Swift - 同时设置cornerRadius和阴影

Posted 2023-02-23

【中文标题】Swift - 同时设置cornerRadius和阴影

【英文标题】：Swift - set cornerRadius and shadow at the same time

【发布时间】：2019-11-03 16:24:58

【问题描述】：

我正在尝试将 cornerRadius 和 shadow（底部 + 右侧）设置为我的 UICollectionViewCell，但我的代码不起作用。 cornerRadius 和阴影都没有出现..

这是我的代码：

class MainWishlistCell: UICollectionViewCell 

let wishlistImage: UIImageView = 
    let v = UIImageView()
    v.translatesAutoresizingMaskIntoConstraints = false
    v.image = UIImage(named: "logoGroß")
    return v
()

let wishlistLabel: UILabel = 
    let v = UILabel()
    v.translatesAutoresizingMaskIntoConstraints = false
    v.text = "Main Wishlist"
    v.font = UIFont(name: "AvenirNext-DemiBold", size: 18)
    v.textColor = .darkGray
    v.textAlignment = .center
    return v
()

func addShadow() 
    let cornerRadius: CGFloat = 5
    self.wishlistImage.layer.shadowPath = UIBezierPath(roundedRect: self.wishlistImage.bounds, cornerRadius: cornerRadius).cgPath
    self.wishlistImage.layer.shadowRadius = cornerRadius
    self.wishlistImage.layer.shadowOffset = .zero
    self.wishlistImage.layer.shadowOpacity = 0.3
    self.wishlistImage.layer.shadowRadius = 10
    self.wishlistImage.layer.cornerRadius = cornerRadius
    self.wishlistImage.layer.shadowColor = UIColor.black.cgColor


override init(frame: CGRect) 
    super.init(frame: frame)
    commonInit()


required init?(coder: NSCoder) 
    super.init(coder: coder)
    commonInit()




func commonInit() -> Void 
    addShadow()
    contentView.addSubview(wishlistImage)
    contentView.addSubview(wishlistLabel)
    // constrain view to all 4 sides
    NSLayoutConstraint.activate([
        wishlistImage.topAnchor.constraint(equalTo: contentView.topAnchor),
        wishlistImage.leadingAnchor.constraint(equalTo: contentView.leadingAnchor),
        wishlistImage.trailingAnchor.constraint(equalTo: contentView.trailingAnchor),
        wishlistImage.heightAnchor.constraint(equalToConstant:150),

        wishlistLabel.topAnchor.constraint(equalTo: wishlistImage.bottomAnchor,constant: 1),
        wishlistLabel.bottomAnchor.constraint(equalTo: contentView.bottomAnchor),
        wishlistLabel.leadingAnchor.constraint(equalTo: contentView.leadingAnchor),
        wishlistLabel.trailingAnchor.constraint(equalTo: contentView.trailingAnchor),
    ])

【参考方案1】：

只需在addShadow()函数中添加一行代码：

layer.masksToBounds = false ---> which set the shadow of the view's layer.

然后将圆角半径添加到您的单元格：

contentview.clipsToBounds = true

【参考方案2】：

问题就在那个时候

addShadow()
contentView.addSubview(wishlistImage)
contentView.addSubview(wishlistLabel)

图片bounds为零

self.wishlistImage.layer.shadowPath = UIBezierPath(roundedRect: 
             self.wishlistImage.bounds, 
             cornerRadius: cornerRadius).cgPath

所以你需要

var once = true 
override func layoutSubviews() 
   super.layoutSubviews()
   if once 
      addShadow()
      once = false
   

【讨论】：

我必须在哪里实现该 sn-p？对不起，不是很有经验:)

在MainWishlistCell类内

这对我没有任何作用