layoutAttributesForSupplementaryView(ofKind:at:)
Returns the layout attributes of the supplementary view at the specified location in your layout.
Declaration
func layoutAttributesForSupplementaryView(ofKind elementKind: NSCollectionView.SupplementaryElementKind, at indexPath: IndexPath) -> NSCollectionViewLayoutAttributes?Parameters
- elementKind:
A string that identifies the type of the supplementary view. Use this string to differentiate the supplementary views in a given section.
- indexPath:
The index path of the supplementary view. Use this parameter to determine which section contains the supplementary view.
Return Value
A layout attributes object containing the layout information to apply to the supplementary view.
Discussion
If your layout includes supplementary views, you must override this method. In your implementation, create an instance of the appropriate layout attributes class and fill the resulting object with the layout information for the corresponding supplementary view. You define the supported supplementary views by assigning each one a string that identifies its kind. Use the elementKind and indexPath properties to identify the specific supplementary view whose attributes were requested.
You can call this method from other layout-related methods when you want to retrieve layout information for supplementary views. Call this method only for supplementary views. Do not call it to retrieve layout attributes for items or decoration views.
See Also
Providing Layout Information
layoutAttributesClassprepare()collectionViewContentSizelayoutAttributesForElements(in:)layoutAttributesForItem(at:)layoutAttributesForDecorationView(ofKind:at:)layoutAttributesForDropTarget(at:)layoutAttributesForInterItemGap(before:)targetContentOffset(forProposedContentOffset:)targetContentOffset(forProposedContentOffset:withScrollingVelocity:)