我怎样才能用Swift编程渐变边界颜色UIButton

我如何devise编程UIButton像这样的渐变边框颜色？

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感谢帮助

Answer 1

let gradient = CAGradientLayer() gradient.frame = CGRect(origin: CGPointZero, size: self.myButton.frame.size) gradient.colors = [UIColor.blueColor().CGColor, UIColor.greenColor().CGColor] let shape = CAShapeLayer() shape.lineWidth = 2 shape.path = UIBezierPath(rect: self.myButton.bounds).CGPath shape.strokeColor = UIColor.blackColor().CGColor shape.fillColor = UIColor.clearColor().CGColor gradient.mask = shape self.myButton.layer.addSublayer(gradient) 

Swift 3版本：

  let gradient = CAGradientLayer() gradient.frame = CGRect(origin: CGPoint.zero, size: self.myButton.frame.size) gradient.colors = [UIColor.blue.cgColor, UIColor.green.cgColor] let shape = CAShapeLayer() shape.lineWidth = 2 shape.path = UIBezierPath(rect: self.myButton.bounds).cgPath shape.strokeColor = UIColor.black.cgColor shape.fillColor = UIColor.clear.cgColor gradient.mask = shape self.myButton.layer.addSublayer(gradient)