如何为 aspect fit 模式设置圆角的 UIImageView

Question

我一般用下面的代码来设置圆角

imageView.layer.cornerRadius = 10

当 imageView 设置为 Aspect Fill 时有效。

但是当imageView设置为Aspect Fit模式时，imageView和图片的比例不一样。圆角效果就看不出来了

背景颜色设置为绿色以显示圆角。

有什么方法可以设置'real image part'为圆角。

提前感谢您的回答。

Answer 1

试试这个可能对你有帮助：

import UIKit


class ViewController: UIViewController{

    @IBOutlet weak var myImageView: UIImageView!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

        myImageView.contentMode = UIViewContentMode.ScaleAspectFit
        myImageView.clipsToBounds = true
        //myImageView.layer.cornerRadius = 10.0
        myImageView.layer.masksToBounds = true

        let simpleImage = UIImage(named:"ipad5_einladung.jpg")
        let corneredImage = generateRoundCornerImage(simpleImage!, radius: 10)

        //Set cornered Image
        myImageView.image = corneredImage;

    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


    func generateRoundCornerImage(image : UIImage , radius : CGFloat) -> UIImage {

        let imageLayer = CALayer()
        imageLayer.frame = CGRectMake(0, 0, image.size.width, image.size.height)
        imageLayer.contents = image.CGImage
        imageLayer.masksToBounds = true
        imageLayer.cornerRadius = radius

        UIGraphicsBeginImageContext(image.size)
        imageLayer.renderInContext(UIGraphicsGetCurrentContext())
        let roundedImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return roundedImage
    }

}

Answer 2

您首先需要将宽度和高度设置为相同的值。然后像这样设置图像属性：

imgProfile_Pic.layer.cornerRadius = cell.imgProfile_Pic.frame.size.height / 2
imgProfile_Pic.layer.borderWidth = 3.0
imgProfile_Pic.layer.borderColor = UIColor.white.cgColor
imgProfile_Pic.clipsToBounds = true
imgProfile_Pic.layoutIfNeeded()

Answer 3

将此扩展用于 UIImageView：

extension UIImageView
{
    func roundCornersForAspectFit(radius: CGFloat)
    {
        if let image = self.image {

            //calculate drawingRect
            let boundsScale = self.bounds.size.width / self.bounds.size.height
            let imageScale = image.size.width / image.size.height

            var drawingRect: CGRect = self.bounds

            if boundsScale > imageScale {
                drawingRect.size.width =  drawingRect.size.height * imageScale
                drawingRect.origin.x = (self.bounds.size.width - drawingRect.size.width) / 2
            } else {
                drawingRect.size.height = drawingRect.size.width / imageScale
                drawingRect.origin.y = (self.bounds.size.height - drawingRect.size.height) / 2
            }
            let path = UIBezierPath(roundedRect: drawingRect, cornerRadius: radius)
            let mask = CAShapeLayer()
            mask.path = path.cgPath
            self.layer.mask = mask
        }
    }
}

Answer 4

像这样将图像视图四舍五入是非常简单的：

self.profileImageView?.clipsToBounds = true
self.profileImageView!.layer.cornerRadius = 10
self.profileImageView?.layer.borderWidth = 1.0
self.profileImageView?.contentMode = .ScaleAspectFit

但是为了使图像视图按图像比例四舍五入，我认为您必须将图像视图设置为 ScaleAspectFill 模式。

Answer 5

Swift 3 版本的有用的，被接受的答案在这里！

extension UIImageView {
func roundCornersForAspectFit(radius: CGFloat)
{
    if let image = self.image {

        //calculate drawingRect
        let boundsScale = self.bounds.size.width / self.bounds.size.height
        let imageScale = image.size.width / image.size.height

        var drawingRect : CGRect = self.bounds

        if boundsScale > imageScale {
            drawingRect.size.width =  drawingRect.size.height * imageScale
            drawingRect.origin.x = (self.bounds.size.width - drawingRect.size.width) / 2
        }else {
            drawingRect.size.height = drawingRect.size.width / imageScale
            drawingRect.origin.y = (self.bounds.size.height - drawingRect.size.height) / 2
        }
        let path = UIBezierPath(roundedRect: drawingRect, cornerRadius: radius)
        let mask = CAShapeLayer()
        mask.path = path.cgPath
        self.layer.mask = mask
        }
    }
}

Answer 6

这是已接受的答案，转换为 Objective-C：

@implementation UIImageView(Utils)

- (void)roundCornersForAspectFitWithRadius:(CGFloat)cornerRadius {
    if (self.image) {
        double boundsScale = self.bounds.size.width / self.bounds.size.height;
        double imageScale = self.image.size.width / self.image.size.height;

        CGRect drawingRect = self.bounds;

        if (boundsScale > imageScale) {
            drawingRect.size.width = drawingRect.size.height * imageScale;
            drawingRect.origin.x = (self.bounds.size.width - drawingRect.size.width) / 2;
        }
        else {
            drawingRect.size.height = drawingRect.size.width / imageScale;
            drawingRect.origin.y = (self.bounds.size.height - drawingRect.size.height) / 2;
        }
        UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:drawingRect cornerRadius:cornerRadius];
        CAShapeLayer *mask = [CAShapeLayer new];
        [mask setPath:path.CGPath];
        [self.layer setMask:mask];
    }
}

@end

Answer 7

我想对 Arun 的回答发表评论，以帮助那些在执行 Arun 的方法时遇到问题的人，但在 Collection View 中，您必须将 imageView 的框架启动为 Collection View 单元格的框架。

即

let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "identifier", for: indexPath) as UICollectionViewCell
let imageView = UIImageView(frame: cell.frame)

显然您想重构它和东西，但您明白了。

Answer 8

如果您在项目中使用SDWebImage，您可以执行以下操作：

myUIImageView.image = myUIImage.sd_roundedCornerImage(withRadius: 24, corners: .allCorners, borderWidth: 0, borderColor: nil)

如何为 aspect fit 模式设置圆角的 UIImageView

How to set UIImageView with rounded corners for aspect fit mode

ios

objective-c

swift

rounded-corners

cornerradius