ios - CAGradientLayer 不改变背景颜色

Question

我想为我的 UIView 创建一个渐变作为背景色。我写了这段代码

gradient.colors = [UIColor.blue,UIColor.yellow]
        gradient.locations = [0.0 , 1.0]
        gradient.startPoint = CGPoint(x: 0.0, y: 1.0)
        gradient.endPoint = CGPoint(x: 1.0, y: 1.0)
        gradient.frame = CGRect(x: 0.0, y: 0.0, width: self.view.frame.size.width, height: self.view.frame.size.height)


self.view.layer.insertSublayer(gradient, at: 0)

但是在 Interface Builde 上的 View 仍然相同。如果我在代码之前添加这一行

self.view.backgroundColor = UIColor.clear

背景颜色变为白色

Answer 1

        let gradient: CAGradientLayer = CAGradientLayer()

        gradient.colors = [UIColor.blue.cgColor, UIColor.yellow.cgColor]
        gradient.locations = [0.0 , 1.0]
        gradient.startPoint = CGPoint(x: 0.0, y: 1.0)
        gradient.endPoint = CGPoint(x: 1.0, y: 1.0)
        gradient.frame = CGRect(x: 0.0, y: 0.0, width: self.view.frame.size.width, height: self.view.frame.size.height)

        self.view.layer.insertSublayer(gradient, at: 0)

试试这段代码。它适用于我 swift 3