Type Property

invalidationContextClass

Returns the class to use when creating an invalidation context for the layout.

Declaration

class var invalidationContextClass: AnyClass { get }

Discussion

If you subclass UICollectionViewLayout and use a custom invalidation context object to improve the performance of your layout updates, override this method and return your UICollectionViewLayoutInvalidationContext subclass. When the collection view needs to invalidate your layout, it uses the class you provide to create an appropriate invalidation context object.

See Also

Invalidating the Layout

func invalidateLayout()

Invalidates the current layout and triggers a layout update.

func invalidateLayout(with: UICollectionViewLayoutInvalidationContext)

Invalidates the current layout using the information in the provided context object.

func shouldInvalidateLayout(forBoundsChange: CGRect) -> Bool

Asks the layout object if the new bounds require a layout update.

func invalidationContext(forBoundsChange: CGRect) -> UICollectionViewLayoutInvalidationContext

Returns a context object that defines the portions of the layout that should change when a bounds change occurs.