在Swift中获取Visible IndexPath UICollectionView

Question

如何获得visible IndexPath,而scrolling在collectionView我提到的许多链接1,链接2但是indexPathForCell在斯威夫特不支持.

Answer 1

你试过代理功能吗？

public func indexPathsForVisibleItems() -> [NSIndexPath]

要么

collectionView.indexPathsForVisibleItems()

这些必须给你你想要的.

Answer 2

试试这个

代表

func scrollViewDidEndDecelerating(scrollView: UIScrollView) {
for cell in yourCollectionViewname.visibleCells()  as [UICollectionViewCell]    {
   let indexPath = yourCollectionViewname.indexPathForCell(cell as UICollectionViewCell)

    NSLog("%@", indexPath)
}
}

选择-2

按钮单击

  var point : CGPoint = sender.convertPoint(CGPointZero, toView:yourCollectionViewname)
var indexPath =yourCollectionViewname!.indexPathForItemAtPoint(point)

获取所有项目

你可以使用indexPathsForVisibleRows

返回索引路径数组,每个索引路径标识接收器中的可见行.

• (NSArray*)indexPathsForVisibleItems;

var visible: [AnyObject] = yourCollectionViewname.indexPathsForVisibleItems
var indexpath: NSIndexPath = (visible[0] as! NSIndexPath)

Answer 3

This will work fine.

func scrollViewWillEndDragging(_ scrollView: UIScrollView, withVelocity velocity: CGPoint, targetContentOffset: UnsafeMutablePointer<CGPoint>) {

    let visibleIndex = Int(targetContentOffset.pointee.x / collectionView.frame.width)
    print(visibleIndex)

}

Answer 4

快速，安全的方式获得可见的物品：

if let indexPaths = self.collectionView.indexPathsForVisibleItems {
    //Do something with an indexPaths array.
}