title: Updating cell height after image downloads
body: <p>I am displaying some text and images in a <code>UITableView</code>. The image first gets downloaded. Since before the image gets downloaded, I don't know the size of image, so I initially put a <code>UIImageView</code> of some fixed size. And when the image is downloaded, I resize the <code>UIImageView</code>.  </p>
  
  <pre><code>dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
  
  // Download image
  
      dispatch_async(dispatch_get_main_queue(), ^{
  
      // UIImageView resizing  
      });  
  });
  </code></pre>
  
  <p>All this happens in <code>cellForRowAtIndexPath</code>.<br>
  The issues I am facing here are :<br>
  1. How do I update the height of cell ? Considering that there can be many images in a single cell. So I need to change the position of bottom image when above one downloads.<br>
  2. I tried using <code>UITableView</code> <code>beginUpdates</code> and <code>endUpdates</code>, but that scrolls to the top of cell giving a poor user experience.  </p>
  
  <p>This is how the UI looks like on reloadData. There are 5 images to be downloaded : <a href="https://youtu.be/8RRVOsRVy1o" rel="noreferrer"><strong>UI experience after UITableView reloadData</strong></a></p>