Why does my UITableView “jump” when inserting or removing a row?

Question

(Happy to accept an answer in Swift or Objective-C)

My table view has a few sections, and when a button is pressed, I want to insert a row at the end of section 0.

Answer 1

Save estimated row heights

    private var cellHeight = [Int:CGFloat]()
    override func tableView(_ tableView: UITableView, didEndDisplaying cell: UITableViewCell, forRowAt indexPath: IndexPath) {
        cellHeight[indexPath.row] = cell.frame.self.height
    }
    override func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {
    if let height = cellHeight[indexPath.row] {
        return height
    }
    return tableView.estimatedRowHeight

Fix scroll origin Y

    let indexPath = IndexPath(row: INDEX, section: 0)
    tableView.beginUpdates()
    tableView.insertRows(at: [indexPath], with: .fade)
    tableView.endUpdates()
    tableView.setContentOffset(tableView.contentOffset, animated: false)