Scroll conflict for multiple CollectionView in a ViewController - ios

Question

I have two UICollectionView collectionViewA and collectionViewB in my ViewController, collectionViewB is presented as a subView when a button is tapped, the issue i have now is that when i scroll on collectionViewB, collectionViewA scrolls too, is there a way to only scroll for the active collectionView without affecting the second.?
extension TrendListVC: UICollectionViewDelegate,
UICollectionViewDataSource, UICollectionViewDelegateFlowLayout{
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
if collectionView == self.collectionViewForSubView{
return count
}
return 60
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
if collectionView == self.collectionViewForSubView{
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! ModalViewCell
//let setting = settings[indexPath.item]
//cell.setting = setting
return cell
}else{
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell2", for: indexPath) as! CollectionCell
cell.itemNameLabel.text = "Name".uppercased()
return cell
}
}
func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
var reusableView : CollectionHeader? = nil
if collectionView == self.collectionView{
if (kind == UICollectionElementKindSectionHeader) {
let head = collectionView.dequeueReusableSupplementaryView(ofKind: UICollectionElementKindSectionHeader, withReuseIdentifier: "headerCell", for: indexPath) as! CollectionHeader
head.trendListVc = self
head.headerHeightConstraint = headerHeightConstraint
reusableView = head
}
}
return reusableView!
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
if collectionView == self.collectionViewForSubView{
if count % 2 != 0 && indexPath.item == count - 1{
let paddingSpace = sectionInsets.left * (itemsPerRowForSubView + 1)
let availableWidth = collectionViewForSubView.frame.width - paddingSpace
return CGSize(width: availableWidth + 23, height: cellHeight)
}else{
let paddingSpace = sectionInsets.left * (itemsPerRowForSubView + 1)
let availableWidth = collectionViewForSubView.frame.width - paddingSpace
let widthPerItem = availableWidth / itemsPerRowForSubView
return CGSize(width: widthPerItem, height: cellHeight)
}
}else{
let paddingSpace = sectionInsets.left * (2 + 1)
let availableWidth = view.frame.width - paddingSpace
let widthPerItem = availableWidth / itemsPerRow
return CGSize(width: widthPerItem + 4, height: widthPerItem)
}
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
if collectionView == self.collectionView{
return CGSize(width: view.frame.width, height: 50)
}else{
return CGSize(width: 0, height: 0)
}
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
if collectionView == self.collectionView{
showControllerForSetting(setting: "Name")
}else if collectionView == self.collectionViewForSubView{
print("Some thing")
}
}
}

Answer 1

This is most likely due to using your ViewController as delegate and datasource for both of your collection views. You need to create separate delegate classes for each collection view.