我使用了这段代码让我的标签像跑马灯一样滚动：

@IBOutlet weak var firstLabel: UILabel! 
override func viewDidLoad() {
    super.viewDidLoad()

    UIView.animateWithDuration(12.0, delay: 1, options: ([.CurveLinear, .Repeat]), animations: {() -> Void in
            self.firstLabel.center = CGPointMake(0 - self.firstLabel.bounds.size.width / 2, self.firstLabel.center.y)
            }, completion:  { _ in })
}

是的，成功了。

更新为Swift 3，不使用任何第三方库或Pod

import UIKit

class ViewController: UIViewController {

    let redLabel: UILabel = {

        let label = UILabel()
        label.translatesAutoresizingMaskIntoConstraints = false
        label.font = .boldSystemFont(ofSize: 16)
        label.textColor = .red
        label.text = "The first paragraph of the body should contain the strongest argument, most significant example, cleverest illustration, or an obvious beginning point."
        return label
    }()

    let greenLabel: UILabel = {

        let label = UILabel()
        label.translatesAutoresizingMaskIntoConstraints = false
        label.font = .systemFont(ofSize: 14)
        label.textColor = .green
        label.text = "The second paragraph of the body should contain the second strongest argument, second most significant example, second cleverest illustration, or an obvious follow up the first paragraph in the body."
        return label
    }()

    override func viewDidLoad() {
        super.viewDidLoad()

        title = "Marquee Label Demo"
        view.backgroundColor = .white

        view.addSubview(redLabel)
        view.addSubview(greenLabel)

        setupAutoLayout()
        startMarqueeLabelAnimation()
    }

    func startMarqueeLabelAnimation() {

        DispatchQueue.main.async(execute: {

            UIView.animate(withDuration: 10.0, delay: 1, options: ([.curveLinear, .repeat]), animations: {() -> Void in

                self.redLabel.center = CGPoint(x: 0 - self.redLabel.bounds.size.width / 2, y: self.redLabel.center.y)
                self.greenLabel.center = CGPoint(x: 0 - self.greenLabel.bounds.size.width / 2, y: self.greenLabel.center.y)

            }, completion:  nil)
        })
    }

    func setupAutoLayout() {

        redLabel.leftAnchor.constraint(equalTo: view.rightAnchor).isActive = true
        redLabel.topAnchor.constraint(equalTo: view.topAnchor, constant: 100).isActive = true
        redLabel.heightAnchor.constraint(equalToConstant: 20).isActive = true

        greenLabel.leftAnchor.constraint(equalTo: view.rightAnchor).isActive = true
        greenLabel.topAnchor.constraint(equalTo: redLabel.bottomAnchor, constant: 50).isActive = true
        greenLabel.heightAnchor.constraint(equalToConstant: 20).isActive = true
    }
}

特别鸣谢：
https://stackoverflow.com/users/8303852/kartik-patel
https://stackoverflow.com/users/8388863/sid-patel
单击此处查看1演示

简单选框- Swift 4.0：

override func viewDidLoad() {
    super.viewDidLoad()
    marqueeLabel.text = " text text here!"
    _ = Timer.scheduledTimer(timeInterval: 0.3, target: self, selector: #selector(ViewController.marquee), userInfo: nil, repeats: true)
}
extension ViewController {
  @objc func marquee(){

    let str = marqueeLabel.text!
    let indexFirst = str.index(str.startIndex, offsetBy: 0)
    let indexSecond = str.index(str.startIndex, offsetBy: 1)
    marqueeLabel.text = String(str.suffix(from: indexSecond)) + String(str[indexFirst])

  }
}

在SWIFT 3中：

@IBOutlet weak var YOURLABEL: UILabel!
override func viewDidLoad() {
    super.viewDidLoad()
    UIView.animate(withDuration: 12.0, delay: 1, options: ([.curveLinear, .repeat]), animations: {() -> Void in
        self.YOURLABEL.center = CGPoint(x: 0 - self.YOURLABEL.bounds.size.width / 2, y: self.YOURLABEL.center.y)
    }, completion:  { _ in })
}

由于最初的问题与tvOS有关，我刚刚错误地发现（经过几周的搜索！）tvOS 12 beta已经实现了：

只有当祖先被聚焦时（比如当我们向电影海报添加标题并滚动到它时），才能获得字幕效果，当然，如果这是目标，可以直接从TVUIKit使用TVPosterView（比如this example），但它仍然适用于单个标签。

你应该像这样使用，然后它会工作。
注意：你可能会面临性能问题，因为它在线程中使用递归，所以为了更好的性能，你应该使用CATextLayer和CAScrollLayer。

import UIKit
import SnapKit

class ViewController: UIViewController {
    
    let label = UILabel()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        label.lineBreakMode = .byWordWrapping
        label.numberOfLines = 0
       
        label.text = "We couldn't turn around 'Til we were upside down I'll be the bad guy now But no, I ain't too proud I couldn't be there Even when I try You don't believe it We do this every time"
       
        view.addSubview(label)
        label.snp.makeConstraints { (make) in
           make.height.equalTo(20)
            make.top.leading.trailing.equalTo(self.view.safeAreaLayoutGuide).inset(50)
        }
      
        autoScroll()
    }
    
    @objc func autoScroll() {
        UIView.animate(withDuration: 12.0, delay: 1, options: ([.curveLinear, .repeat]), animations: {() -> Void in
            self.label.center = CGPoint(x: 0 - self.label.bounds.size.width / 2,y: self.label.center.y)
        }, completion:  { _ in
            self.autoScroll()
        })
    }
}

在Swift 4

代码

UIView.animate(withDuration: 1.0, delay: 1, options: ([.curveLinear, .repeat]), animations: {() -> Void in
            self.marqueeLABEL.center = CGPoint(x: self.marqueeLABEL.bounds.size.width, y: self.marqueeLABEL.center.y)
        }, completion:  { _ in })

在Swift 5.8中创建自定义视图。它对我起作用

import UIKit
import SnapKit

 final class AnimatedLabel: UIView {
   private var labelText: String {
    get {
        animatedLabel.text ?? ""
    } set {
        animatedLabel.text = newValue
    }
}

private var labelTextColor: UIColor {
    get {
        animatedLabel.textColor
    } set {
        animatedLabel.textColor = newValue
    }
}

private var labelTextFont: UIFont {
    get {
        animatedLabel.font
    } set {
        animatedLabel.font = newValue
    }
}

private var isTruncated: Bool {
    guard let labelText = animatedLabel.text else { return false }
    let labelTextSize = labelText.boundingRect(
        with: CGSize(
            width: animatedLabel.frame.size.width, height: .greatestFiniteMagnitude
        ),
        options: .usesLineFragmentOrigin,
        attributes: [.font: animatedLabel.font as Any],
        context: nil
    ).size
    return labelTextSize.height > animatedLabel.bounds.size.height
}

private var scrollView: UIScrollView = UIScrollView()
private var scrollTimer: Timer?
private var isScrollingToEnd = true

private lazy var cointainerView = UIView()

private lazy var animatedLabel: UILabel = {
    let label = UILabel()
    label.lineBreakMode = .byClipping
    label.textAlignment = .left
    return label
}()

override init(frame: CGRect) {
    super.init(frame: frame)
    setupUI()
}

required init?(coder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}

private func setupUI() {
    cointainerView.backgroundColor = .clear
    scrollView.backgroundColor = .clear
    scrollView.showsHorizontalScrollIndicator = false
    scrollView.isUserInteractionEnabled = false
    
    addSubview(cointainerView)
    cointainerView.addSubview(scrollView)
    scrollView.addSubview(animatedLabel)
    
    cointainerView.snp.makeConstraints {
        $0.left.right.top.bottom.equalToSuperview()
    }
    
    scrollView.snp.makeConstraints {
        $0.left.right.top.bottom.equalToSuperview()
    }
    
    animatedLabel.snp.makeConstraints {
        $0.top.bottom.left.right.equalToSuperview()
    }
    animatedLabel.sizeToFit()
    
    // Set the contentSize of the scrollView to enable scrolling
    scrollView.contentSize = CGSize(width: animatedLabel.bounds.width, height: animatedLabel.bounds.height)
    
    // Create a timer to scroll the label's content if isTruncated is true
    if !isTruncated {
        DispatchQueue.main.asyncAfter(deadline: .now() + 1) {
            self.scrollTimer = Timer.scheduledTimer(timeInterval: 0.03, target: self, selector: #selector(self.scrollLabel), userInfo: nil, repeats: true)
        }
    }
}

@objc private func scrollLabel() {
    if isScrollingToEnd {
        scrollView.contentOffset.x += 1.0
        if scrollView.contentOffset.x >= animatedLabel.bounds.width - scrollView.bounds.width {
            isScrollingToEnd = false
        }
    } else {
        scrollView.contentOffset.x -= 1.0
        if scrollView.contentOffset.x <= 0 {
            isScrollingToEnd = true
                self.scrollLabel()
            return
        }
    }
    // If the label has reached the end, reset the content offset to scroll from the beginning
    if scrollView.contentOffset.x >= animatedLabel.bounds.width - scrollView.bounds.width {
        scrollView.contentOffset.x = 0
    }
}

func configure(text: String, textColor: UIColor, font: UIFont) {
    labelText = text
    labelTextColor = textColor
    labelTextFont = font
}

}然后你的视图控制器

import UIKit

class ViewController: UIViewController {

var animatedLabel = AnimatedLabel()

override func viewDidLoad() {
    super.viewDidLoad()
    
    animatedLabel.configure(
        text: "In publishing and graphic design, is is a long text that will scroll like a marquee.",
        textColor: .black,
        font: .systemFont(ofSize: 18)
    )

    
    
    view.addSubview(animatedLabel)
    animatedLabel.translatesAutoresizingMaskIntoConstraints = false
    
    animatedLabel.topAnchor.constraint(equalTo: view.topAnchor, constant: 150).isActive = true
    animatedLabel.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20).isActive = true
    animatedLabel.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20).isActive = true
    animatedLabel.heightAnchor.constraint(equalToConstant: 40).isActive = true
    
    
  
}

}