UICollectionViewCell with custom UICollectionViewLayout to create Parallax Animation On Just one subview - ios

Question

Inspired by this tutorial [Custom UICollectionViewLayout Tutorial With Parallax][1]
[1]: https://www.raywenderlich.com/527-custom-uicollectionviewlayout-tutorial-with-parallax I created my own version of parallax collection view.
I am creating the parallax animation and bounce affect on the header, and footer with this logic:
private func updateSupplementaryViews(_ type: Element, attributes: CustomLayoutAttributes, collectionView: UICollectionView, indexPath: IndexPath) {
if type == .header,
settings.isHeaderStretchy {
var delta: CGFloat = 0.0
let updatedHeight = min(
collectionView.frame.height + headerSize.height,
max(headerSize.height , headerSize.height - contentOffset.y))
let scaleFactor = updatedHeight / headerSize.height
if contentOffset.y <= 0{
delta = (updatedHeight - headerSize.height) / 2
}else{
delta = (headerSize.height - updatedHeight - abs(contentOffset.y))
}
let scale = CGAffineTransform(scaleX: scaleFactor, y: scaleFactor)
let translation = CGAffineTransform(translationX: 0, y: min(contentOffset.y, headerSize.height) + delta)
attributes.transform = scale.concatenating(translation)
}else if type == .footer,
settings.isFooterStretchy {
var updatedHeight: CGFloat = 0.0
if collectionView.contentSize.height - contentOffset.y < UIScreen.main.bounds.height {
updatedHeight = min(
collectionView.frame.height + footerSize.height,
max(footerSize.height, abs(((collectionView.contentSize.height - (footerSize.width + deviationDeviceSize)) - UIScreen.main.bounds.height) - contentOffset.y)))
}else{
updatedHeight = min(
collectionView.frame.height + footerSize.height,
max(headerSize.height, headerSize.height - contentOffset.y))
}
let scaleFactor = updatedHeight / footerSize.height
let delta = ((updatedHeight - footerSize.height) / 2) - footerSize.height
let scale = CGAffineTransform(scaleX: scaleFactor, y: scaleFactor)
let translation = CGAffineTransform(translationX: 0, y: min(contentOffset.y, footerSize.height) + delta )
attributes.transform = scale.concatenating(translation)
}
}
Everything works great beside the annoying fact that all my cell subviews are scaling with this animation and I would like to scale only my background image. This seems simple enough but unfortunately I couldn't figure out a way to control what subviews are being manipulated by the transformation.

Answer 1

What have you set as customAttributes for Element.footer ?
What is the footerSize you are setting ?
You have included some implementations around footer in your project which is not visible for us? Mind to share the whole file ?