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
最简单的方法是用圆角层做一个蒙版。
CALayer *maskLayer = [CALayer layer];
maskLayer.frame = CGRectMake(0,0,maskWidth ,maskHeight);
maskLayer.contents = (__bridge id)[[UIImage imageNamed:@"maskImageWithRoundedCorners.png"] CGImage];
aUIView.layer.mask = maskLayer;
别忘了:
#import <QuartzCore/QuartzCore.h>
其他回答
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)
}
}
下面是一个实现的简短方法:
- (void)viewDidLoad {
[super viewDidLoad];
UIButton *openInMaps = [UIButton new];
[openInMaps setFrame:CGRectMake(15, 135, 114, 70)];
openInMaps = (UIButton *)[self roundCornersOnView:openInMaps onTopLeft:NO topRight:NO bottomLeft:YES bottomRight:NO radius:5.0];
}
- (UIView *)roundCornersOnView:(UIView *)view onTopLeft:(BOOL)tl topRight:(BOOL)tr bottomLeft:(BOOL)bl bottomRight:(BOOL)br radius:(float)radius {
if (tl || tr || bl || br) {
UIRectCorner corner = 0;
if (tl) {corner = corner | UIRectCornerTopLeft;}
if (tr) {corner = corner | UIRectCornerTopRight;}
if (bl) {corner = corner | UIRectCornerBottomLeft;}
if (br) {corner = corner | UIRectCornerBottomRight;}
UIView *roundedView = view;
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:roundedView.bounds byRoundingCorners:corner cornerRadii:CGSizeMake(radius, radius)];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = roundedView.bounds;
maskLayer.path = maskPath.CGPath;
roundedView.layer.mask = maskLayer;
return roundedView;
}
return view;
}
这是最简单的答案:
yourView.layer.cornerRadius = 8
yourView.layer.masksToBounds = true
yourView.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner]
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
只查看toppleft和TopRight角半径
lazy var footerBackgroundView: UIView = {
let view = UIView()
view.translatesAutoresizingMaskIntoConstraints = false
view.backgroundColor = .blue
//Make Corners Radius TopLeft & Top Right
view.clipsToBounds = true
view.layer.cornerRadius = 8
view.layer.maskedCorners = [.layerMaxXMinYCorner, .layerMinXMinYCorner]
return view
}()
