UICollectionView example in Swift

HeaderCollectionViewController.swift

class HeaderCollectionViewController: UIViewController, UICollectionViewDataSource, UICollectionViewDelegateFlowLayout, UICollectionViewDelegate {

    var collectionView : UICollectionView?

    override func viewDidLoad() {
        super.viewDidLoad()

        var layout = CSStickyHeaderFlowLayout()
        layout.parallaxHeaderReferenceSize = CGRectMake(... size of the header...)
        layout.minimumInteritemSpacing = 0
        layout.minimumLineSpacing = 0

        self.collectionView = UICollectionView(frame: UIScreen.mainScreen().bounds, collectionViewLayout: layout)
        self.collectionView!.registerClass(ShotPreviewCell.self, forCellWithReuseIdentifier: "shotPreview")
        self.collectionView!.delegate = self
        self.collectionView!.dataSource = self
        
        self.collectionView!.registerClass(ProfileViewHeader.self, forSupplementaryViewOfKind: CSStickyHeaderParallaxHeader, withReuseIdentifier: "ProfileViewHeader")

        self.view.addSubview(self.collectionView!)
    }

    func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return (self.shots != nil) ? self.shots!.count : 0
    }

    func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
        var cell = collectionView.dequeueReusableCellWithReuseIdentifier("shotPreview", forIndexPath: indexPath) as ShotPreviewCell
	// update cell
        return cell
    }
    
    func collectionView(collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, atIndexPath indexPath: NSIndexPath) -> UICollectionReusableView {
        if kind == CSStickyHeaderParallaxHeader {
            var headerView = collectionView.dequeueReusableSupplementaryViewOfKind(kind, withReuseIdentifier: "ProfileViewHeader", forIndexPath: indexPath) as ProfileViewHeader
            headerView.setup(self.user!)
            return headerView
        }
        return UICollectionReusableView()
    }


    func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize {
        let aspect: CGFloat = UIScreen.mainScreen().bounds.size.width / 3.0
        return CGSizeMake(shotWidth * aspect, shotHeight * aspect + 50)
    }

    func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
        var cell = collectionView.cellForItemAtIndexPath(indexPath) as ShotPreviewCell
        if (cell.image == nil) {
            return
        }
        // do something when selected
    }
}

Podfile

pod 'CSStickyHeaderFlowLayout'