Ios 设置CALayer阴影如何打破自动布局约束？

我有cell的imageView阴影自定义：

override func layoutSubviews() {
    moviePosterImageView.layer.shadowOffset = .zero
    moviePosterImageView.layer.shadowColor = UIColor.black.cgColor
    moviePosterImageView.layer.shadowRadius = 5
    moviePosterImageView.layer.shadowOpacity = 1
    moviePosterImageView.layer.masksToBounds = false
    moviePosterImageView.layer.shadowPath = UIBezierPath(rect: moviePosterImageView.bounds).cgPath
}

但它打破了imageView的大小和限制。没有阴影，效果很好

---

在另一个swift文件中使用此代码，并在故事板或xib中轻松设置阴影

extension UIView {

@IBInspectable
var cornerRadius: CGFloat {
    get {
        return layer.cornerRadius
    }
    set {
        layer.cornerRadius = newValue
    }
}

@IBInspectable
var borderWidth: CGFloat {
    get {
        return layer.borderWidth
    }
    set {
        layer.borderWidth = newValue
    }
}

@IBInspectable
var borderColor: UIColor? {
    get {
        if let color = layer.borderColor {
            return UIColor(cgColor: color)
        }
        return nil
    }
    set {
        if let color = newValue {
            layer.borderColor = color.cgColor
        } else {
            layer.borderColor = nil
        }
    }
}

@IBInspectable
var shadowRadius: CGFloat {
    get {
        return layer.shadowRadius
    }
    set {
        layer.shadowRadius = newValue
    }
}

@IBInspectable
var shadowOpacity: Float {
    get {
        return layer.shadowOpacity
    }
    set {
        layer.shadowOpacity = newValue
    }
}

@IBInspectable
var shadowOffset: CGSize {
    get {
        return layer.shadowOffset
    }
    set {
        layer.shadowOffset = newValue
    }
}

@IBInspectable
var shadowColor: UIColor? {
    get {
        if let color = layer.shadowColor {
            return UIColor(cgColor: color)
        }
        return nil
    }
    set {
        if let color = newValue {
            layer.shadowColor = color.cgColor
        } else {
            layer.shadowColor = nil
        }
    }
  }
}

但它打破了imageView的大小和限制

是的，因为你忘了一开始就说

override func layoutSubviews() {
    super.layoutSubviews() // important

---

由于自动布局发生在

layoutSubviews

中，如果不调用

super

，则会阻止其运行

我打电话给super，但还是samei解决了我的问题，将imageView包装到一个容器中（仅视图）