Ios 使用进度循环动画更新uilabel百分比

我有一个圆圈，它正在为自己制作动画。它被赋予一个介于0.01和1.0之间的数字，然后在一个圆中设置动画

<>我在它的中间有一个标签叫做“代码> PraseStRels<代码>。我希望标签随着圆圈的动画一起计数。因此，如果该值为0.12，则标签应显示12%

以下是“我的圆”动画的代码：

func animateView(toValue: Double, strokeColor: UIColor) {

        let screenWidth = self.view.frame.size.width
        let screenHeight = self.view.frame.size.height

        let circle = UIView(frame: CGRectMake((screenWidth / 2) - (150 / 2), (screenHeight / 2) - (150 / 2), 150, 150)) // viewProgress is a UIView
        circle.backgroundColor = UIColor.clearColor()
        view.addSubview(circle)

        var progressCircle = CAShapeLayer()
        var backgroundCircle = CAShapeLayer()
        progressCircle.frame = view.bounds
        backgroundCircle.frame = view.bounds

        let lineWidth:CGFloat = 20
        let rectFofOval = CGRectMake(lineWidth / 2, lineWidth / 2, circle.bounds.width - lineWidth, circle.bounds.height - lineWidth)

        let circlePath = UIBezierPath(ovalInRect: rectFofOval)

        progressCircle = CAShapeLayer ()
        progressCircle.path = circlePath.CGPath
        progressCircle.strokeColor = UIColor.whiteColor().CGColor
        progressCircle.fillColor = UIColor.clearColor().CGColor
        progressCircle.lineWidth = 20.0
        progressCircle.frame = view.bounds
        progressCircle.lineCap = "round"

        backgroundCircle = CAShapeLayer ()
        backgroundCircle.path = circlePath.CGPath
        backgroundCircle.strokeColor = strokeColor.CGColor
        backgroundCircle.fillColor = UIColor.clearColor().CGColor
        backgroundCircle.lineWidth = 20.0
        backgroundCircle.frame = view.bounds
        backgroundCircle.lineCap = "round"

        circle.layer.addSublayer(backgroundCircle)
        circle.layer.addSublayer(progressCircle)
        circle.transform = CGAffineTransformRotate(circle.transform, CGFloat(-M_PI_2))

        let animation = CABasicAnimation(keyPath: "strokeEnd")
        animation.fromValue = 0
        animation.toValue = toValue
        animation.duration = 1
        animation.fillMode = kCAFillModeForwards
        animation.removedOnCompletion = false
        animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseIn)

        progressCircle.addAnimation(animation, forKey: nil)
    }

我已经试过了，但是标签一直显示0.0%

var current: Double = 0.0

                let i = current * 100
                let max = 0.1 * 100


                if i < max {


                    self.progressLabel.text = "\(current)%"
                    current += 0.01 * 100
                }

var电流：双=0.0
设i=电流*100
设最大值=0.1*100
如果我

您应该检查表示层的值，以获取动画属性的当前值

func printValue() {
        let currentLayer = progressCircle.presentation()
        current = currentLayer?.value(forKeyPath: "strokeEnd") as? Float;
        print("current \(current)")

        let i = current! * 100
        let max:Float = 100


        if i < max {
            self.progressLabel.text = "\(current! * 100)%"
        }

    }

func printValue（）{
让currentLayer=progressCircle.presentation（）
current=currentLayer？值（forKeyPath:“strokeEnd”）为？浮点；
打印（“当前\（当前）”）
设i=电流！*100
设max:Float=100
如果我

---

调用方法printValue，无论您想在何处显示当前值，代码在此部分中断：

current=currentLayer？.valueForKey（“strokeEnd”）as！浮动