I have attached the full reproducible example below.

I am using a list version of UICollectionViewCompositionalLayout in a SwiftUI app.

When scrolling, it crashes the app with an error: “Fatal error: <UICollectionView 0x600000ca2c70> is stuck in a recursive layout loop. This can happen when self-sizing views do not return consistent sizes, or the collection view’s frame/bounds/contentOffset is being constantly adjusted.”

I am not entirely sure on how to debug this.

Once I remove, “collectionView.contentInsetAdjustmentBehavior = .never”, the collection view list compositional layout scrolls smoothly. Replacing UIHostingConfiguration with UIKit cells also fixes the problem.

struct ContentView: View {
    var body: some View {
        GeometryReader { geo in
            ViewRepresentable()
        }
        .ignoresSafeArea(edges: .top)
    }
}

struct ViewRepresentable: UIViewControllerRepresentable {
    func makeUIViewController(context: Context) -> UIViewController {
        ViewController()
    }
    
    func updateUIViewController(_ uiViewController: UIViewController, context: Context) {
        
    }
}

struct Item: Hashable {
    var id = UUID()
    let name: String
}

class ViewController: UIViewController {
    enum Section: CaseIterable {
        case main
    }
    
    enum ListItem: Hashable {
        case header
        case item(Item)
    }
    
    let testItems: [Item] = (1...100).map { Item(name: "Item ($0)") }

    var collectionView: UICollectionView!
    var dataSource: UICollectionViewDiffableDataSource<Section, ListItem>!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        collectionView = UICollectionView(frame: .zero, collectionViewLayout: createLayout())
        collectionView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: 60, right: 0)

        collectionView.contentInsetAdjustmentBehavior = .never //Completely breaks scrolling for UIHostingConfiguration
        collectionView.delaysContentTouches = false
        collectionView.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(collectionView)

        NSLayoutConstraint.activate([
            collectionView.topAnchor.constraint(equalTo: view.topAnchor),
            collectionView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            collectionView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            collectionView.bottomAnchor.constraint(equalTo: view.bottomAnchor)
        ])

        configureDataSource()
        applySnapshot()
    }
    
    func createLayout() -> UICollectionViewLayout {
        var listConfiguration = UICollectionLayoutListConfiguration(appearance: .plain)
        listConfiguration.headerMode = .firstItemInSection
        listConfiguration.headerTopPadding = 0

        let layout = UICollectionViewCompositionalLayout.list(using: listConfiguration)
        return layout
    }

    func configureDataSource() {
        let headerCellRegistration = UICollectionView.CellRegistration<UICollectionViewListCell, ListItem> { (header, indexPath, item) in
            
            let view = Color.blue.frame(width: 300, height: 300)
            let controller = UIHostingController(rootView: view)
            controller.safeAreaRegions = SafeAreaRegions()
            header.addSubview(controller.view)

            controller.view.translatesAutoresizingMaskIntoConstraints = false

            NSLayoutConstraint.activate([
                controller.view.centerXAnchor.constraint(equalTo: header.centerXAnchor),
                controller.view.topAnchor.constraint(equalTo: header.topAnchor),
                controller.view.bottomAnchor.constraint(equalTo: header.bottomAnchor),
            ])
        }
        
        let itemCellRegistration = UICollectionView.CellRegistration<UICollectionViewListCell, ListItem> {
            [unowned self] (cell, indexPath, item) in
            
            let indexPathEdited = IndexPath(row: indexPath.row - 1, section: 0)
            let item = testItems[indexPathEdited.row]
            cell.contentConfiguration = UIHostingConfiguration {
                Text(item.name)
                    .frame(height: 50)
            }
        }
        
        dataSource = UICollectionViewDiffableDataSource<Section, ListItem>(collectionView: collectionView) { collectionView, indexPath, listItem in
            switch listItem {
            case .header:
                return collectionView.dequeueConfiguredReusableCell(using: headerCellRegistration, for: indexPath, item: listItem)
            case .item:
                return collectionView.dequeueConfiguredReusableCell(using: itemCellRegistration, for: indexPath, item: listItem)
            }
        }
    }

    func applySnapshot() {
        var snapshot = NSDiffableDataSourceSnapshot<Section, ListItem>()
        snapshot.appendSections([.main])
                        
        snapshot.appendItems([ListItem.header])
                
        var listItems: [ListItem] = []
        for item in testItems {
            listItems.append(ListItem.item(item))
        }
        
        snapshot.appendItems(listItems)
        dataSource.apply(snapshot, animatingDifferences: false)
    }
}