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
最后，在iOS11中有CACornerMask ! 使用CACornerMask可以很容易地完成:
let view = UIView()
view.clipsToBounds = true
view.layer.cornerRadius = 10
view.layer.maskedCorners = [.layerMaxXMinYCorner, .layerMinXMinYCorner] // Top right corner, Top left corner respectively
其他回答
在Swift 4.2中，通过@IBDesignable创建它，如下所示:
@IBDesignable
class DesignableViewCustomCorner: UIView {
@IBInspectable var cornerRadious: CGFloat = 0 {
didSet {
let path = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: [.topLeft, .topRight], cornerRadii: CGSize(width: cornerRadious, height: cornerRadious))
let mask = CAShapeLayer()
mask.path = path.cgPath
self.layer.mask = mask
}
}
}
这是最简单的答案:
yourView.layer.cornerRadius = 8
yourView.layer.masksToBounds = true
yourView.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner]
一种编程的方法是创建一个UIView在UIView顶部有圆角的部分。或者你可以把顶部藏在什么东西下面。
一个可爱的扩展重用尤努斯Nedim Mehel解决方案
斯威夫特2.3
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
} }
使用
let view = UIView()
view.roundCornersWithLayerMask(10,[.TopLeft,.TopRight])
对于 SwiftUI
我找到了这些解决方案，你可以在这里查看https://stackoverflow.com/a/56763282/3716103
我强烈推荐第一个
选项1:使用Path + GeometryReader
(更多关于GeometryReader的信息:https://swiftui-lab.com/geometryreader-to-the-rescue/)
struct ContentView : View {
var body: some View {
Text("Hello World!")
.foregroundColor(.white)
.font(.largeTitle)
.padding(20)
.background(RoundedCorners(color: .blue, tl: 0, tr: 30, bl: 30, br: 0))
}
}
RoundedCorners
struct RoundedCorners: View {
var color: Color = .white
var tl: CGFloat = 0.0
var tr: CGFloat = 0.0
var bl: CGFloat = 0.0
var br: CGFloat = 0.0
var body: some View {
GeometryReader { geometry in
Path { path in
let w = geometry.size.width
let h = geometry.size.height
// Make sure we do not exceed the size of the rectangle
let tr = min(min(self.tr, h/2), w/2)
let tl = min(min(self.tl, h/2), w/2)
let bl = min(min(self.bl, h/2), w/2)
let br = min(min(self.br, h/2), w/2)
path.move(to: CGPoint(x: w / 2.0, y: 0))
path.addLine(to: CGPoint(x: w - tr, y: 0))
path.addArc(center: CGPoint(x: w - tr, y: tr), radius: tr, startAngle: Angle(degrees: -90), endAngle: Angle(degrees: 0), clockwise: false)
path.addLine(to: CGPoint(x: w, y: h - be))
path.addArc(center: CGPoint(x: w - br, y: h - br), radius: br, startAngle: Angle(degrees: 0), endAngle: Angle(degrees: 90), clockwise: false)
path.addLine(to: CGPoint(x: bl, y: h))
path.addArc(center: CGPoint(x: bl, y: h - bl), radius: bl, startAngle: Angle(degrees: 90), endAngle: Angle(degrees: 180), clockwise: false)
path.addLine(to: CGPoint(x: 0, y: tl))
path.addArc(center: CGPoint(x: tl, y: tl), radius: tl, startAngle: Angle(degrees: 180), endAngle: Angle(degrees: 270), clockwise: false)
}
.fill(self.color)
}
}
}
RoundedCorners_Previews
struct RoundedCorners_Previews: PreviewProvider {
static var previews: some View {
RoundedCorners(color: .pink, tl: 40, tr: 40, bl: 40, br: 40)
}
}
