use UIScrollView to show CarouselImagesView

Question

I have a UIScrollView can show a set of pages and have "carousel" effect, what I want is snap to an image after the user finishes dragging.Should I add some other func such like scrollViewDidEndDragging to observe user's action??? Thank you.

Code

    func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
        timer?.invalidate()

        scrolled(scrollView: scrollView)
    }

 private func scrolled(scrollView: UIScrollView) {
        guard let imageUrls = self.imageUrls else {
            return
        }

        if imageUrls.count < 1 {
            return
        }
.
        if abs(lastContentOffset - scrollView.contentOffset.x) < 50 {
            return
        }

        if lastContentOffset > scrollView.contentOffset.x {
            if currentPageIndex == 0 {
                currentPageIndex = imageUrls.count - 1
            } else {
                currentPageIndex -= 1
            }
        } else {
            if currentPageIndex < imageUrls.count - 1 {
                currentPageIndex += 1
            } else {
                currentPageIndex = 0
            }
        }

        layoutImages()

        self.delegate?.didChangePage(currentPageIndex)
    }

Answer 1

First of all scroll view are not reliable from memory point of view, in future if there are lots of images loaded dynamically your app may end up in memory flood situation and may crash.

Better use views like collection view, stack view or table view for cell reusability and it will also solve dragging problem.