The CGMutablePath
method addArc(tangent1End:tangent2End:radius:transform:)
旨在轻松制作圆角。
extension CGMutablePath {
static func bottomlessRoundedRect(in rect: CGRect, radius: CGFloat) -> CGMutablePath {
let path = CGMutablePath()
path.move(to: CGPoint(x: rect.minX, y: rect.maxY))
path.addArc(tangent1End: CGPoint(x: rect.minX, y: rect.minY), tangent2End: CGPoint(x: rect.maxX, y: rect.minY), radius: radius)
path.addArc(tangent1End: CGPoint(x: rect.maxX, y: rect.minY), tangent2End: CGPoint(x: rect.maxX, y: rect.maxY), radius: radius)
path.addLine(to: CGPoint(x: rect.maxX, y: rect.maxY))
return path
}
}
一旦有了该方法,最好使用自定义视图来管理CAShapeLayer
因此它可以自动适应尺寸变化。演示:
class MyFrameView: UIView {
override class var layerClass: AnyClass { return CAShapeLayer.self }
override func layoutSubviews() {
super.layoutSubviews()
let layer = self.layer as! CAShapeLayer
layer.lineWidth = 2
layer.strokeColor = UIColor.white.cgColor
layer.fillColor = nil
layer.path = CGMutablePath.bottomlessRoundedRect(in: bounds.insetBy(dx: 10, dy: 10), radius: 8)
}
}
import PlaygroundSupport
let view = UIView(frame: CGRect(x: 0, y: 0, width: 120, height: 60))
view.backgroundColor = #colorLiteral(red: 0.7034167647, green: 0.4845994711, blue: 0.6114708185, alpha: 1)
let frameView = MyFrameView(frame: view.bounds)
frameView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
view.addSubview(frameView)
let label = UILabel(frame: view.bounds)
label.text = "Hello"
label.textColor = .white
label.textAlignment = .center
view.addSubview(label)
PlaygroundPage.current.liveView = view
Result: