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
简单的扩展
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
}
}
}
用法:
view.roundCorners(corners: [.bottomLeft, .bottomRight], radius: 12)
其他回答
简单的扩展
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
}
}
}
用法:
view.roundCorners(corners: [.bottomLeft, .bottomRight], radius: 12)
Swift代码示例:https://stackoverflow.com/a/35621736/308315
不直接。你必须:
创建一个CAShapeLayer 根据视图将其路径设置为CGPathRef。边界，但只有两个圆角(可能通过使用+[UIBezierPath bezierPathWithRoundedRect:byRoundingCorners:cornerRadii:]) 设置你的view.layer.mask为CAShapeLayer
试试这段代码，
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:view.bounds byRoundingCorners:( UIRectCornerTopLeft | UIRectCornerTopRight) cornerRadii:CGSizeMake(5.0, 5.0)];
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
maskLayer.frame = self.view.bounds;
maskLayer.path = maskPath.CGPath;
view.layer.mask = maskLayer;
注意，如果你有布局约束附加到它，你必须在你的UIView子类中按如下方式刷新它:
override func layoutSubviews() {
super.layoutSubviews()
roundCorners(corners: [.topLeft, .topRight], radius: 3.0)
}
如果你不这样做，它就不会出现。
和圆角，使用扩展:
extension UIView {
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
}
}
附加的视图控制器情况:无论你不能或不想子类化一个视图，你仍然可以舍入一个视图。通过覆盖viewWillLayoutSubviews()函数，从它的视图控制器中完成，如下所示:
class MyVC: UIViewController {
/// The view to round the top-left and top-right hand corners
let theView: UIView = {
let v = UIView(frame: CGRect(x: 10, y: 10, width: 200, height: 200))
v.backgroundColor = .red
return v
}()
override func loadView() {
super.loadView()
view.addSubview(theView)
}
override func viewWillLayoutSubviews() {
super.viewWillLayoutSubviews()
// Call the roundCorners() func right there.
theView.roundCorners(corners: [.topLeft, .topRight], radius: 30)
}
}
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
