Swift

Question

我有一个启用了分页的 collectionView：

collectionView.isPagingEnabled = true

collectionView 是全屏的（一次只显示 1 个单元格），我有一些代码在 scrollViewWillEndDragging 中运行。当我正常或半快速滚动时，cellForItem 和 scrollViewWillEndDragging 在同一个 page/indexPath.item 上。但是当我滚动得非常快时，它们都搞砸了，cellForItem 总是在当前页面后面

**如何防止用户在启用分页时快速滚动？

var currentItem: Int?

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeue...

    currentItem = indexPath.item

    return cell
}

func scrollViewWillEndDragging(_ scrollView: UIScrollView, withVelocity velocity: CGPoint, targetContentOffset: UnsafeMutablePointer<CGPoint>) {
    let yAxis = targetContentOffset.pointee.y
    let page = Int(yAxis / collectionView.frame.height)

    guard let currentItem = currentItem else { return }
    if page == currentItem {

        // only do something when page and the current indexPath.item are equal which works fine with normal scrolling
    }
}

Answer 1

这个answer有效：

func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {

    scrollView.isUserInteractionEnabled = false
}

func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {

    scrollView.isUserInteractionEnabled = true
}

Swift - 当 collectionView.isPagingEnabled = true 时防止快速滚动

Swift -prevent fast scrolling when collectionView.isPagingEnabled = true

uiscrollview

ios

uicollectionview