IGListSupplementaryViewSource

Objective-C

@protocol IGListSupplementaryViewSource <NSObject>

Swift

protocol ListSupplementaryViewSource : NSObjectProtocol

Conform to this protocol to provide information about a list’s supplementary views. This data is used in IGListAdapter which then configures and maintains a UICollectionView. The supplementary API reflects that in UICollectionView, UICollectionViewLayout, and UICollectionViewDataSource.

-supportedElementKinds
Asks the SupplementaryViewSource for an array of supported element kinds.
Declaration
Objective-C

- (nonnull NSArray<NSString *> *)supportedElementKinds;
Swift

func supportedElementKinds() -> [String]
Return Value

An array of element kind strings that the supplementary source handles.


                    
                    
                    -viewForSupplementaryElementOfKind:atIndex:

Asks the SupplementaryViewSource for a configured supplementary view for the specified kind and index.

Note

This is your opportunity to do any supplementary view setup and configuration.

Warning

You should never allocate new views in this method. Instead deque a view from the IGListCollectionContext.

Declaration

Objective-C

- (nonnull __kindof UICollectionReusableView *)
    viewForSupplementaryElementOfKind:(nonnull NSString *)elementKind
                              atIndex:(NSInteger)index;

Swift

func viewForSupplementaryElement(ofKind elementKind: String, at index: Int) -> UICollectionReusableView

Parameters

`elementKind`	The kind of supplementary view being requested
`index`	The index for the supplementary veiw being requested.


                    
                    
                    -sizeForSupplementaryViewOfKind:atIndex:

Asks the SupplementaryViewSource for the size of a supplementary view for the given kind and index path.

Declaration

Objective-C

- (CGSize)sizeForSupplementaryViewOfKind:(nonnull NSString *)elementKind
                                 atIndex:(NSInteger)index;

Swift

func sizeForSupplementaryView(ofKind elementKind: String, at index: Int) -> CGSize

Parameters

`elementKind`	The kind of supplementary view.
`index`	The index of the requested view.

Return Value

The size for the supplementary view.