The UICollection​View​Controller class represents a view controller whose content consists of a collection view. It implements the following behavior:


  • If the collection view controller has an assigned nib file or was loaded from a storyboard, it loads its view from the corresponding nib file or storyboard. If you create the collection view controller programmatically, it automatically creates a new unconfigured collection view object, which you can access using the collection​View property.

  • When loading a collection view from a storyboard or nib file, the data source and delegate objects for the collection view are obtained from the nib file. If a data source or delegate is not specified, the collection view controller assigns itself to the unspecified role.

  • When the collection view is about to appear for the first time, the collection view controller reloads the collection view data. It also clears the current selection every time the view is displayed. You can change this behavior by setting the value of the clears​Selection​On​View​Will​Appear property to false.

You create a custom subclass of UICollection​View​Controller for each collection view that you want to manage. When you initialize the controller, using the init(collection​View​Layout:​) method, you specify the layout the collection view should have. Because the initially created collection view is without dimensions or content, the collection view’s data source and delegate—typically the collection view controller itself—must provide this information.

You may override the load​View() method or any other superclass method, but if you do, be sure to call super in the implementation of your method. If you do not, the collection view controller may not be able to perform all of the tasks needed to maintain the integrity of the collection view.


Initializing the UICollectionViewController Object

init(collection​View​Layout:​ UICollection​View​Layout)

Initializes a collection view controller and configures the collection view with the provided layout.

Getting the Collection View

var collection​View:​ UICollection​View?

The collection view object managed by this view controller.

var collection​View​Layout:​ UICollection​View​Layout

The layout object used to initialize the collection view controller.

Configuring the Collection View Behavior

var clears​Selection​On​View​Will​Appear:​ Bool

A Boolean value indicating if the controller clears the selection when the collection view appears.

var installs​Standard​Gesture​For​Interactive​Movement:​ Bool

A Boolean value indicating whether the collection view controller installs a standard gesture recognizer to drive the reordering process.

Integrating with a Navigation Controller

var use​Layout​To​Layout​Navigation​Transitions:​ Bool

A Boolean that indicates whether the collection view controller coordinates with a navigation controller for transitions.