indexPathsToInsertForDecorationView(ofKind:)
Retrieves an array of index paths representing the decoration views to add.
Declaration
func indexPathsToInsertForDecorationView(ofKind elementKind: String) -> [IndexPath]Parameters
- elementKind:
The specific type of decoration view.
Return Value
An array of NSIndexPath objects indicating the location of the new decoration views or an empty array if you do not want to add any decoration views.
Discussion
The collection view calls this method whenever you add cells or sections to the collection view. Implementing this method gives your layout object an opportunity to add new decoration views to complement the additions.
The collection view calls this method between its calls to prepare(forCollectionViewUpdates:) and finalizeCollectionViewUpdates().
See Also
Responding to collection view updates
prepare(forCollectionViewUpdates:)finalizeCollectionViewUpdates()indexPathsToInsertForSupplementaryView(ofKind:)initialLayoutAttributesForAppearingItem(at:)initialLayoutAttributesForAppearingSupplementaryElement(ofKind:at:)initialLayoutAttributesForAppearingDecorationElement(ofKind:at:)indexPathsToDeleteForSupplementaryView(ofKind:)indexPathsToDeleteForDecorationView(ofKind:)finalLayoutAttributesForDisappearingItem(at:)finalLayoutAttributesForDisappearingSupplementaryElement(ofKind:at:)finalLayoutAttributesForDisappearingDecorationElement(ofKind:at:)targetIndexPath(forInteractivelyMovingItem:withPosition:)