Uicollectionview Auto Scroll to Cell at Indexpath

UICollectionView auto scroll to cell at IndexPath

I've found that scrolling in viewWillAppear may not work reliably because the collection view hasn't finished it's layout yet; you may scroll to the wrong item.

I've also found that scrolling in viewDidAppear will cause a momentary flash of the unscrolled view to be visible.

And, if you scroll every time through viewDidLayoutSubviews, the user won't be able to manually scroll because some collection layouts cause subview layout every time you scroll.

Here's what I found works reliably:

Objective C :

- (void)viewDidLayoutSubviews {
    [super viewDidLayoutSubviews];

    // If we haven't done the initial scroll, do it once.
    if (!self.initialScrollDone) {
        self.initialScrollDone = YES;
    
        [self.collectionView scrollToItemAtIndexPath:self.myInitialIndexPath
                                    atScrollPosition:UICollectionViewScrollPositionRight animated:NO];
    }
}

Swift :

 override func viewWillLayoutSubviews() {

    super.viewWillLayoutSubviews()

      if !self.initialScrollDone {

         self.initialScrollDone = true
         self.testNameCollectionView.scrollToItem(at:selectedIndexPath, at: .centeredHorizontally, animated: true)
    }

}

How to automatically scrolling collectionviewcell to nearest cell(previous or next) when selecting a cell

You can just scroll to that indexPath on didSelectItemAt Method

var selectedIndex = 0

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "tabCell", for: indexPath) as! tabCollectionViewCell
    cell.tabLabel.text = self.tabArray[indexPath.item]
    if self.selectedIndex == indexpath.item {
        cell.bottomView.isHidden = false
    } else {
        cell.bottomView.isHidden = true
    }

    return cell
    }

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

    self.selectedIndex = indexpath.item
    self.tabCollectionView.reloadData()
    tabCollectionView.scrollToItem(at: indexPath, at: .centeredHorizontally, animated: true)
    }

Hope this Help!

How to scroll to a particluar index in collection view in swift

In viewDidLoad of your controller, you can write the code for scrolling to a particular index path of collection view.

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

CollectionView move to next cell automatically swift

Below is code you can try :

    /**
     Scroll to Next Cell
     */
    func scrollToNextCell(){

        //get Collection View Instance
        let collectionView:UICollectionView;

        //get cell size
        let cellSize = CGSizeMake(self.view.frame.width, self.view.frame.height);

        //get current content Offset of the Collection view
        let contentOffset = collectionView.contentOffset;

        //scroll to next cell
        collectionView.scrollRectToVisible(CGRectMake(contentOffset.x + cellSize.width, contentOffset.y, cellSize.width, cellSize.height), animated: true);

    }

    /**
     Invokes Timer to start Automatic Animation with repeat enabled
     */
    func startTimer() {

        let timer = NSTimer.scheduledTimerWithTimeInterval(1.0, target: self, selector: Selector("scrollToNextCell"), userInfo: nil, repeats: true);

    }

UICollectionView scroll to item not working with horizontal direction

For this part:

collectionView.scrollToItem(at: i, at: .top, animated: true)

When the scroll direction is horizontal you need to use at: left, at: right or at: centeredHorizontally. at: top is for vertical direction.

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