swift版的CircleView

//
//  CircleView.swift
//  CircleView
//
//  Created by YouXianMing on 15/10/7.
//  Copyright © 2015年 YouXianMing. All rights reserved.
//

import UIKit

class CircleView: UIView {

// MARK: - 变量

var lineWidth  : CGFloat        = 1
var lineColor  : UIColor        = UIColor.blackColor()
var clockWise  : Bool           = false
var startAngle : CGFloat        = 0
var duration   : NSTimeInterval = 0.2

private var circleLayer : CAShapeLayer!

// MARK: - Public Method

/**
构建view,让参数生效
*/
func buildView() {

let size   = bounds.size
let point  = CGPoint(x: size.height / 2, y: size.width / 2)
let radius = size.width / 2 - lineWidth / 2

var tmpStartAngle : CGFloat = 0
var tmpEndAngle   : CGFloat = 0

if (clockWise == true) {

tmpStartAngle = -radian(Double(180 - startAngle));
tmpEndAngle   = radian(Double(180 + self.startAngle));

} else {

tmpStartAngle = radian(Double(180 - self.startAngle));
tmpEndAngle   = -radian(Double(180 + self.startAngle));
}

let circlePath = UIBezierPath(arcCenter: point, radius: radius, startAngle: tmpStartAngle, endAngle: tmpEndAngle, clockwise: clockWise)

circleLayer.path        = circlePath.CGPath
circleLayer.strokeColor = lineColor.CGColor
circleLayer.fillColor   = UIColor.clearColor().CGColor
circleLayer.lineWidth   = lineWidth
circleLayer.strokeEnd   = 0
}

/**
绘制圆形百分比

- parameter percent:  百分比
- parameter animated: 是否开启动画
*/
func changeToPercent(var percent : CGFloat, animated : Bool) {

if (percent <= 0) {

percent = 0;

} else if (percent >= 1) {

percent = 1;
}

if (animated) {

let basicAnimation : CABasicAnimation! = CABasicAnimation()
basicAnimation.keyPath                 = "strokeEnd"
basicAnimation.duration                = (duration <= 0 ? 0.2 : duration)
basicAnimation.fromValue               = circleLayer.strokeEnd
basicAnimation.toValue                 = percent
circleLayer.strokeEnd                  = percent
circleLayer.addAnimation(basicAnimation, forKey: nil)

} else {

CATransaction.setDisableActions(true)
circleLayer.strokeEnd = percent
CATransaction.setDisableActions(false)
}
}

// MARK: - System Method

override init(frame: CGRect) {

super.init(frame: frame)
createCircleLayer()
}

required init?(coder aDecoder: NSCoder) {

fatalError("init(coder:) has not been implemented")
}

// MARK: - Private Method

private func radian(degrees : Double) -> CGFloat {

return CGFloat((M_PI * degrees) / 180)
}

private func createCircleLayer() {

circleLayer       = CAShapeLayer()
circleLayer.frame = self.bounds
self.layer.addSublayer(circleLayer)
}
}

//
//  ViewController.swift
//  CircleView
//
//  Created by YouXianMing on 15/10/7.
//  Copyright © 2015年 YouXianMing. All rights reserved.
//

import UIKit

class ViewController: UIViewController {

var eventTimer : NSTimer!
var circleView : CircleView!

override func viewDidLoad() {
super.viewDidLoad()

eventTimer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: "timerEvent", userInfo: nil, repeats: true)

circleView            = CircleView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
circleView.lineWidth  = 1
circleView.lineColor  = UIColor.blackColor()
circleView.duration   = 0.25
circleView.clockWise  = true
circleView.startAngle = 90
circleView.center     = view.center
circleView.buildView()

view.addSubview(circleView)
}

func timerEvent() {

circleView.changeToPercent(CGFloat(arc4random() % 101) / 100, animated: true)
}
}