ios - UICollectionViewCompositionalLayout 不会滚动到不完整的组

Question

我有简单的实现UICollectionViewCompositionalLayout。有两个部分，每个部分都有水平滚动的单行，部分中的每个项目都有整个容器的 1/4 宽度（现在是全屏）。

我想要分页滚动，但是当数据源在该部分提供4n+1 个元素时，我无法滚动访问最后一项。

如何使用简单的最后一项的纯动画来修复它UICollectionViewFlowLayout？

func createCollectionViewLayout() -> UICollectionViewLayout {
    UICollectionViewCompositionalLayout { sectionIndex, environment -> NSCollectionLayoutSection? in
        let itemSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1 / 4), heightDimension: .fractionalHeight(1))
        let item = NSCollectionLayoutItem(layoutSize: itemSize)

        let groupSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1), heightDimension: .fractionalWidth(0.4))
        let group = NSCollectionLayoutGroup.horizontal(layoutSize: groupSize, subitem: item, count: 4)

        let headerSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1), heightDimension: .absolute(44))
        let header = NSCollectionLayoutBoundarySupplementaryItem(layoutSize: headerSize, elementKind: UICollectionView.elementKindSectionHeader, alignment: .top)

        let section = NSCollectionLayoutSection(group: group)
        section.orthogonalScrollingBehavior = .groupPaging
        section.boundarySupplementaryItems = [header]

        return section
    }
}

带有错误示例的视频

标签： iosswiftuicollectionviewuicollectionviewcompositionallayout

Answer 1

经过复杂的研究：似乎是布局错误，一种可能的解决方案是以编程方式更改orthogonalScrollingBehavior取决于项目的数量