How to make expandable UITableViewCell with UIStackView

Question

I had a problem with creating unfolding cells. I'm use a UIStackView. The problem is that when the cell is minimized, the lower view rides over the top and it turns out an ugly animation.

here is my methods

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    print("tap")
    self.tableView.beginUpdates()
    let cell = tableView.cellForRow(at: indexPath) as! TableViewCell
    cell.animate(duration: 0, c: {
        cell.stufView.layoutIfNeeded()
    })
    self.tableView.endUpdates()
}

and cell method animate

    func animate(duration:Double, c: @escaping () -> Void) {

        UIView.animateKeyframes(withDuration: duration, delay: 0, options: .calculationModePaced, animations: {
            UIView.addKeyframe(withRelativeStartTime: 0, relativeDuration: duration, animations: {

                self.stufView.isHidden = !self.stufView.isHidden
                if self.stufView.alpha == 1 {
                    self.stufView.alpha = 0.5
                } else {
                    self.stufView.alpha = 1
                }
            })

        }, completion: {  (finished: Bool) in
            print("animation complete")
            c()
        })
}

my storyboard