swift - 垂直滚动（或 visibleItemsInvalidationHandler）使用 groupPagingCentered 重置正交部分的内部偏移量

Question

我用 groupPagingCentered 的正交部分做了 UICollectionViewCompositionalLayout 如下：

func neighborsRealitiesSection() -> NSCollectionLayoutSection {
  let itemSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1), heightDimension: .fractionalHeight(1))
  let item = NSCollectionLayoutItem(layoutSize: itemSize)
    
  let cellWidth = UIScreen.main.bounds.width / 3 + 1
  let groupSize = NSCollectionLayoutSize(widthDimension: .absolute(cellWidth), heightDimension: .absolute(cellWidth))
  let group = NSCollectionLayoutGroup.vertical(layoutSize: groupSize, subitems: [item])
    
  let section = NSCollectionLayoutSection(group: group)
  section.orthogonalScrollingBehavior = .groupPagingCentered
    
  section.visibleItemsInvalidationHandler = { items, offset, environment in
    items.filter { $0.representedElementKind != UICollectionView.elementKindSectionHeader }.forEach { item in
      let distanceFromCenter = abs((item.frame.midX - offset.x) - environment.container.contentSize.width / 2.0)
      let minScale: CGFloat = 0.7
      let maxScale: CGFloat = 1
      let scale = max(maxScale - (distanceFromCenter / environment.container.contentSize.width), minScale)
        
      item.transform = CGAffineTransform(scale: scale)
    }
  }
}

其他部分垂直滚动。垂直滚动时，正交偏移重置为零。如果我评论 visibleItemsInvalidationHandler，它不会被重置。

为什么会这样？有人有这个问题吗？