Swift跑马灯效果

import UIKit
class CycleTitleView: UIView {
    private var lableArray:Array = []
    private lazy var lable  = UILabel()
    private lazy var nextLable = UILabel()
    private var timer:CADisplayLink?
    private var titleString:String?
    private let speed:CGFloat = 0.4
    override init(frame: CGRect) {
        super.init(frame: frame)
        self.addSubview(lable)
        self.addSubview(nextLable)
        self.layer.masksToBounds = true
        lable.textColor = UIColor.hexadecimalColor(hexadecimal: "#000000")
        lable.textAlignment = .center
        lable.font = UIFont.systemFont(ofSize: 32.f_pt)
        nextLable.textColor = UIColor.hexadecimalColor(hexadecimal: "#000000")
        nextLable.textAlignment = .center
        nextLable.font = UIFont.systemFont(ofSize: 32.f_pt)
    }
    func configerTitle(title:String?)  {
        if title == titleString {
            let size = lable .sizeThatFits(CGSize(width: CGFloat.greatestFiniteMagnitude, height: 10))
            let h = self.bounds.size.height
            lable.bounds = CGRect(x: 0, y: 0, width: size.width, height: h)
            nextLable.bounds = CGRect(x:0, y: 0, width: size.width, height: h)
            return
        }
        titleString = title
        invalidTimer()
        lable.text = title
        let size = lable .sizeThatFits(CGSize(width: CGFloat.greatestFiniteMagnitude, height: 10))
        let maxWidth = self.bounds.size.width
        let h = self.bounds.size.height
        lable.frame = CGRect(x: 0, y: 0, width: size.width, height: h)
        if size.width > maxWidth {
            self.addSubview(nextLable)
            creactTimer()
            nextLable.text = title
            nextLable.frame = CGRect(x: lable.frame.maxX + 10, y: 0, width: size.width, height: h)
        }else{
            nextLable.text = nil
            nextLable.removeFromSuperview()
        }
    }
    private func creactTimer(){
         invalidTimer()
        let safeObj = SafeObj(target: self, sel: #selector(ontimer))
        let disPlayLink =   CADisplayLink.init(target: safeObj, selector: safeObj.runTime)
        disPlayLink.add(to: RunLoop.main, forMode: .common)
        disPlayLink.isPaused = false
        timer = disPlayLink
    }
    @objc func ontimer(){
        lable.frame = CGRect(x: lable.frame.minX - speed, y: 0, width: lable.frame.width, height: lable.frame.height)
        nextLable.frame = CGRect(x: nextLable.frame.minX - speed, y: 0, width: nextLable.frame.width, height: nextLable.frame.height)
        if lable.frame.maxX < 0 {
            lable.frame = CGRect(x: nextLable.frame.maxX + 10, y: 0, width: lable.frame.width, height: lable.frame.height)
        }
        if nextLable.frame.maxX < 0 {
            nextLable.frame = CGRect(x: lable.frame.maxX + 10, y: 0, width: nextLable.frame.width, height: nextLable.frame.height)
        }
    }
    private func invalidTimer(){
            timer?.isPaused = true
            timer?.invalidate()
            timer = nil
    }
    override func layoutSubviews() {
        super.layoutSubviews()
        let height = self.bounds.height/2
        self.layer.cornerRadius  = height
        if lable.frame.height < height {
            configerTitle(title: titleString)
        }
    }
    deinit {
        invalidTimer()
    }
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}