选择单元格时 UICollectionView 正在滚动

Question

I'm having trouble when i try to select an item inside a UICollectionView since when I click on it it scrolls a little bit.

I know didSelectItemAtIndexPath is being called but I want to prevent the scrolling when selecting. I only want the collection view to scroll when the user is scrolling through but if the user is just tapping the cell it shouldn't move. Only should be selected.

I hope you can help me since I don't know how to prevent this problem.

Any help will be really appreciated.

Answer 1

If you are selecting the cell programmatically with collectionview.selectItem(at: indexpath, animated: true, scrollPosition: .top) -- and since you didn't share any of your code with us, let's assume that's correct...

... then like me you might not have realized that you can use an empty set like this: collectionview.selectItem(at: indexpath, animated: true, scrollPosition: [])

Answer 2

This can happen if you have paging enabled and the CollectionView is manually scrolled to a position that doesn't align with the expected page boundaries. When you select the cell, it adjusts to put the CollectionView at the correct page boundaries.

Answer 3

你可以试试这个：

collectionView.selectItem(at: newIdexPath, animated: true, scrollPosition: UICollectionViewScrollPosition(rawValue: 0))

Answer 4

In Swift 5 you can do

let indexPath = IndexPath(item: 10, section: 0)

self.collectionView.selectItem(at: indexPath, animated: false, scrollPosition: .init(rawValue: 0))

in viewDidAppear or viewDidLayoutSubviews

Answer 5

collectionView.selectItem(at: indexPath, animated: false, scrollPosition: [])

Answer 6

For Objective-C

[self.collectionView selectItemAtIndexPath:path animated:NO scrollPosition:UICollectionViewScrollPositionNone] 

For Swift

collectionview.selectItemAtIndexPath(indexPath: path, animated: false, scrollPosition: None)

Answer 7

swift 5

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {

        collectionView.scrollToItem(at: indexPath, at: .centeredHorizontally, animated: true)

}