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
Emma: . topright和。bottom right对你不起作用，可能是因为视图调用。roundCorners是在最终视图边界计算之前完成的。注意，贝塞尔路径在被调用时起源于视图边界。例如，如果自动布局将缩小视图，右侧的圆角可能在视图之外。 尝试在viewDidLayoutSubviews中调用它，其中视图的边界是final。
其他回答
这是最简单的答案:
yourView.layer.cornerRadius = 8
yourView.layer.masksToBounds = true
yourView.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner]
斯威夫特4
extension UIView {
func roundTop(radius:CGFloat = 5){
self.clipsToBounds = true
self.layer.cornerRadius = radius
if #available(iOS 11.0, *) {
self.layer.maskedCorners = [.layerMaxXMinYCorner, .layerMinXMinYCorner]
} else {
// Fallback on earlier versions
}
}
func roundBottom(radius:CGFloat = 5){
self.clipsToBounds = true
self.layer.cornerRadius = radius
if #available(iOS 11.0, *) {
self.layer.maskedCorners = [.layerMaxXMaxYCorner, .layerMinXMaxYCorner]
} else {
// Fallback on earlier versions
}
}
}
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
}
}
}
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。
// Create the path (with only the top-left corner rounded)
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:view.bounds
byRoundingCorners:(UIRectCornerBottomLeft | UIRectCornerBottomRight)
cornerRadii:CGSizeMake(7.0, 7.0)];
// Create the shape layer and set its path
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = cell.stripBlackImnageView.bounds;
maskLayer.path = maskPath.CGPath;
// Set the newly created shapelayer as the mask for the image view's layer
view.layer.mask = maskLayer;
