class StretchyHeader: UICollectionViewFlowLayout {
override func layoutAttributesForElements(in rect: CGRect) -> [UICollectionViewLayoutAttributes]? {
let layoutAttributes = super.layoutAttributesForElements(in: rect)! as [UICollectionViewLayoutAttributes]
let contentOffset = collectionView!.contentOffset
if (contentOffset.y < 0) {
let deltaY = abs(contentOffset.y)
for attributes in layoutAttributes where attributes.representedElementKind == UICollectionView.elementKindSectionHeader {
var frame = attributes.frame
frame.size.height = headerReferenceSize.height + deltaY
frame.origin.y = frame.minY - deltaY
attributes.frame = frame
}
}
return layoutAttributes
}
override func shouldInvalidateLayout(forBoundsChange newBounds: CGRect) -> Bool {
return true
}
}
Trying to implement this to a compositional layout, but so far no good. How can I achieve this in a compositional layout?