Marks the specified supplementary views as invalid so that their layout information can be updated.
- macOS 10.11+
A string that identifies the type of the supplementary views. This parameter must not be
nilor an empty string.
A set of
NSIndexobjects. Each index path contains the section in which the supplementary view appears.
Call this method when you want the layout object to recompute attributes for one or more supplementary views. All of the views must be of the type specified by the
element parameter. The method adds the views you specify to the
invalidated property. You can call this method more than once for the specified