How to control which supplementary… | Apple Developer Forums

How to control which supplementary header views are invalidated in UICollectionView?

When scrolling a collection view, it looks like all supplementary views (even those that currently not appear) are invalidated. If there is a large number of supplementary views (section headers in my case) this significantly affects scrolling performance.

Can I instruct the collection view to invalidate only the visible supplementary header views (rather than all of them) when user scrolls the view?

Here is the code I use to create the collection view (tableview-like layout) in my custom UICollectionViewController class:

 // Create list layout configuration
UICollectionLayoutListConfiguration *config = [[UICollectionLayoutListConfiguration alloc] initWithAppearance:UICollectionLayoutListAppearancePlain];
config.headerMode = UICollectionLayoutListHeaderModeSupplementary;
 
// Create compositional layout based on configuration and assign to collection view
UICollectionViewCompositionalLayout *layout = [UICollectionViewCompositionalLayout layoutWithListConfiguration:config];
self.collectionView.collectionViewLayout = layout;

	// Create list layout configuration
	UICollectionLayoutListConfiguration *config = [[UICollectionLayoutListConfiguration alloc] initWithAppearance:UICollectionLayoutListAppearancePlain];
	config.headerMode = UICollectionLayoutListHeaderModeSupplementary;

	// Create compositional layout based on configuration and assign to collection view
	UICollectionViewCompositionalLayout *layout = [UICollectionViewCompositionalLayout layoutWithListConfiguration:config];
	self.collectionView.collectionViewLayout = layout;