How to get a UITableview to go to the top of page on reload?

Question

I am trying to get a UITableview to go to the top of the page when I reload the table data when I call the following from

- (void)pickerView:(UIPickerView *)pic         


        

Answer 1

You must scroll UITableView at the first row of your table view by using this line of code:

self.yourTableView.scrollToRow(at: IndexPath(row: 0, section: 0), at: .top, animated: true)

Answer 2

To scroll to a specific section you need to specify the index path to it:

NSIndexPath *topPath = [NSIndexPath indexPathForRow:0 inSection:0];
[TableView scrollToRowAtIndexPath:topPath
                 atScrollPosition:UITableViewScrollPositionTop
                         animated:YES];

If you are uncertain about the number of rows in your tableView. Use the following:

NSIndexPath *topPath = [NSIndexPath indexPathForRow:NSNotFound inSection:0];
[TableView scrollToRowAtIndexPath:topPath
                 atScrollPosition:UITableViewScrollPositionTop
                         animated:YES];

Answer 3

This is working for me.

tableView.scrollToRow(at: IndexPath.init(row: 0, section: 0), at: .top, animated: true)

Answer 4

After considering the options discussed above my version of the solutions is the following. It works consistently in iOS 11 & 12 for both UICollectionView & UITableView.

UICollectionView:

DispatchQueue.main.async { [weak self] in
    guard self?.<your model object>.first != nil else { return }

    self?.collectionView.scrollToItem(at: IndexPath(row: 0, section: 0),
                               at: .top,
                                     animated: false)
}

UITableView:

DispatchQueue.main.async { [weak self] in
    guard self?.<your model object>.first != nil else { return }

    self?.collectionView.scrollToRow(at: IndexPath(row: 0, section: 0),
                               at: .top,
                                     animated: false)
}

Answer 5

UITableView is a subclass of UIScrollView, so you can also use:

[mainTableView scrollRectToVisible:CGRectMake(0, 0, 1, 1) animated:YES];

Answer 6

For those still finding solution to this, you can use the following extension of UITableView.

Including a check where first section has row(s) or not. It goes till the section with row(s) comes and then scrolls to that one.

extension UITableView {

    func scrollToFirst() {

        self.reloadData() // if you don't want to reload data, remove this one.
        for i in 0..<self.numberOfSections {

            if self.numberOfRows(inSection: i) != 0 {

                self.scrollToRow(at: IndexPath(row: 0, section: i), at: .top, animated: true) 
                break 
            }
        }
    }
}

Hope that helped you.