我正在尝试在弧内绘制一系列垂直线,但我无法做到这一点。我正在尝试使用CAShapeLayers
执行此操作。最终结果看起来像这样。
我知道如何使用CAShapeLayers绘制弧形弧和线段,但我似乎无法弄清楚如何在CAShapeLayer
我最初的方法是继承CAShapeLayer并在子类中尝试绘制垂直线。但是,我没有得到预期的结果。这是我的代码,用于向bezier点添加一行并尝试添加子图层。
class CustomLayer : CAShapeLayer {
override init() {
super.init()
}
func drawDividerLayer(){
print("Init has been called in custom layer")
print("The bounds of the custom layer is: \(bounds)")
print("The frame of the custom layer is: \(frame)")
let bezierPath = UIBezierPath()
let dividerShapeLayer = CAShapeLayer()
dividerShapeLayer.strokeColor = UIColor.redColor().CGColor
dividerShapeLayer.lineWidth = 1
let startPoint = CGPointMake(5, 0)
let endPoint = CGPointMake(5, 8)
let convertedStart = convertPoint(startPoint, toLayer: dividerShapeLayer)
let convertedEndPoint = convertPoint(endPoint, toLayer: dividerShapeLayer)
bezierPath.moveToPoint(convertedStart)
bezierPath.addLineToPoint(convertedEndPoint)
dividerShapeLayer.path = bezierPath.CGPath
addSublayer(dividerShapeLayer)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
class DrawView : UIView {
var customDrawLayer : CAShapeLayer!
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
//drawLayers()
}
override func drawRect(rect: CGRect) {
super.drawRect(rect)
}
func drawLayers() {
let bezierPath = UIBezierPath()
let startPoint = CGPointMake(5, 35)
let endPoint = CGPointMake(100, 35)
bezierPath.moveToPoint(startPoint)
bezierPath.addLineToPoint(endPoint)
let customLayer = CustomLayer()
customLayer.frame = CGPathGetBoundingBox(bezierPath.CGPath)
customLayer.drawDividerLayer()
customLayer.strokeColor = UIColor.blackColor().CGColor
customLayer.opacity = 0.5
customLayer.lineWidth = 8
customLayer.fillColor = UIColor.clearColor().CGColor
layer.addSublayer(customLayer)
customLayer.path = bezierPath.CGPath
}
但是,此代码会生成此图像:
我肯定有一个坐标空间问题/边界/框架问题,但我不太确定。我希望它的工作方式是从superLayer的顶部绘制到CustomLayer类内部的superLayer底部。但不仅如此,这必须使用贝塞尔路径addArcWithCenter:
方法,我还没有达到这个方法,因为我试图首先解决这个问题。任何帮助,将不胜感激。
答案 0 :(得分:3)
绘制由线条组成的弧线的最简单方法是使用lineDashPattern
:
let path = UIBezierPath(arcCenter: center, radius: radius, startAngle: 0, endAngle: CGFloat(M_PI), clockwise: false)
let arc = CAShapeLayer()
arc.path = path.CGPath
arc.lineWidth = 50
arc.lineDashPattern = [4,15]
arc.strokeColor = UIColor.lightGrayColor().CGColor
arc.fillColor = UIColor.clearColor().CGColor
view.layer.addSublayer(arc)
所以这是上面虚线弧下方的蓝色弧线。显然,我为了可见性而放大了它,但它说明了这个想法。