有没有办法为一个UIView的左上角和右上角设置角半径?
我尝试了下面的方法，但最终它再也看不到视图了。
UIView *view = [[UIView alloc] initWithFrame:frame];
CALayer *layer = [CALayer layer];
UIBezierPath *shadowPath = [UIBezierPath bezierPathWithRoundedRect:frame byRoundingCorners:(UIRectCornerTopLeft|UIRectCornerTopRight) cornerRadii:CGSizeMake(3.0, 3.0)];
layer.shadowPath = shadowPath.CGPath;
view.layer.mask = layer;
当前回答
使用这个扩展，它将涵盖一切。
extension UIView {
func roundTopCorners(radius: CGFloat = 10) {
self.clipsToBounds = true
self.layer.cornerRadius = radius
if #available(iOS 11.0, *) {
self.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner]
} else {
self.roundCorners(corners: [.topLeft, .topRight], radius: radius)
}
}
func roundBottomCorners(radius: CGFloat = 10) {
self.clipsToBounds = true
self.layer.cornerRadius = radius
if #available(iOS 11.0, *) {
self.layer.maskedCorners = [.layerMinXMaxYCorner, .layerMaxXMaxYCorner]
} else {
self.roundCorners(corners: [.bottomLeft, .bottomRight], radius: radius)
}
}
private func roundCorners(corners: UIRectCorner, radius: CGFloat) {
let path = UIBezierPath(roundedRect: bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
let mask = CAShapeLayer()
mask.path = path.cgPath
layer.mask = mask
}
}
然后像这样使用它:-
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
self.yourView.roundTopCorners()
}
注意:-我建议你不要把这段代码放在viewDidLayoutSubviews()中，因为每当视图更新时，你都会在里面得到调用。所以使用viewDidAppear()，它会像一个咒语一样工作。
其他回答
我不知道为什么你的解决方案没有工作，但下面的代码是为我工作。创建一个贝塞尔蒙版，并将其应用到您的视图。在下面的代码中，我将_backgroundView的底角圆角化为3个像素。self是一个自定义的UITableViewCell:
UIBezierPath *maskPath = [UIBezierPath
bezierPathWithRoundedRect:self.backgroundImageView.bounds
byRoundingCorners:(UIRectCornerBottomLeft | UIRectCornerBottomRight)
cornerRadii:CGSizeMake(20, 20)
];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = self.bounds;
maskLayer.path = maskPath.CGPath;
self.backgroundImageView.layer.mask = maskLayer;
Swift 2.0版本与一些改进:
let path = UIBezierPath(roundedRect:viewToRound.bounds, byRoundingCorners:[.TopRight, .BottomLeft], cornerRadii: CGSizeMake(20, 20))
let maskLayer = CAShapeLayer()
maskLayer.path = path.CGPath
viewToRound.layer.mask = maskLayer
Swift 3.0版本:
let path = UIBezierPath(roundedRect:viewToRound.bounds,
byRoundingCorners:[.topRight, .bottomLeft],
cornerRadii: CGSize(width: 20, height: 20))
let maskLayer = CAShapeLayer()
maskLayer.path = path.cgPath
viewToRound.layer.mask = maskLayer
这里的快速扩展
Stephane回答的另一个版本。
import UIKit
class RoundCornerView: UIView {
var corners : UIRectCorner = [.topLeft,.topRight,.bottomLeft,.bottomRight]
var roundCornerRadius : CGFloat = 0.0
override func layoutSubviews() {
super.layoutSubviews()
if corners.rawValue > 0 && roundCornerRadius > 0.0 {
self.roundCorners(corners: corners, radius: roundCornerRadius)
}
}
private func roundCorners(corners: UIRectCorner, radius: CGFloat) {
let path = UIBezierPath(roundedRect: bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
let mask = CAShapeLayer()
mask.path = path.cgPath
layer.mask = mask
}
}
如果你正在寻找一个界面构建器的唯一解决方案，有一个适用于iOS 11或更高版本。在这里可以看到我的答案:https://stackoverflow.com/a/58626264
下面是@JohnnyRockex的Swift版本的回答
extension UIView {
func roundCorners(_ corners: UIRectCorner, radius: CGFloat) {
let path = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
let mask = CAShapeLayer()
mask.path = path.cgPath
self.layer.mask = mask
}
}
view.roundCorners([.topLeft, .bottomRight], radius: 10)
Note
如果你正在使用自动布局，你需要子类化你的UIView，并在视图的layoutSubviews中调用roundCorners以获得最佳效果。
class View: UIView {
override func layoutSubviews() {
super.layoutSubviews()
self.roundCorners([.topLeft, .bottomLeft], radius: 10)
}
}
在swift 4.3中，修改代码后@apinho工作正常
extension UIView {
func roundCornersWithLayerMask(cornerRadii: CGFloat, corners: UIRectCorner) {
let path = UIBezierPath(roundedRect: bounds,
byRoundingCorners: corners,
cornerRadii: CGSize(width: cornerRadii, height: cornerRadii))
let maskLayer = CAShapeLayer()
maskLayer.path = path.cgPath
layer.mask = maskLayer
}
}
为您的视图使用此函数
YourViewName. roundCornersWithLayerMask(cornerRadii: 20,corners: [.topLeft,.topRight])
