Ios 底部圆角的Customview在Swift中未获得阴影效果

我正在展示一些自定义视图。我试图只显示底部阴影的底角。它可以获得底部圆角，但阴影效果不会出现。如果我去掉角，阴影效果就会出现

func showCustomView() {
    self.customview.layer.shadowOffset = CGSize(width: 0, height: 5)
    self.customview.layer.shadowOpacity = 0.6
    self.customview.layer.shadowRadius = 3.0
    self.customview.layer.shadowColor = UIColor.gray.cgColor
    self.customview.roundCorners(corners: [.bottomLeft, .bottomRight], radius: 12)
}

    extension UIView {
        
        func roundCorners(corners: UIRectCorner, radius: CGFloat) {
            
            if #available(iOS 11, *) {
                self.clipsToBounds = true
                self.layer.cornerRadius = radius
                var masked = CACornerMask()
                if corners.contains(.topLeft) { masked.insert(.layerMinXMinYCorner) }
                if corners.contains(.topRight) { masked.insert(.layerMaxXMinYCorner) }
                if corners.contains(.bottomLeft) { masked.insert(.layerMinXMaxYCorner) }
                if corners.contains(.bottomRight) { masked.insert(.layerMaxXMaxYCorner) }
                self.layer.maskedCorners = masked
            }
            else {
                let path = UIBezierPath(roundedRect: bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
                let mask = CAShapeLayer()
                mask.path = path.cgPath
                layer.mask = mask
            }
        }
    }

---

有什么建议吗？

删除

self.clipstobunds=true

从

圆角（…）

示例

import UIKit

class MissingShadowViewController: UIViewController {

    @IBOutlet weak var customView: UIView!
    
    override func viewDidLoad() {
        super.viewDidLoad()

        showCustomView()
    }
    
    func showCustomView() {
        self.customView.layer.shadowOffset = CGSize(width: 0, height: 5)
        self.customView.layer.shadowOpacity = 0.6
        self.customView.layer.shadowRadius = 3.0
        self.customView.layer.shadowColor = UIColor.gray.cgColor
        self.customView.roundCorners(corners: [.bottomLeft, .bottomRight], radius: 12)
    }

}

extension UIView {
    
    func roundCorners(corners: UIRectCorner, radius: CGFloat) {
        
        if #available(iOS 11, *) {
            // clipping here will hide shadows
            // self.clipsToBounds = true
            self.layer.cornerRadius = radius
            var masked = CACornerMask()
            if corners.contains(.topLeft) { masked.insert(.layerMinXMinYCorner) }
            if corners.contains(.topRight) { masked.insert(.layerMaxXMinYCorner) }
            if corners.contains(.bottomLeft) { masked.insert(.layerMinXMaxYCorner) }
            if corners.contains(.bottomRight) { masked.insert(.layerMaxXMaxYCorner) }
            self.layer.maskedCorners = masked
        }
        else {
            let path = UIBezierPath(roundedRect: bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
            let mask = CAShapeLayer()
            mask.path = path.cgPath
            layer.mask = mask
        }
    }
}

---

self.clipsToBounds=false（默认为false，因此删除行也可以）尝试过，但没有效果，仍然阴影不显示@danielmarxwird，复制粘贴您的代码，对我来说效果很好。在哪里调用showCustomView（）override init（frame:CGRect）{super.init（frame:frame）self.showCustomView（）}必需的init？（coder:NSCoder）{super.init（coder:coder）self.showCustomView（）}这里我已经在这个函数的圆角处调用了{函数我只将其设置为真，但阴影仍然不会出现在底部