Ios 如何根据swift中圆圈的百分比填充笔画颜色

我正在创建一个圆，分为四个部分。笔画颜色应根据给定的百分比填写

    func showCircle() {
    DispatchQueue.main.asyncAfter(deadline: DispatchTime.now()+0.2) { [weak self] in
        guard let `self` = self else { return }
         
        self.layer.cornerRadius = self.frame.size.width / 2
        self.backgroundColor = .clear
           let total: Int = 4
           let width: CGFloat = 10.0
           let reducer: CGFloat = 0.0 // add gape b/w segments if reducer > 0
           let circlePath = UIBezierPath(arcCenter: CGPoint(x: self.frame.size.width / 2, y: self.frame.size.height / 2),
                                         radius: self.frame.size.width / 2,
                                         startAngle: CGFloat(-0.5 * Double.pi),
                                         endAngle: CGFloat(1.5 * Double.pi),
                                         clockwise: true)
      
        // these are the percentages 
        let percentages = [0.20, 0.15, 0.35, 0.30]
           
           for i in 1...total {
            
            let percentage = CGFloat(percentages[i - 1] )

            let circleShape = CAShapeLayer()
               circleShape.path = circlePath.cgPath
            
            switch i-1 {
            case 0:
                circleShape.strokeColor = #colorLiteral(red: 0.431372549, green: 0.231372549, blue: 0.631372549, alpha: 1)
                
            case 1:
                circleShape.strokeColor = #colorLiteral(red: 0.6784313725, green: 0.568627451, blue: 0.7882352941, alpha: 1)
                
            case 2:
                circleShape.strokeColor = #colorLiteral(red: 0.8470588235, green: 0.7960784314, blue: 0.8980392157, alpha: 1)
                
            case 3:
                circleShape.strokeColor = #colorLiteral(red: 0.9490196078, green: 0.937254902, blue: 0.9568627451, alpha: 1)
            default:
                circleShape.strokeColor = #colorLiteral(red: 0, green: 0, blue: 0, alpha: 1)
            }
               circleShape.fillColor = UIColor.clear.cgColor
               circleShape.lineWidth = width
               circleShape.strokeStart = CGFloat(CGFloat(i - 1) * percentage) + reducer
               circleShape.strokeEnd = CGFloat(CGFloat(i) * percentage) - reducer
            self.layer.addSublayer(circleShape)
           }
        }
}

错误结果：-这些颜色应根据百分比填充。

预期结果：-我们可以在这张图片中看到颜色是根据百分比正确填充的。

---

您的错误是strokeStart和strokeEnd应该在0到1之间，并且随着索引的增加而增加

这会有用的：

    // these are the percentages
    let percentages = [0.20, 0.15, 0.35, 0.30]
    
    for i in 1...total {
        let prevPercentage: Double = percentages.prefix(i - 1).reduce(0, +)
        let percentage = percentages[i - 1]
        
        let circleShape = CAShapeLayer()
        circleShape.path = circlePath.cgPath
        
        switch i-1 {
        case 0:
            circleShape.strokeColor = UIColor.red.cgColor
            
        case 1:
            circleShape.strokeColor = UIColor.green.cgColor
            
        case 2:
            circleShape.strokeColor = UIColor.blue.cgColor
            
        case 3:
            circleShape.strokeColor = UIColor.orange.cgColor
        default:
            circleShape.strokeColor = #colorLiteral(red: 0, green: 0, blue: 0, alpha: 1)
        }
        circleShape.fillColor = UIColor.clear.cgColor
        circleShape.lineWidth = width
        circleShape.strokeStart = CGFloat(prevPercentage)
        circleShape.strokeEnd = CGFloat(prevPercentage + percentage)
        view.layer.addSublayer(circleShape)
    }

结果:

---

我找不到

百分比的值与预期图像中的颜色之间的关系。
percentage
是否只是示例值？问题似乎在于计算开始和结束。用这种方法尝试，在循环外将
strokeStart
初始化为0，然后像
一样计算
strokeEnd
让strokeEnd=strokeStart+percentage-reducer
然后设置
circleShape.strokeStart=strokeStart circleShape.strokeEnd=strokeEnd
。最后在循环结束时，请设置
strokeStart=strokeEnd
无代码图片。此解决方案正是我所寻找的。