invalidateSupplementaryElements(ofKind:at:)
Adds the supplementary views at the specified index paths to the list of invalid items.
Declaration
func invalidateSupplementaryElements(ofKind elementKind: String, at indexPaths: [IndexPath])Parameters
- elementKind:
A string that identifies the type of the supplementary views. This parameter must not be
nil. - indexPaths:
An array of Nsindexpath objects. Each index path represents a supplementary view of the given kind whose layout needs to be recomputed.
Discussion
Call this method to identify the specific supplementary views of your layout that require updates. The views you specify are added to the dictionary in the invalidatedSupplementaryIndexPaths property. All of the views you specify should be of the type that you specified in the elementKind parameter. If you call this method two or more times with the same value for the elementKind parameter, this method merges the new index paths with the ones previously specified.