ios - 虚线边框 UIImageView swift

Question

我正在尝试在 UIImageView 上使用 CALayer 添加虚线边框。我找到了一种方法，但它是否在 swift 中工作，我如何将它转换为 swift？ o 有另一个有边框的 imageView，所以使用 CALayer 是最好的解决方案，所以它们看起来很相似？我怎样才能得到这个

obj-c 代码到 swift？

- (CAShapeLayer *) addDashedBorderWithColor: (CGColorRef) color {
    CAShapeLayer *shapeLayer = [CAShapeLayer layer];

    CGSize frameSize = self.size;

    CGRect shapeRect = CGRectMake(0.0f, 0.0f, frameSize.width, frameSize.height);
    [shapeLayer setBounds:shapeRect];
    [shapeLayer setPosition:CGPointMake( frameSize.width/2,frameSize.height/2)];

    [shapeLayer setFillColor:[[UIColor clearColor] CGColor]];
    [shapeLayer setStrokeColor:color];
    [shapeLayer setLineWidth:5.0f];
    [shapeLayer setLineJoin:kCALineJoinRound];
    [shapeLayer setLineDashPattern:
    [NSArray arrayWithObjects:[NSNumber numberWithInt:10],
    [NSNumber numberWithInt:5],
  nil]];
    UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:shapeRect cornerRadius:15.0];
    [shapeLayer setPath:path.CGPath];

    return shapeLayer;
}

Answer 1

好的，我会在自定义 View 类中简单地这样做:

针对 Swift 4 进行了更新

class DashedBorderView: UIView {

    let _border = CAShapeLayer()

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        setup()
    }

    init() {
        super.init(frame: .zero)
        setup()
    }

    func setup() {
        _border.strokeColor = UIColor.black.cgColor
        _border.fillColor = nil
        _border.lineDashPattern = [4, 4]
        self.layer.addSublayer(_border)
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        _border.path = UIBezierPath(roundedRect: self.bounds, cornerRadius:10).cgPath
        _border.frame = self.bounds
    }
}