How to set focus on collectionView in swift 4?

Question

Hello I have a UICollectionView. In a particular cell I have many views like UserProfileView, ProductView, CommentBoxView etc. In CommentBoxView there is a text view where the user can type and then post the comment. After posting the comment I want to focus that particular cell, from which cell user have posted the comment. For this I have used :

func indexPathForPreferredFocusedView(in collectionView: UICollectionView) -> IndexPath? {
  return IndexPath(row: 2, section: 0)
}

I am testing with the hardcoded value but still it is not coming. Please any one help me regarding this matter.

score 3 · Answer 1 · answered Jul 14 '18 at 14:17

3

Perhaps by "focus" you mean "scroll to." If you'd like to scroll to a cell, you should invoke

collectionView.scrollToItem(at: indexPath, scrollPosition: .centeredVertically, animated: true)

It may be useful to check out the documentation for this function.

As far as I know, while focus is a central concept in tvOS development, in iOS, its main function is to drive accessibility experiences. As such, I don't think it will have the effect you're expecting.

answered Jul 14 '18 at 14:17

woodcutting

271
1
9

where to write this code? after posting the comment? – Gorib Developer Jul 16 '18 at 05:13
sir how to pass indexPath in collectionView.scrollToItem(at: indexPath, scrollPosition: .centeredVertically, animated: true)? – Gorib Developer Jul 16 '18 at 05:28
Try something like `collectionView.scrollToItem(at: IndexPath(item: 2, section: 0), scrollPosition: .centeredVertically, animated: true)`. – woodcutting Jul 16 '18 at 12:52
@GoribDeveloper you need to write this code inside func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) method. – pulp Jun 17 '20 at 10:28

score 3 · Answer 2 · answered Jul 15 '18 at 06:14

3

Try to use:

self.collectionView.scrollToItem(at:IndexPath(item: indexNumber, section: sectionNumber), at: .right, animated: false)

answered Jul 15 '18 at 06:14

shiju86.v

667
5
10

where to write this code? after posting the comment? – Gorib Developer Jul 16 '18 at 05:13
sir how to pass indexPath in collectionView.scrollToItem(at: indexPath, scrollPosition: .centeredVertically, animated: true)? – Gorib Developer Jul 16 '18 at 05:28
sure sir i will – Gorib Developer Jul 17 '18 at 10:05
actually sir i have a collectionView. In a particular cell I have many views like UserProfileView, ProductView, CommentBoxView etc. In CommentBoxView there is a textView where the user can type and then post the comment. After posting the comment I want to scroll that particular cell, from which cell user have posted the comment. I know that I have to use self.collectionView.scrollToItem(at:IndexPath(item: indexNumber, section: sectionNumber), at: .right, animated: false) – Gorib Developer Jul 17 '18 at 10:06
but it is not running – Gorib Developer Jul 17 '18 at 10:06
UserProfileView, ProductView, CommentBoxView etc these all are made in a different cell? – shiju86.v Jul 17 '18 at 10:08
i m using custom delegate for posting comment – Gorib Developer Jul 17 '18 at 10:09
you should use a different cell for this. Then you can identify which cell you need to focus or move to the selected index. – shiju86.v Jul 17 '18 at 10:10
Using one cell, you can notify your CommentBoxView/ProductView etc. rest you need to do research on this. – shiju86.v Jul 17 '18 at 10:13

How to set focus on collectionView in swift 4?

2 Answers2