ios - swift:滚动collectionView

Question

我有 collectionView，我想在单击按钮时滚动到下一部分。如何做到这一点？

func numberOfSections(in collectionView: UICollectionView) -> Int {
        return 4  
    }

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return 3
    }

@IBAction func nextAction(_ sender: Any) {
        //scroll to next
    }

更新

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {

        cellOffset = 10

        cellWidth = (collectionView.bounds.width / 3)  - (cellOffset * 4)
        cellHeight = (cellWidth / 2 * 3) + (cellWidth / 2 * 0.65)

        return CGSize(width: cellWidth, height: cellHeight)
    }

Answer 1

这可以通过一些简单的步骤完成:

• 找到第一个当前可见部分的部分编号
• 如果节号不是最后一节，则加1

• 滚动到具有新节号的节

  let currentlyVisibleSection = collectionView.indexPathsForVisibleItems.map { $0.section }.min()!
  if currentlyVisibleSection < 3 {
      let scrollToSection = currentlyVisibleSection + 1
      collectionView.scrollToItem(at: IndexPath(item: 0, section: scrollToSection), at: .top, animated: true)
  
  }