An advanced tutorial on how to customize UICollectionView with advanced and smooth parallax effects.
A key entity associated with UICollectionView is the UICollectionViewLayout. The UICollectionViewLayout object is responsible for defining the attributes of all the elements of a collection view such as cells, supplementary views and decoration views.
UIKit offers a default implementation of UICollectionViewLayout called UICollectionViewFlowLayout. This class lets you set up a grid layout with some elementary customizations.
This UICollectionViewLayout tutorial will teach you how to subclass and customize the UICollectionViewLayout class. It will also show you how to add custom supplementary views, stretchy, sticky and parallax effects to a collection view.
Continue on raywenderlich.com