
let shadowLayer = UIView(frame: self.frame)
shadowLayer.backgroundColor = UIColor.clearColor()
shadowLayer.layer.shadowColor = UIColor.darkGrayColor().CGColor
shadowLayer.layer.shadowPath = UIBezierPath(roundedRect: bounds, cornerRadius: self.cornerRadius).CGPath
shadowLayer.layer.shadowOffset = CGSize(width: 1.0, height: 1.0)
shadowLayer.layer.shadowOpacity = 0.5
shadowLayer.layer.shadowRadius = 1
shadowLayer.layer.masksToBounds = true
shadowLayer.clipsToBounds = false
self.superview?.addSubview(shadowLayer)
self.superview?.bringSubviewToFront(self)
}
}
My custom button with some shadow and rounded corners, I use it directly within the Storyboard
with no need to touch it programmatically.
Swift 4
class RoundedButtonWithShadow: UIButton {
override func awakeFromNib() {
super.awakeFromNib()
self.layer.masksToBounds = false
self.layer.cornerRadius = self.frame.height/2
self.layer.shadowColor = UIColor.black.cgColor
self.layer.shadowPath = UIBezierPath(roundedRect: self.bounds, cornerRadius: self.layer.cornerRadius).cgPath
self.layer.shadowOffset = CGSize(width: 0.0, height: 3.0)
self.layer.shadowOpacity = 0.5
self.layer.shadowRadius = 1.0
}
}
An alternative way to get more usable and consistent button.
Swift 2:
func getImageWithColor(color: UIColor, size: CGSize, cornerRadius:CGFloat) -> UIImage {
let rect = CGRectMake(0, 0, size.width, size.height)
UIGraphicsBeginImageContextWithOptions(size, false, 1)
UIBezierPath(
roundedRect: rect,
cornerRadius: cornerRadius
).addClip()
color.setFill()
UIRectFill(rect)
let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return image
}
let button = UIButton(type: .Custom)
button.frame = CGRectMake(20, 20, 200, 50)
button.setTitle("My Button", forState: UIControlState.Normal)
button.setTitleColor(UIColor.blackColor(), forState: UIControlState.Normal)
self.addSubview(button)
let image = getImageWithColor(UIColor.whiteColor(), size: button.frame.size, cornerRadius: 5)
button.setBackgroundImage(image, forState: UIControlState.Normal)
button.layer.shadowRadius = 5
button.layer.shadowColor = UIColor.blackColor().CGColor
button.layer.shadowOpacity = 0.5
button.layer.shadowOffset = CGSizeMake(0, 1)
button.layer.masksToBounds = false
Swift 3:
func getImageWithColor(_ color: UIColor, size: CGSize, cornerRadius:CGFloat) -> UIImage? {
let rect = CGRect(x: 0, y: 0, width: size.width, height: size.height)
UIGraphicsBeginImageContextWithOptions(size, false, 0)
color.setFill()
UIBezierPath(roundedRect: rect, cornerRadius: cornerRadius).addClip()
color.setFill()
UIRectFill(rect)
let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return image
}
let button = UIButton(type: .custom)
button.frame = CGRect(x:20, y:20, width:200, height:50)
button.setTitle("My Button", for: .normal)
button.setTitleColor(UIColor.black, for: .normal)
self.addSubview(button)
if let image = getImageWithColor(UIColor.white, size: button.frame.size, cornerRadius: 5) {
button.setBackgroundImage(image, for: .normal)
}
button.layer.shadowRadius = 5
button.layer.shadowColor = UIColor.black.cgColor
button.layer.shadowOpacity = 0.5
button.layer.shadowOffset = CGSize(width:0, height:1)
button.layer.masksToBounds = false
The following Swift 5 / iOS 12 code shows how to set a subclass of UIButton
that allows to create instances with rounded corners and shadow around it:
import UIKit
final class CustomButton: UIButton {
private var shadowLayer: CAShapeLayer!
override func layoutSubviews() {
super.layoutSubviews()
if shadowLayer == nil {
shadowLayer = CAShapeLayer()
shadowLayer.path = UIBezierPath(roundedRect: bounds, cornerRadius: 12).cgPath
shadowLayer.fillColor = UIColor.white.cgColor
shadowLayer.shadowColor = UIColor.darkGray.cgColor
shadowLayer.shadowPath = shadowLayer.path
shadowLayer.shadowOffset = CGSize(width: 2.0, height: 2.0)
shadowLayer.shadowOpacity = 0.8
shadowLayer.shadowRadius = 2
layer.insertSublayer(shadowLayer, at: 0)
//layer.insertSublayer(shadowLayer, below: nil) // also works
}
}
}
According to your needs, you may add a UIButton
in your Storyboard and set its class to CustomButton
or you may create an instance of CustomButton
programmatically. The following UIViewController
implementation shows how to create and use a CustomButton
instance programmatically:
import UIKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let button = CustomButton(type: .system)
button.setTitle("Button", for: .normal)
view.addSubview(button)
button.translatesAutoresizingMaskIntoConstraints = false
let horizontalConstraint = button.centerXAnchor.constraint(equalTo: view.centerXAnchor)
let verticalConstraint = button.centerYAnchor.constraint(equalTo: view.centerYAnchor)
let widthConstraint = button.widthAnchor.constraint(equalToConstant: 100)
let heightConstraint = button.heightAnchor.constraint(equalToConstant: 100)
NSLayoutConstraint.activate([horizontalConstraint, verticalConstraint, widthConstraint, heightConstraint])
}
}
The previous code produces the image below in the iPhone simulator: