ExampleCell + ExampleViewController

ExampleCell+ExampleViewController.swift

class ExampleCell: UICollectionViewCell, ReusableCell {
  func updateCellUI() {
    print("Here you should do something")
  }
}

class ExampleViewController: UIViewController {
  @IBOutlet weak var collectionView: UICollectionView!

  override func viewDidLoad() {
    collectionView.registerCell(ExampleCell)
  }
}

extension ExampleViewController: UICollectionViewDataSource {
  func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
    let cell: ExampleCell = collectionView.dequeueReusableCell(indexPath)
    cell.updateCellUI()
    return cell
  }
}