title: Swift: How to animate the rowHeight of a UITableView?
body: <p>I'm trying to animate the height of tableViewCell rows by calling startAnimation() inside the tableView function:</p>
  
  <pre><code>func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -&gt; UITableViewCell {
  
      let cell = tableView.dequeueReusableCellWithIdentifier(cellIdentifier, forIndexPath: indexPath) as! TableViewCell
  
      tableView.rowHeight = 44.0
  
      startAnimation(tableView)
  
      return cell
  }
  
  //MARK: Animation function
  
  func startAnimation(tableView: UITableView) {
  
      UIView.animateWithDuration(0.7, delay: 1.0, options: .CurveEaseOut, animations: {
  
          tableView.rowHeight = 88.0
  
      }, completion: { finished in
  
          print("Row heights changed!")
      })
  }
  </code></pre>
  
  <p>The result: The row height does change but without any animation occurring. I don't understand why the animation doesn't work. Should I perhaps define some beginning and end state somewhere? </p>