我正在研究时间线视图。我在图标的中心画了一条线，并用填充颜色画了一个圆圈。但问题是当我画圆圈时，它总是在图标的顶部。现在图标没有显示。我尝试了图层的 zposition 。这是我尝试过的
override func draw(_ rect: CGRect) {
if let anchor = anchorView(){
let centreRelativeToTableView = anchor.superview!.convert(anchor.center, to: self)
// print("Anchor x origin : \(anchor.frame.size.origin.x)")
timelinePoint.position = CGPoint(x: centreRelativeToTableView.x , y: centreRelativeToTableView.y/2)
timeline.start = CGPoint(x: centreRelativeToTableView.x , y: 0)
timeline.middle = CGPoint(x: timeline.start.x, y: anchor.frame.origin.y)
timeline.end = CGPoint(x: timeline.start.x, y: self.bounds.size.height)
timeline.draw(view: self.contentView)
let circlePath = UIBezierPath(arcCenter: CGPoint(x: anchor.center.x,y: anchor.center.y - 20), radius: CGFloat(20), startAngle: CGFloat(0), endAngle:CGFloat(M_PI * 2), clockwise: true)
let shapeLayer = CAShapeLayer()
shapeLayer.path = circlePath.cgPath
//change the fill color
shapeLayer.fillColor = UIColor.randomFlat.cgColor
// shapeLayer.fillColor = UIColor.clear.cgColor
//you can change the stroke color
shapeLayer.strokeColor = UIColor.white.cgColor
//you can change the line width
shapeLayer.lineWidth = 5
shapeLayer.zPosition = 0
anchor.alpha = 1
//Set Anchor Z position
anchor.layer.zPosition = 2
shapeLayer.zPosition = 1
anchor.layer.addSublayer(shapeLayer)
// Setting icon to layer
/*let imageLayer = CALayer()
imageLayer.contents = newImage
anchor.layer.addSublayer(imageLayer)*/
// timelinePoint.draw(view: self.contentView)
}else{
print("this should not happen")
}
}
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我想在圆圈顶部绘制带有白色色调的图标。请帮我