How to add rounded corners to a UIView with gradient applied? - swift

Question

I've written custom subclass of UIView that draws a gradient inside of it:
import UIKit
#IBDesignable
class PlayerCellView: UIView {
var startColor: UIColor = UIColor(red:0.20, green:0.75, blue:1.00, alpha:1.00)
var endColor: UIColor = UIColor(red:0.07, green:0.42, blue:1.00, alpha:1.00)
override func draw(_ rect: CGRect) {
let context = UIGraphicsGetCurrentContext()
let colors = [startColor.cgColor, endColor.cgColor]
let locations : [CGFloat] = [0.0, 1.0]
let gradient = CGGradient(colorsSpace: CGColorSpaceCreateDeviceRGB(), colors: colors as CFArray, locations: locations)
context?.drawLinearGradient(gradient!, start: CGPoint.zero, end: CGPoint(x: 0, y: self.bounds.height), options: .drawsAfterEndLocation)
}
}
How would I now apply rounded edges to this view?

Answer 1

use this extension method:
extension UIView {
func addGradientLayer(with colors: [CGColor], startPoint: CGPoint, endPoint: CGPoint, locations: [NSNumber] = [0.0, 1.0], frame: CGRect = CGRect.zero) {
let gradientLayer = CAGradientLayer()
gradientLayer.colors = colors
gradientLayer.startPoint = startPoint
gradientLayer.endPoint = endPoint
gradientLayer.locations = locations
gradientLayer.frame = frame
gradientLayer.cornerRadius = self.layer.cornerRadius
self.layer.insertSublayer(gradientLayer, at: 0)
}
}

Answer 2

You can add a rounded corner UIView with gradient using the following method:
func makeCircularGradient(){
let circularView = UIView()
self.view.addSubview(circularView)
circularView.translatesAutoresizingMaskIntoConstraints = false
circularView.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
circularView.centerYAnchor.constraint(equalTo: self.view.centerYAnchor).isActive = true
circularView.widthAnchor.constraint(equalToConstant: 200).isActive = true
circularView.heightAnchor.constraint(equalToConstant: 200).isActive = true
self.view.layoutIfNeeded()
let gradient = CAGradientLayer()
gradient.frame = circularView.bounds
gradient.colors = [UIColor.blue.cgColor,
UIColor.red.cgColor]
gradient.startPoint = CGPoint(x: 0, y: 1)
gradient.endPoint = CGPoint(x: 1, y: 0)
circularView.layer.addSublayer(gradient)
let circularPath = CGMutablePath()
circularPath.addArc(center: CGPoint.init(x: circularView.bounds.width / 2, y: circularView.bounds.height / 2), radius: circularView.bounds.width / 2, startAngle: 0, endAngle: CGFloat.pi * 2, clockwise: true, transform: .identity)
let maskLayer = CAShapeLayer()
maskLayer.path = circularPath
maskLayer.fillRule = kCAFillRuleEvenOdd
maskLayer.fillColor = UIColor.red.cgColor
circularView.layer.mask = maskLayer
}
Make a UIView and set the constraints as you see fit
Make a CAGradientLayer with colours of your choice
Make a circular mask layer and apply to the UIView.
The result will be something like below:
Making a curved corner radius View with gradient is a little bit more difficult than the circular one. And can be done like :
func makeCurvedCornerGradient(){
let circularView = UIView()
self.view.addSubview(circularView)
circularView.translatesAutoresizingMaskIntoConstraints = false
circularView.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
circularView.centerYAnchor.constraint(equalTo: self.view.centerYAnchor).isActive = true
circularView.widthAnchor.constraint(equalToConstant: 200).isActive = true
circularView.heightAnchor.constraint(equalToConstant: 200).isActive = true
self.view.layoutIfNeeded()
let gradient = CAGradientLayer()
gradient.frame = circularView.bounds
gradient.colors = [UIColor.blue.cgColor,
UIColor.red.cgColor]
gradient.startPoint = CGPoint(x: 0, y: 1)
gradient.endPoint = CGPoint(x: 1, y: 0)
circularView.layer.addSublayer(gradient)
let circularPath = CGMutablePath()
circularPath.move(to: CGPoint.init(x: 20, y: 0))
circularPath.addLine(to: CGPoint.init(x: circularView.bounds.width - 20, y: 0))
circularPath.addQuadCurve(to: CGPoint.init(x: circularView.bounds.width, y: 20), control: CGPoint.init(x: circularView.bounds.width, y: 0))
circularPath.addLine(to: CGPoint.init(x: circularView.bounds.width, y: circularView.bounds.height - 20))
circularPath.addQuadCurve(to: CGPoint.init(x: circularView.bounds.width - 20, y: circularView.bounds.height), control: CGPoint.init(x: circularView.bounds.width, y: circularView.bounds.height))
circularPath.addLine(to: CGPoint.init(x: 20, y: circularView.bounds.height))
circularPath.addQuadCurve(to: CGPoint.init(x: 0, y: circularView.bounds.height - 20), control: CGPoint.init(x: 0, y: circularView.bounds.height))
circularPath.addLine(to: CGPoint.init(x: 0, y: 20))
circularPath.addQuadCurve(to: CGPoint.init(x: 20, y: 0), control: CGPoint.init(x: 0, y: 0))
let maskLayer = CAShapeLayer()
maskLayer.path = circularPath
maskLayer.fillRule = kCAFillRuleEvenOdd
maskLayer.fillColor = UIColor.red.cgColor
circularView.layer.mask = maskLayer
}
Change the values according to your need.
Output:

Answer 3

You can possibly use the Following Code:
func setGradientBorderWidthColor(view: UIView)
{
let gradientColor = CAGradientLayer()
gradientColor.frame = CGRect(origin: CGPoint.zero, size: view.frame.size)
gradientColor.colors = [UIColor.blue.cgColor, UIColor.green.cgColor]
let pathWithRadius = UIBezierPath(roundedRect:view.bounds, byRoundingCorners:[.topRight, .topLeft, .bottomLeft , .bottomRight], cornerRadii: CGSize(width: 20.0, height: 20.0))
let shape = CAShapeLayer()
shape.lineWidth = 3
shape.path = pathWithRadius.cgPath
shape.strokeColor = UIColor.black.cgColor
shape.fillColor = UIColor.clear.cgColor
gradientColor.mask = shape
view.layer.mask = shape
view.layer.addSublayer(gradientColor)
}
You can use this as:
let myView = UIView()
myView.backgroundColor = UIColor.gray
myView.frame = CGRect(x: 100, y: 100, width: 100, height: 100)
setGradientBorderWidthColor(view: myView)
self.view.addSubview(myView)
Output is like this:
Hope this Helps!