Swift中通过叠加UILabel实现混合进度条的方法

//// MixedColorProgressViewController.swift// Swift-Animations//// Created by YouXianMing on 16/8/21.// Copyright © 2016年 YouXianMing. All rights reserved.//import UIKitclass MixedColorProgressViewController: NormalTitleViewController {private var upView : UIView!private var upLabel : UILabel!private var downView : UIView!private var downLabel : UILabel!private var timer : GCDTimer! = GCDTimer(inQueue: GCDQueue.mainQueue)override func setup() {super.setup()downView = UIView(frame: CGRectMake(0, 0, 220, 17))downView.center = (contentView?.middlePoint)!downView.layer.cornerRadius = 2downView.backgroundColor = UIColor.whiteColor()downView.layer.masksToBounds = truecontentView?.addSubview(downView)downLabel = UILabel(frame: downView.bounds)downLabel.font = UIFont.HelveticaNeueThin(12.0)downLabel.text = "YouXianMing - iOS Programmer"downLabel.textColor = UIColor.redColor()downLabel.textAlignment = .CenterdownView.layer.borderWidth = 0.5downView.layer.borderColor = UIColor.redColor().CGColordownView.addSubview(downLabel)upView = UIView(frame: CGRectMake(0, 0, 220, 17))upView.center = (contentView?.middlePoint)!upView.layer.cornerRadius = 2upView.backgroundColor = UIColor.redColor()upView.layer.masksToBounds = truecontentView?.addSubview(upView)upLabel = UILabel(frame: upView.bounds)upLabel.font = UIFont.HelveticaNeueThin(12.0)upLabel.text = "YouXianMing - iOS Programmer"upLabel.textColor = UIColor.whiteColor()upLabel.textAlignment = .CenterupView.addSubview(upLabel)weak var wself = selftimer.event({UIView.animateWithDuration(0.5, delay: 0, usingSpringWithDamping: 3, initialSpringVelocity: 0, options: .CurveEaseInOut, animations: {wself?.upView.width = CGFloat(arc4random() % 220)}, completion: nil)}, timeIntervalWithSeconds: 1, delayWithSeconds: 1)timer.start()}}