func configureDiffableDataSource() {
    let dataSource = UICollectionViewDiffableDataSource<TripSection,TripItem>(collectionView: collectionView) {
        (collectionView: UICollectionView,indexPath: IndexPath,item: TripItem) -> UICollectionViewCell? in
      let cell = collectionView.dequeueCell(ofType: SmallTableViewCell.self,for: indexPath)
      cell.fillWithData(tip)
       return cell
        }
    }

/// ADD elementKindSectionHeader如果isFullScreen返回nil

    dataSource.supplementaryViewProvider = { [weak self] (collectionView: UICollectionView,kind: String,indexPath: IndexPath) -> UICollectionReusableView? iln
        guard let itamSequence = self?.dataSource?.itemIdentifier(for: indexPath) else { return nil }
        guard let section = self?.dataSource?.snapshot().sectionIdentifier(containingItem: itamSequence) else { return nil }
       let boardHeader = collectionView.dequeueReusableView(ofType: BoardSupplementaryView.self,forKind: UICollectionView.elementKindSectionHeader,for: indexPath)
         return boardHeader
        }
    }

     self.dataSource = dataSource
     updateSnapshot(animated: false)
}

生成布局时，可以传入索引

func generateLayout() -> UICollectionViewLayout {
    let layout = UICollectionViewCompositionalLayout {(sectionIndex: Int,layoutEnvironment: NSCollectionLayoutEnvironment) -> NSCollectionLayoutSection? in
        // do your layout stuff here. With sectionIndex,you can layout differently for each section
    }
    return layout
}

目前，除了创建自己的协议来确定是否应该在一个部分中显示标题之外，似乎没有其他方法可以做到这一点。幸运的是，UICollectionViewCompositionalLayout 构造函数为我们提供了部分索引，因此很容易做到。只需不要为没有它们的部分创建任何补充视图。

protocol CollectionViewLayoutProviderDelegate: class {
    func layoutProvider(_ provider: CollectionViewLayoutProvider,shouldDisplaySupplementaryViewIn section: Int) -> Bool
}

class CollectionViewLayoutProvider {
    weak var delegate: CollectionViewLayoutProviderDelegate?
    init(delegate: CollectionViewLayoutProviderDelegate?) {
        self.delegate = delegate
    }
    
    private func prepareSupplementaryViews(section: Int) -> [NSCollectionLayoutBoundarySupplementaryItem] {
        if let delegate = delegate,!delegate.layoutProvider(self,shouldDisplaySupplementaryViewIn: section) {
// Return empty array to avoid displaying headers

            return []
        }
        // Configure header if you need to
    }
    
    private func prepareSection(section: Int,group: NSCollectionLayoutGroup) -> NSCollectionLayoutSection {
        let layoutSection = NSCollectionLayoutSection(group: group)
        layoutSection.boundarySupplementaryItems = prepareSupplementaryViews(section: section)
        
        return layoutSection
    }
}

然后，在你的视图控制器中

private lazy var layoutProvider = CollectionViewLayoutProvider(delegate: self)

extension YouViewController: CollectionViewLayoutProviderDelegate {
    func layoutProvider(_ provider: CollectionViewLayoutProvider,shouldDisplaySupplementaryViewIn section: Int) -> Bool {
        return viewModel.shouldDisplayHeader(for: section) != nil
    }
}

我做什么：

uint64_t