如何从顶部到视觉效果视图模糊添加淡入淡出-SWIFT

Question

如何从顶部向视觉效果视图模糊添加淡入淡出？ 我希望顶部边缘不可见。

示例：

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Answer 1

这对我有用

extension UIView{
    func createGradientBlur() {
        let gradientLayer = CAGradientLayer()
        gradientLayer.colors = [
        UIColor.white.withAlphaComponent(0).cgColor,
        UIColor.white.withAlphaComponent(1).cgColor]
        let viewEffect = UIBlurEffect(style: .light)
        let effectView = UIVisualEffectView(effect: viewEffect)
        effectView.frame = CGRect(x: self.bounds.origin.x, y: self.bounds.size.height, width: self.bounds.width, height: self.bounds.size.height)
        gradientLayer.frame = effectView.bounds
        gradientLayer.startPoint = CGPoint(x: 0.0, y: 0.0)
        gradientLayer.endPoint = CGPoint(x: 0.0 , y: 0.3)
        effectView.autoresizingMask = [.flexibleHeight]
        effectView.layer.mask = gradientLayer
        effectView.isUserInteractionEnabled = false //Use this to pass touches under this blur effect
        addSubview(effectView)

    }
}

使用方法：

var myView = UIView()
myView.createGradientBlur()