ios - 使用 CAShapelayer 的循环计时器

试图为我的应用程序创建一个循环计时器最终得到这个

override func drawRect(rect: CGRect) {

    let context = UIGraphicsGetCurrentContext()

    let progressWidth: CGFloat = 10;

    let centerX = CGRectGetMidX(rect)
    let centerY = CGRectGetMidY(rect)
    let center: CGPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMidY(rect))
    let radius: CGFloat = rect.width / 2


    var circlePath = UIBezierPath(arcCenter: center, radius: radius, startAngle: CGFloat(0), endAngle:CGFloat(M_PI * 2), clockwise: true)
    let backgroundCircle = CAShapeLayer()




    backgroundCircle.path = circlePath.CGPath
    backgroundCircle.fillColor = backgroundCircleFillColor
    self.layer.addSublayer(backgroundCircle)

    circlePath = UIBezierPath(arcCenter: center, radius: radius-progressWidth/2, startAngle: -CGFloat(GLKMathDegreesToRadians(90)), endAngle:CGFloat(GLKMathDegreesToRadians(currentAngle)), clockwise: true)
    let progressCircle = CAShapeLayer()
    progressCircle.path = circlePath.CGPath
    progressCircle.lineWidth = progressWidth
    progressCircle.strokeColor = progressCircleStrokeColor
    progressCircle.fillColor = UIColor.clearColor().CGColor
    self.layer.addSublayer(progressCircle)


    let innerCirclePath = UIBezierPath(arcCenter: center, radius: radius-progressWidth, startAngle: CGFloat(0), endAngle:CGFloat(M_PI * 2), clockwise: true)

    let innerCircle = CAShapeLayer()
    innerCircle.path = innerCirclePath.CGPath
    innerCircle.fillColor = innerCircleFillColor

    self.layer.addSublayer(innerCircle)
}

列表项
这是我的代码的输出:

这段代码面临的主要问题是

画圆时手机发热

画了一半圆后下水速度降低

请帮我提供一个替代方案

最佳答案

试试这个 :

import UIKit

class CircularProgressBar: UIView {

    let shapeLayer       = CAShapeLayer()
    let secondShapeLayer = CAShapeLayer()
    var circularPath: UIBezierPath?

    override init(frame: CGRect) {
        super.init(frame: frame)
        print("Frame: \(self.frame)")
        makeCircle()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        makeCircle()
    }

    func makeCircle(){
        let circularPath = UIBezierPath(arcCenter: .zero, radius: self.bounds.width / 2, startAngle: 0, endAngle: 2 * CGFloat.pi, clockwise: true)
        shapeLayer.path = circularPath.cgPath
        shapeLayer.strokeColor = UIColor.orange.cgColor//UIColor.init(red: 0.0/255.0, green: 0.0/255.0, blue: 0.0/255.0, alpha: 1.0).cgColor
        shapeLayer.lineWidth = 5.0
        shapeLayer.fillColor = UIColor.clear.cgColor
        shapeLayer.lineCap = kCALineCapRound
        shapeLayer.strokeEnd = 0
        shapeLayer.position = self.center
        shapeLayer.transform = CATransform3DRotate(CATransform3DIdentity, -CGFloat.pi / 2, 0, 0, 1)
        self.layer.addSublayer(shapeLayer)

    }


    func showProgress(percent: Float){
        shapeLayer.strokeEnd = CGFloat(percent/100)
    }


}

在 UIView 中取一个 Storyboard 并将其添加为 subview 。然后你可以使用 showProgress 函数增加进度。

关于ios - 使用 CAShapelayer 的循环计时器，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/48656698/