How to add PageControl inside UICollectionView Image Scrolling

Question

I have UICollectionView Horizontal Image listing codes. I want to add PageControl when scrolling images will shows, I added pagecontrol selector and IBOutlet but how can I integrate it between UICollecitonView?

My codes are below:

 class  ViewController: UIViewController,  UICollectionViewDelegate, UICollectionViewDataSource, UICollectionViewDelegateFlowLayout {


    @IBOutlet weak var View : DesignableView!


    @IBOutlet var collectionView: UICollectionView!
    @IBOutlet var collectionViewLayout: UICollectionViewFlowLayout!

    @IBOutlet open weak var pageControl: UIPageControl? {
        didSet {
            pageControl?.addTarget(self, action: #selector(ViewController.pageChanged(_:)), for: .valueChanged)
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()

         pageControl?.numberOfPages = 11


    }


    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return 11;
    }




    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell: ImageCollectionViewCell = collectionView.dequeueReusableCell(withReuseIdentifier: "ImageCollectionViewCell", for: indexPath) as! ImageCollectionViewCell
        cell.label.text = "Cell \(indexPath.row)"
        cell.backgroundImageView.image = UIImage(named: "Parallax \(indexPath.row + 1)")

        // Parallax cell setup
        cell.parallaxTheImageViewScrollOffset(self.collectionView.contentOffset, scrollDirection: self.collectionViewLayout.scrollDirection)
        return cell
    }



    @IBAction open func pageChanged(_ sender: UIPageControl) {

        print(sender.currentPage)


    }




    // MARK: Delegate

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
        return collectionView.bounds.size;
    }

    // MARK: Scrolling

    func scrollViewDidScroll(_ scrollView: UIScrollView) {
        // Parallax visible cells
        for cell: ImageCollectionViewCell in collectionView.visibleCells as! [ImageCollectionViewCell] {
            cell.parallaxTheImageViewScrollOffset(self.collectionView.contentOffset, scrollDirection: self.collectionViewLayout.scrollDirection)
        }
    }


    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }



}

Answer 1

I'm not a fan of the accepted answer. From time to time, willDisplay cell will return the wrong page for the page control depending on users interaction.

What I use:

func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
    pageControl.currentPage = Int(scrollView.contentOffset.x) / Int(scrollView.frame.width)
}

This will update the page after the user has finished scrolling thus making the currentPage of the pageControl more accurate.