Image Slideshow Swift ios - ios

Question

I'm new to ios development. I am trying to make a simple fullscreen image slide show. On swipe left, the slideshow should show the next image, and swipe right the slideshow should show the previous image.
I have it working, however, if I swipe in quick succession, I get a blank screen, almost as if the animations aren't keeping up, and then when I wait a moment and swipe again the image views speed up into place and works normally again. Any idea what I'm doing wrong? What is the best practice when it comes to implementing an image carousel like this with a dynamic amount of images (here they're hardcoded)?
import UIKit
var imageArr = ["imageOne.jpg", "imageTwo.jpg", "imageThree.jpg", "imageFour.jpg", "imageFive.jpg"]
var imageIndex = 0;
class ViewController: UIViewController {
var currImage = UIImageView()
var rightImage = UIImageView()
var leftImage = UIImageView()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
var bounds:CGRect = UIScreen.mainScreen().bounds
var width:CGFloat = bounds.size.width
var height:CGFloat = bounds.size.height
currImage.frame = CGRect(x: 0.0, y: 0.0, width: width, height: height)
currImage.image = UIImage(named: imageArr[imageIndex])
rightImage.frame = CGRect(x: width, y: 0.0, width: width, height: height)
rightImage.image = UIImage(named: imageArr[imageIndex + 1])
leftImage.frame = CGRect(x: -width, y: 0.0, width: width, height: height)
leftImage.image = UIImage(named: imageArr[imageArr.count - 1])
self.view.addSubview(currImage)
self.view.addSubview(rightImage)
self.view.addSubview(leftImage)
var swipeLeft = UISwipeGestureRecognizer(target: self, action: "handleSwipe:")
swipeLeft.direction = UISwipeGestureRecognizerDirection.Left
self.view.addGestureRecognizer(swipeLeft)
var swipeRight = UISwipeGestureRecognizer(target: self, action: "handleSwipe:")
swipeRight.direction = UISwipeGestureRecognizerDirection.Right
self.view.addGestureRecognizer(swipeRight)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
let transitionManager = TransitionManager()
func handleSwipe(gesture: UIGestureRecognizer) {
var bounds:CGRect = UIScreen.mainScreen().bounds
var width:CGFloat = bounds.size.width
var height:CGFloat = bounds.size.height
if let swipeGesture = gesture as? UISwipeGestureRecognizer {
if (swipeGesture.direction == UISwipeGestureRecognizerDirection.Left ) {
UIView.animateWithDuration(0.5, delay: 0, usingSpringWithDamping: 0.8, initialSpringVelocity: 0.2, options: UIViewAnimationOptions.CurveEaseIn, animations: {
self.currImage.frame = CGRect(x: -width, y: 0.0, width: width, height: height)
self.rightImage.frame = CGRect(x: 0.0, y:0.0, width: width, height: height)
}, completion: { finished in
if (!finished) { return }
imageIndex++
imageIndex = imageIndex <= imageArr.count-1 ? imageIndex : 0
var leftIndex = imageIndex - 1 < 0 ? imageArr.count - 1 : imageIndex - 1
self.leftImage.image = UIImage(named: imageArr[leftIndex])
self.leftImage.frame = CGRect(x: -width, y: 0.0, width: width, height: height)
var tempImg = self.currImage
self.currImage = self.rightImage
self.rightImage = tempImg
self.rightImage.frame = CGRect(x: width, y: 0.0, width: width, height: height)
var rightIndex = imageIndex + 1 > imageArr.count - 1 ? 0 : imageIndex + 1
self.rightImage.image = UIImage(named: imageArr[rightIndex])
})
}
if (swipeGesture.direction == UISwipeGestureRecognizerDirection.Right) {
UIView.animateWithDuration(0.5, delay: 0, usingSpringWithDamping: 0.8, initialSpringVelocity: 0.2, options: UIViewAnimationOptions.CurveEaseIn, animations: {
self.currImage.frame = CGRect(x: width, y: 0.0, width: width, height: height)
self.leftImage.frame = CGRect(x: 0.0, y: 0.0, width: width, height: height)
}, completion: { finished in
imageIndex--
imageIndex = imageIndex < 0 ? imageArr.count - 1 : imageIndex
var rightIndex = imageIndex + 1 > imageArr.count - 1 ? 0 : imageIndex + 1
self.rightImage.image = UIImage(named: imageArr[rightIndex])
self.rightImage.frame = CGRect(x: width, y: 0.0, width: width, height: height)
var tempImg = self.currImage
self.currImage = self.tempImg
self.leftImage = tempCurr
self.leftImage.frame = CGRect(x: -width, y: 0.0, width: width, height: height)
var leftIndex = imageIndex - 1 < 0 ? imageArr.count - 1 : imageIndex - 1
self.leftImage.image = UIImage(named: imageArr[leftIndex])
})
}
}
}
}
Any help is much appreciated!

Answer 1

#IBOutlet weak var imageView:UIImageView!
var i=Int()
override func viewDidLoad() {
super.viewDidLoad()
Timer.scheduledTimer(timeInterval: 3.0, target: self, selector: #selector(imageChange), userInfo: nil, repeats: true)
// Do any additional setup after loading the view.
}
#objc func imageChange(){
self.imageView.image=images[i]
if i<images.count-1{
i+=1
}
else{
i=0
}
}

Answer 2

I have tried CollectionView for the carousel slideshow, but it didn't work out for me. I didn't like the hackish ways I had to do to make it show images in one row and I also didn't like the fact that it cannot return the active image (there is some workaround here as well, but they don't seem reliable). So, naturally, I ended up building a custom slideshow carousel for my purpose. I will share the code here, so hopefully, it can help(or at least guide someone) with a similar problem.
NOTE: My carousel is full width, singleImagePerScreen carousel, with a swipe recognizer to swipe through images and delegate function that is triggered when an image is active(I use it to display active image - "1 of 5").
TESTED ON: SWIFT 5, XCode 12.2, iOS 14.2
// ImageCarouselView class
import UIKit
class ImageCarouselView: UIView {
private let images: [UIImage?]
private var index = 0
private let screenWidth = UIScreen.main.bounds.width
var delegate: ImageCarouselViewDelegate?
lazy var previousImageView = imageView(image: nil, contentMode: .scaleAspectFit)
lazy var currentImageView = imageView(image: nil, contentMode: .scaleAspectFit)
lazy var nextImageView = imageView(image: nil, contentMode: .scaleAspectFit)
lazy var previousImageLeadingConstraint: NSLayoutConstraint = {
return previousImageView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: -screenWidth)
}()
lazy var currentImageLeadingConstraint: NSLayoutConstraint = {
return currentImageView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 0)
}()
lazy var nextImageLeadingConstraint: NSLayoutConstraint = {
return nextImageView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: screenWidth)
}()
init(_ images: [UIImage?]) {
self.images = images
super.init(frame: .zero)
self.translatesAutoresizingMaskIntoConstraints = false
setupLayout()
setupImages()
setupSwipeRecognizer()
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
private func setupLayout() {
self.subviews.forEach({ $0.removeFromSuperview() })
addSubview(previousImageView)
addSubview(currentImageView)
addSubview(nextImageView)
previousImageLeadingConstraint = previousImageView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: -screenWidth)
currentImageLeadingConstraint = currentImageView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 0)
nextImageLeadingConstraint = nextImageView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: screenWidth)
NSLayoutConstraint.activate([
previousImageLeadingConstraint,
previousImageView.centerYAnchor.constraint(equalTo: centerYAnchor),
previousImageView.widthAnchor.constraint(equalToConstant: screenWidth),
currentImageLeadingConstraint,
currentImageView.centerYAnchor.constraint(equalTo: centerYAnchor),
currentImageView.widthAnchor.constraint(equalToConstant: screenWidth),
nextImageLeadingConstraint,
nextImageView.centerYAnchor.constraint(equalTo: centerYAnchor),
nextImageView.widthAnchor.constraint(equalToConstant: screenWidth),
])
}
private func setupImages() {
currentImageView.image = images[self.index]
guard images.count > 1 else { return }
if (index == 0) {
previousImageView.image = images[images.count - 1]
nextImageView.image = images[index + 1]
}
if (index == (images.count - 1)) {
previousImageView.image = images[index - 1]
nextImageView.image = images[0]
}
}
private func setupSwipeRecognizer() {
guard images.count > 1 else { return }
let leftSwipe = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipes))
let rightSwipe = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipes))
leftSwipe.direction = .left
rightSwipe.direction = .right
self.addGestureRecognizer(leftSwipe)
self.addGestureRecognizer(rightSwipe)
}
#objc private func handleSwipes(_ sender: UISwipeGestureRecognizer) {
if (sender.direction == .left) {
showNextImage()
}
if (sender.direction == .right) {
showPreviousImage()
}
}
private func showPreviousImage() {
previousImageLeadingConstraint.constant = 0
currentImageLeadingConstraint.constant = screenWidth
UIView.animate(withDuration: 0.2, delay: 0.0, options: .curveEaseIn, animations: {
self.layoutIfNeeded()
}, completion: { _ in
self.nextImageView = self.currentImageView
self.currentImageView = self.previousImageView
self.previousImageView = self.imageView(image: nil, contentMode: .scaleAspectFit)
self.index = self.index == 0 ? self.images.count - 1 : self.index - 1
self.delegate?.imageCarouselView(self, didShowImageAt: self.index)
self.previousImageView.image = self.index == 0 ? self.images[self.images.count - 1] : self.images[self.index - 1]
self.setupLayout()
})
}
private func showNextImage() {
nextImageLeadingConstraint.constant = 0
currentImageLeadingConstraint.constant = -screenWidth
UIView.animate(withDuration: 0.2, delay: 0.0, options: .curveEaseIn, animations: {
self.layoutIfNeeded()
}, completion: { _ in
self.previousImageView = self.currentImageView
self.currentImageView = self.nextImageView
self.nextImageView = self.imageView(image: nil, contentMode: .scaleAspectFit)
self.index = self.index == (self.images.count - 1) ? 0 : self.index + 1
self.delegate?.imageCarouselView(self, didShowImageAt: self.index)
self.nextImageView.image = self.index == (self.images.count - 1) ? self.images[0] : self.images[self.index + 1]
self.setupLayout()
})
}
func imageView(image: UIImage? = nil, contentMode: UIImageView.ContentMode) -> UIImageView {
let view = UIImageView()
view.image = image
view.contentMode = contentMode
view.translatesAutoresizingMaskIntoConstraints = false
return view
}
}
// ImageCarouselViewDelegate
import UIKit
protocol ImageCarouselViewDelegate: NSObjectProtocol {
func imageCarouselView(_ imageCarouselView: ImageCarouselView, didShowImageAt index: Int)
}
// Usage
let slideshowView = ImageCarouselView(images) // initialize
self.slideshowView.delegate = self // set delegate in viewDidLoad()
extension YourViewController: ImageCarouselViewDelegate {
func imageCarouselView(_ imageCarouselView: ImageCarouselView, didShowImageAt index: Int) {
// do something with index
}
}

Answer 3

You can add collection view, add image in your custom collectionview cell, after that do checked Paging Enabled on props panel for collectionview. Use timer for auto slide