UICollectionViewCell programmatically
If you would like so as to add views to your cell, it’s best to use the init(body:) technique, and arrange your view hierarchy there. As a substitute of awakeFromNib it’s best to type your views within the init technique as properly. You may reset the whole lot inside the standard prepareForReuse technique. As you possibly can see by utilizing anchors generally it is value to ditch IB completely. 🎉
class Cell: UICollectionViewCell {
static var identifier: String = "Cell"
weak var textLabel: UILabel!
override init(body: CGRect) {
tremendous.init(body: body)
let textLabel = UILabel(body: .zero)
textLabel.translatesAutoresizingMaskIntoConstraints = false
contentView.addSubview(textLabel)
NSLayoutConstraint.activate([
contentView.centerXAnchor.constraint(equalTo: textLabel.centerXAnchor),
contentView.centerYAnchor.constraint(equalTo: textLabel.centerYAnchor),
])
self.textLabel = textLabel
reset()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been carried out")
}
override func prepareForReuse() {
tremendous.prepareForReuse()
reset()
}
func reset() {
textLabel.textAlignment = .heart
}
}UICollectionView programmatically
Creating assortment view controllers utilizing solely Swift code requires only some extra traces. You may implement loadView and create your UICollectionView object there. Retailer a weak reference of it contained in the controller, and the remaining is identical.
class ViewController: UIViewController {
weak var collectionView: UICollectionView!
var knowledge: [Int] = Array(0..<10)
override func loadView() {
tremendous.loadView()
let collectionView = UICollectionView(
body: .zero,
collectionViewLayout: UICollectionViewFlowLayout()
)
collectionView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(collectionView)
NSLayoutConstraint.activate([
view.topAnchor.constraint(equalTo: collectionView.topAnchor),
view.bottomAnchor.constraint(equalTo: collectionView.bottomAnchor),
view.leadingAnchor.constraint(equalTo: collectionView.leadingAnchor),
view.trailingAnchor.constraint(equalTo: collectionView.trailingAnchor),
])
collectionView = collectionView
}
override func viewDidLoad() {
tremendous.viewDidLoad()
collectionView.dataSource = self
collectionView.delegate = self
collectionView.register(Cell.self, forCellWithReuseIdentifier: Cell.identifier)
collectionView.alwaysBounceVertical = true
collectionView.backgroundColor = .white
}
}
extension ViewController: UICollectionViewDataSource {
func collectionView(
_ collectionView: UICollectionView,
numberOfItemsInSection part: Int
) -> Int {
knowledge.rely
}
func collectionView(
_ collectionView: UICollectionView,
cellForItemAt indexPath: IndexPath
) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(
withReuseIdentifier: Cell.identifier,
for: indexPath
) as! Cell
let knowledge = knowledge[indexPath.item]
cell.textLabel.textual content = String(knowledge)
return cell
}
}
extension ViewController: UICollectionViewDelegate {
func collectionView(
_ collectionView: UICollectionView,
didSelectItemAt indexPath: IndexPath
) {
}
}
extension ViewController: UICollectionViewDelegateFlowLayout {
func collectionView(
_ collectionView: UICollectionView,
structure collectionViewLayout: UICollectionViewLayout,
sizeForItemAt indexPath: IndexPath
) -> CGSize {
.init(width: collectionView.bounds.width, peak: 44)
}
func collectionView(
_ collectionView: UICollectionView,
structure collectionViewLayout: UICollectionViewLayout,
insetForSectionAt part: Int
) -> UIEdgeInsets {
.init(high: 0, left: 0, backside: 0, proper: 0)
}
func collectionView(
_ collectionView: UICollectionView,
structure collectionViewLayout: UICollectionViewLayout,
minimumInteritemSpacingForSectionAt part: Int
) -> CGFloat {
0
}
func collectionView(
_ collectionView: UICollectionView,
structure collectionViewLayout: UICollectionViewLayout,
minimumLineSpacingForSectionAt part: Int
) -> CGFloat {
0
}
}That was simple. Anchors are actually highly effective, Interface Builder is extraordinarily useful, however generally it is simply sooner to create your views from code. The selection is yours, however please do not be afraid of coding consumer interfaces! 😅
