UITableView - How to keep table rows fixed as user scrolls

Question

I\'d like to be able to fix the position of certain rows in a UITableView as the user scrolls.

Specifically, I have a table whereby certain rows are \"headers\" for

Answer 1

Swift 5 solution

var header: UIView?

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(indexPath: indexPath) as UITableViewCell
    header = cell.contentView
    return cell
}

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    let headerCell = tableView.cellForRow(at: IndexPath(row: 0, section: 0))
    guard headerCell == nil || (headerCell!.frame.origin.y < self.tableView.contentOffset.y + headerCell!.frame.height/2) else {
        header?.isHidden = true
        return
    }
    guard let hdr = header else { return }
    hdr.isHidden = false
    hdr.frame = CGRect(x: 0, y: tableView.contentOffset.y, width: hdr.frame.size.width, height: hdr.frame.size.height)
    if !tableView.subviews.contains(hdr) {
        tableView.addSubview(hdr)
    }
    tableView.bringSubviewToFront(hdr)
}