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Code: Select all

class CVCell: UICollectionViewCell, SelfConfiguringCell {
func configure(with item: Item) {
title.text = item.title
textView.backgroundColor = UIColor(item.backgroundColor)
textView.layer.borderColor = UIColor(item.borderColor).cgColor
titleImageView.image = UIImage(named: item.titleImage)
imageView.image = UIImage(named: item.image)
}
}

Code: Select all

class CVController: UIViewController, UICollectionViewDelegate {
var collectionView: UICollectionView!
var dataSource: UICollectionViewDiffableDataSource?
let sections = Bundle.main.decode([Section].self, from: "img1.json")

func createDataSource() {
dataSource = UICollectionViewDiffableDataSource(collectionView: collectionView) { collectionView, indexPath, item in
switch self.sections[indexPath.section].identifier {
case "carouselCell":
let cell = self.configure(CarouselCell.self, with: item, for: indexPath)
return cell
default: return self.configure(CarouselCell.self, with: item, for: indexPath)
}
}
}

func configure(_ cellType: T.Type, with item: Item, for indexPath: IndexPath) -> T {
guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellType.reuseIdentifier, for: indexPath) as? T else { fatalError("\(cellType)") }
cell.configure(with: item)
return cell
}

func reloadData() {
var snapshot = NSDiffableDataSourceSnapshot()
snapshot.appendSections(sections)
for section in sections { snapshot.appendItems(section.item, toSection: section) }
dataSource?.apply(snapshot)
}

func setupCollectionView() {
collectionView = UICollectionView(frame: view.bounds, collectionViewLayout: createCompositionalLayout())
collectionView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
collectionView.isScrollEnabled = false
collectionView.delegate = self
collectionView.contentInsetAdjustmentBehavior = .never
view.addSubview(collectionView)
collectionView.register(CarouselCell.self, forCellWithReuseIdentifier: CarouselCell.reuseIdentifier)

createDataSource()
reloadData()
}

func createCompositionalLayout() -> UICollectionViewLayout {
UICollectionViewCompositionalLayout { (sectionIndex: Int, layoutEnvironment: NSCollectionLayoutEnvironment) ->  NSCollectionLayoutSection? in

let itemSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1),   //
heightDimension: .fractionalHeight(1)) //
let item = NSCollectionLayoutItem(layoutSize: itemSize)

let groupWidth = (layoutEnvironment.container.contentSize.width * 1.05)/3
let groupSize = NSCollectionLayoutSize(widthDimension: .absolute(groupWidth),  //
heightDimension: .absolute(groupWidth)) //
let group = NSCollectionLayoutGroup.horizontal(layoutSize: groupSize, subitems: [item])

let section = NSCollectionLayoutSection(group: group)
section.contentInsets = NSDirectionalEdgeInsets(
top: (layoutEnvironment.container.contentSize.height/2) - (groupWidth/2),
leading: 0,
bottom: 0,
trailing: 0)
section.interGroupSpacing = 64
section.orthogonalScrollingBehavior = .groupPagingCentered
section.contentInsetsReference = .none
section.visibleItemsInvalidationHandler = { (items, offset, environment) in

items.forEach { item in
let distanceFromCenter = abs((item.frame.midX - offset.x) - environment.container.contentSize.width / 2.0)
let minScale: CGFloat = 0.7
let maxScale: CGFloat = 1.1
let scale = max(maxScale - (distanceFromCenter / environment.container.contentSize.width), minScale)
item.transform = CGAffineTransform(scaleX: scale, y: scale)
}
}

return section
}
}

func reloadItem(indexPath: IndexPath) {
guard let needReloadItem = dataSource!.itemIdentifier(for: indexPath) else { return }
var snapshot = NSDiffableDataSourceSnapshot()
snapshot.appendSections(sections)
for section in sections { snapshot.appendItems(section.item, toSection: section) }
dataSource?.apply(snapshot)
snapshot.reloadItems([needReloadItem])
dataSource?.apply(snapshot, animatingDifferences: false)
}

}

Code: Select all

func loadImageAsync(imageName: String, completion: @escaping (UIImage) -> ()) {
DispatchQueue.global(qos: .userInteractive).async {
guard let image = UIImage(named: imageName) else {return}
DispatchQueue.main.async {
completion(image)
}
}
}

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! RecipesViewCell

loadImageAsync(imageName: imageName) { (image) in
guard cell.imageName == imageName else { return }
cell.cardImageView.image = image
}
}

Code: Select all

class CVCell: UICollectionViewCell, SelfConfiguringCell {

func configure(with item: Item) {
loadImageAsync(imageName: item.image) { (image) in
self.imageView.image = image
}
}

func loadImageAsync(imageName: String, completion: @escaping (UIImage) -> ()) {
DispatchQueue.global(qos: .userInteractive).async {
guard let image = UIImage(named: imageName) else {return}
DispatchQueue.main.async {
completion(image)
}
}
}

}