在swift中创建一个只有两个圆角的矩形？

Question

我需要在swift中创建一个只有两个圆角的矩形（Objective C代码也可以）。

目前我的代码正在创建两个矩形

CGPathCreateWithRoundedRect(CGRectMake(0, 0, 30, 60), 5, 5, nil);

和

CGPathCreateWithRoundedRect(CGRectMake(0, 0, 30, 60), 0, 0, nil);

合并它们（有两个直角和两个圆角）但我对代码不满意，我很确定应该有更好的方法来做到这一点。

我是iOS和图形开发的新手。

Answer 1

在Swift 2.3中你可以这样做

let maskPath = UIBezierPath(roundedRect: anyView.bounds,
            byRoundingCorners: [.BottomLeft, .BottomRight],
            cornerRadii: CGSize(width: 10.0, height: 10.0))

let shape = CAShapeLayer()
shape.path = maskPath.CGPath
view.layer.mask = shape

---

在Objective-C中，您可以使用UIBezierPath类方法

bezierPathWithRoundedRect:byRoundingCorners:cornerRadii:

示例实施 -

// set the corner radius to the specified corners of the passed container
- (void)setMaskTo:(UIView*)view byRoundingCorners:(UIRectCorner)corners
{
    UIBezierPath *rounded = [UIBezierPath bezierPathWithRoundedRect:view.bounds
                                                  byRoundingCorners:corners
                                                        cornerRadii:CGSizeMake(10.0, 10.0)];
    CAShapeLayer *shape = [[CAShapeLayer alloc] init];
    [shape setPath:rounded.CGPath];
    view.layer.mask = shape;
}

并将上述方法称为 -

[self setMaskTo:anyView byRoundingCorners:UIRectCornerBottomLeft | UIRectCornerBottomRight];

Answer 2

iOS 11+仅限|您可以查看iOS使用情况统计here

Explanation

由于CACornerMask rawValue是UInt，你知道CACornerMask rawValue是每个CACornerMask.Element rawValue的总和

进一步来说：

• TopLeft（layerMinXMinYCorner）= 1
• TopRight（layerMaxXMinYCorner）= 2
• BottomLeft（layerMinXMaxYCorner）= 4
• BottomRight（layerMaxXMaxYCorner）= 8

因此，例如，如果您想要左上角和右上角，您只需键入CACornerMask(rawValue: 3)即可。

---

 Example

下面是UIView的简单扩展

extension UIView {
    enum Corner:Int {
        case bottomRight = 0,
        topRight,
        bottomLeft,
        topLeft
    }

    private func parseCorner(corner: Corner) -> CACornerMask.Element {
        let corners: [CACornerMask.Element] = [.layerMaxXMaxYCorner, .layerMaxXMinYCorner, .layerMinXMaxYCorner, .layerMinXMinYCorner]
        return corners[corner.rawValue]
    }

    private func createMask(corners: [Corner]) -> UInt {
        return corners.reduce(0, { (a, b) -> UInt in
            return a + parseCorner(corner: b).rawValue
        })
    }

    func roundCorners(corners: [Corner], amount: CGFloat = 5) {
        layer.cornerRadius = amount
        let maskedCorners: CACornerMask = CACornerMask(rawValue: createMask(corners: corners))
        layer.maskedCorners = maskedCorners
    }
}

你可以这样使用：

let myRect = UIView(frame: CGRect(x: 0, y: 0, width: 200, height: 50))
myRect.roundCorners(corners: [.topRight, .topLeft])

Answer 3

Objective-C版iWasRobbed的回答：

UIView的+ RoundCorners.h

#import <UIKit/UIKit.h>

@interface UIView (RoundCorners)

/**
 Rounds the given set of corners to the specified radius

 - parameter corners: Corners to round
 - parameter radius:  Radius to round to
 */
- (void)roundCorners:(UIRectCorner)corners radius:(CGFloat)radius;

/**
 Rounds the given set of corners to the specified radius with a border

 - parameter corners:     Corners to round
 - parameter radius:      Radius to round to
 - parameter borderColor: The border color
 - parameter borderWidth: The border width
 */
- (void)roundCorners:(UIRectCorner)corners radius:(CGFloat)radius borderColor:(UIColor *)borderColor borderWidth:(CGFloat)borderWidth;

/**
 Fully rounds an autolayout view (e.g. one with no known frame) with the given diameter and border

 - parameter diameter:    The view's diameter
 - parameter borderColor: The border color
 - parameter borderWidth: The border width
 */
- (void)fullyRoundWithDiameter:(CGFloat)diameter borderColor:(UIColor *)borderColor borderWidth:(CGFloat)borderWidth;

@end

UIView的+ RoundCorners.m

#import "UIView+RoundCorners.h"

@implementation UIView (RoundCorners)

- (void)roundCorners:(UIRectCorner)corners radius:(CGFloat)radius {
    [self _roundCorners:corners radius:radius];
}

- (void)roundCorners:(UIRectCorner)corners radius:(CGFloat)radius borderColor:(UIColor *)borderColor borderWidth:(CGFloat)borderWidth {
    CAShapeLayer *mask = [self _roundCorners:corners radius:radius];
    [self addBorderWithMask:mask borderColor:borderColor borderWidth:borderWidth];
}

- (void)fullyRoundWithDiameter:(CGFloat)diameter borderColor:(UIColor *)borderColor borderWidth:(CGFloat)borderWidth {
    self.layer.masksToBounds = YES;
    self.layer.cornerRadius = diameter / 2;
    self.layer.borderWidth = borderWidth;
    self.layer.borderColor = borderColor.CGColor;
}

- (CAShapeLayer *)_roundCorners:(UIRectCorner)corners radius:(CGFloat)radius {
    UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:self.bounds byRoundingCorners:corners cornerRadii:CGSizeMake(radius, radius)];
    CAShapeLayer *mask = [CAShapeLayer layer];
    mask.path = path.CGPath;
    self.layer.mask = mask;
    return mask;
}

- (void)addBorderWithMask:(CAShapeLayer *)mask borderColor:(UIColor *)borderColor borderWidth:(CGFloat)borderWidth {
    CAShapeLayer *borderLayer = [CAShapeLayer layer];
    borderLayer.path = mask.path;
    borderLayer.fillColor = UIColor.clearColor.CGColor;
    borderLayer.strokeColor = borderColor.CGColor;
    borderLayer.lineWidth = borderWidth;
    borderLayer.frame = self.bounds;
    [self.layer addSublayer:borderLayer];
}

@end

Answer 4

一个简单的黑客可能如下。在图像中获取如下图所示的视图。红色视图将具有圆角，黄色视图（红色视图内）将防止角落圆角

现在写下Red View的代码。

        self.myView.layer.cornerRadius = 15

确保不要将任何代码写为clipsToBounds = true或masksToBounds = true。

下图是结果

黄色视图的放置将决定哪两个角不会被舍入。希望这很容易实现。

Answer 5

这是一个快速Swift 3扩展，您可以使用它来进行舍入和可选边框。

注意：如果您正在使用autolayout，则可能需要在视图受约束后在viewDidLayoutSubviews或layoutSubviews之类的视图生命周期回调中调用此方法。

import UIKit

extension UIView {

    /**
     Rounds the given set of corners to the specified radius

     - parameter corners: Corners to round
     - parameter radius:  Radius to round to
     */
    func round(corners: UIRectCorner, radius: CGFloat) {
        _ = _round(corners: corners, radius: radius)
    }

    /**
     Rounds the given set of corners to the specified radius with a border

     - parameter corners:     Corners to round
     - parameter radius:      Radius to round to
     - parameter borderColor: The border color
     - parameter borderWidth: The border width
     */
    func round(corners: UIRectCorner, radius: CGFloat, borderColor: UIColor, borderWidth: CGFloat) {
        let mask = _round(corners: corners, radius: radius)
        addBorder(mask: mask, borderColor: borderColor, borderWidth: borderWidth)
    }

    /**
     Fully rounds an autolayout view (e.g. one with no known frame) with the given diameter and border

     - parameter diameter:    The view's diameter
     - parameter borderColor: The border color
     - parameter borderWidth: The border width
     */
    func fullyRound(diameter: CGFloat, borderColor: UIColor, borderWidth: CGFloat) {
        layer.masksToBounds = true
        layer.cornerRadius = diameter / 2
        layer.borderWidth = borderWidth
        layer.borderColor = borderColor.cgColor;
    }

}

private extension UIView {

    @discardableResult func _round(corners: UIRectCorner, radius: CGFloat) -> CAShapeLayer {
        let path = UIBezierPath(roundedRect: bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
        let mask = CAShapeLayer()
        mask.path = path.cgPath
        self.layer.mask = mask
        return mask
    }

    func addBorder(mask: CAShapeLayer, borderColor: UIColor, borderWidth: CGFloat) {
        let borderLayer = CAShapeLayer()
        borderLayer.path = mask.path
        borderLayer.fillColor = UIColor.clear.cgColor
        borderLayer.strokeColor = borderColor.cgColor
        borderLayer.lineWidth = borderWidth
        borderLayer.frame = bounds
        layer.addSublayer(borderLayer)
    }

}

Answer 6

Swift 4 +，iOS 11+

如果你已经有一个名为UIView的myView被引用为IBOutlet，请尝试在ViewDidLoad()或者加载它的任何地方添加以下两行：

myView.layer.cornerRadius = 10
myView.layer.maskedCorners = [.layerMinXMaxYCorner, .layerMaxXMaxYCorner]

您可以将数组[]更改为MinX，MinY，MaxX和MaxY的任意组合，以选择所需的角。上面的例子围绕底部的两个角。

这只是另一种方法，根据您的设计可能会更简单一些。

Answer 7

Swift 3 - 当你需要围绕某些视图的特定角落时，有用的UIView扩展：

extension UIView {
  func round(corners: UIRectCorner, radius: CGFloat) {
    let path = UIBezierPath(roundedRect: bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
    let mask = CAShapeLayer()
    mask.path = path.cgPath
    self.layer.mask = mask
  }
}

然后就像这样使用它：

someView.round(corners: [.topLeft, .topRight], radius: 5)

Answer 8

在Sanjay的优秀答案的基础上，我为Swift 2.3编写了一个快速的CALayer扩展，以防你需要不止一次地做这种“只围绕某些角落”的事情。

extension CALayer {
  func roundCorners(corners: UIRectCorner, radius: CGFloat) {
    let maskPath = UIBezierPath(roundedRect: bounds,
                                byRoundingCorners: corners,
                                cornerRadii: CGSize(width: radius, height: radius))

    let shape = CAShapeLayer()
    shape.path = maskPath.CGPath
    mask = shape
  }
}

用法：

myView.layer.roundCorners([.TopLeft, .TopRight], radius: myCornerRadius)

Swift 3.0（在这个例子中，边界来自视图而不是来自图层。使用视图中的边界使得此代码可以在UITableViewCell中使用视图。）：

func roundCorners(corners: UIRectCorner, radius: CGFloat, viewBounds: CGRect) {

    let maskPath = UIBezierPath(roundedRect: viewBounds,
                                byRoundingCorners: corners,
                                cornerRadii: CGSize(width: radius, height: radius))

    let shape = CAShapeLayer()
    shape.path = maskPath.cgPath
    mask = shape
}

用法：

myView.layer.roundCorners(corners: [.topLeft, .topRight], radius: myCornerRadius, viewBounds: bounds)

Answer 9

这是你在Swift 2.0中所做的

var maskPath = UIBezierPath(roundedRect: anyView.bounds,
        byRoundingCorners: [.BottomLeft, .BottomRight],
        cornerRadii: CGSize(width: 10.0, height: 10.0))

Answer 10

2017...

@IBDesignable
class RoundedEnds: UIView {

    override func layoutSubviews() { setup() } // "layoutSubviews" is best

    func setup() {
        let r = self.bounds.size.height / 2
        let path = UIBezierPath(roundedRect: self.bounds, cornerRadius:r)
        let mask = CAShapeLayer()
        mask.path = path.cgPath
        self.layer.mask = mask
    }
}

仅限某些角落，只需更改为：

roundedRect: self.bounds,
  byRoundingCorners: [.topLeft, .topRight],
  cornerRadii: CGSize(width: r, height: r)

请注意，像往常一样，Swift中有许多小的变化，例如常量的大写等。

Answer 11

更新了iWasRobbed使用Swift 3.0 GM版本的答案：

import UIKit

extension UIView {

    /**
     Rounds the given set of corners to the specified radius

     - parameter corners: Corners to round
     - parameter radius:  Radius to round to
     */
    func round(corners: UIRectCorner, radius: CGFloat) {
        _round(corners: corners, radius: radius)
    }

    /**
     Rounds the given set of corners to the specified radius with a border

     - parameter corners:     Corners to round
     - parameter radius:      Radius to round to
     - parameter borderColor: The border color
     - parameter borderWidth: The border width
     */
    func round(corners: UIRectCorner, radius: CGFloat, borderColor: UIColor, borderWidth: CGFloat) {
        let mask = _round(corners: corners, radius: radius)
        addBorder(mask: mask, borderColor: borderColor, borderWidth: borderWidth)
    }

    /**
     Fully rounds an autolayout view (e.g. one with no known frame) with the given diameter and border

     - parameter diameter:    The view's diameter
     - parameter borderColor: The border color
     - parameter borderWidth: The border width
     */
    func fullyRound(diameter: CGFloat, borderColor: UIColor, borderWidth: CGFloat) {
        layer.masksToBounds = true
        layer.cornerRadius = diameter / 2
        layer.borderWidth = borderWidth
        layer.borderColor = borderColor.cgColor;
    }

}

private extension UIView {

    @discardableResult func _round(corners: UIRectCorner, radius: CGFloat) -> CAShapeLayer {
        let path = UIBezierPath(roundedRect: bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
        let mask = CAShapeLayer()
        mask.path = path.cgPath
        self.layer.mask = mask
        return mask
    }

    func addBorder(mask: CAShapeLayer, borderColor: UIColor, borderWidth: CGFloat) {
        let borderLayer = CAShapeLayer()
        borderLayer.path = mask.path
        borderLayer.fillColor = UIColor.clear.cgColor
        borderLayer.strokeColor = borderColor.cgColor
        borderLayer.lineWidth = borderWidth
        borderLayer.frame = bounds
        layer.addSublayer(borderLayer)
    }

}

Answer 12

斯威夫特4：

let maskPath = UIBezierPath(
            roundedRect: view.bounds,
            byRoundingCorners: [.allCorners],
            cornerRadii: CGSize(width: 10.0, height: 10.0)
        )

let shape = CAShapeLayer()
shape.path = maskPath.cgPath

view.layer.mask = shape