Collection view inside a collection view - swift

Question

As of title, I'm having trouble with the issue of nesting collectionViews. I found a workaround gimmicky solution but I'm not really satisfied with the result:
class ViewController3: UIViewController, UICollectionViewDelegate, UICollectionViewDataSource {
#IBOutlet weak var outCollection: UICollectionView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
outCollection.dataSource = self
outCollection.delegate = self
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 5
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath:
IndexPath) -> UICollectionViewCell {
let cell = outCollection.dequeueReusableCell(withReuseIdentifier: "outCell", for:
indexPath) as! CollectionViewCell
cell.backgroundColor = .green
cell.setViewDD() // gimmick HERE
return cell
}
}
and for the CollectionViewCell
class CollectionViewCell: UICollectionViewCell, UICollectionViewDelegate, UICollectionViewDataSource {
#IBOutlet weak var inCollection: UICollectionView!
func setViewDD() {
self.inCollection.delegate = self
self.inCollection.dataSource = self
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 4
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = inCollection.dequeueReusableCell(withReuseIdentifier: "inCell", for: indexPath) as! innercellulosa
cell.backgroundColor = .red
return cell
}
}
if I try to set the delegate and datasource of the innerCollection (either in VC3 or CVCell) I stumble in multiple problems which I can't solve.