import UIKit

class ViewController: UIViewController {

    @IBOutlet weak var scrollView: UIScrollView!

    @IBOutlet weak var pageControll: UIPageControl!
    var imageViews = [UIImageView]()

    override func viewDidLoad() {

        super.viewDidLoad()
        scrollView.delegate = self
        pageControll.currentPage = 0
        let imagesNames = ["1","2","3"]
        pageControll.numberOfPages = imagesNames.count

        for name in imagesNames  {
            let image = UIImage(named: name)
            let imageView = UIImageView(image: image)
            imageView.contentMode = .scaleAspectFit
            scrollView.addSubview(imageView)
            imageViews.append(imageView)


        }
    }

    override func viewDidLayoutSubviews() {
        super.viewDidLayoutSubviews()

        for (index, imageView) in imageViews.enumerated() {
            imageView.frame.size = scrollView.frame.size
            imageView.frame.origin.x = scrollView.frame.width * CGFloat(index)
            imageView.frame.origin.y = 0
        }

        let contentWidth = scrollView.frame.width * CGFloat(imageViews.count)
        scrollView.contentSize = CGSize(width: contentWidth, height: scrollView.frame.height)

    }





        // Do any additional setup after loading the view.
    }


extension ViewController: UIScrollViewDelegate {
    func scrollViewDidScroll(_ scrollView: UIScrollView) {
        let pageIndex = (scrollView.contentOffset.x / scrollView.frame.width)
        let roundedPageIndex = Int(pageIndex.rounded())
        pageControll.currentPage = roundedPageIndex
    }
}