title: How to change uitableviewcell's height after tableView.reloadData
body: <p>I am working on a twitter-like client, and there is a message list view implemented by UITableView.  For each cell, it may need to load a dynamic size image, and the image is loaded async. So it size of the image is unknown when the table view loaded. <br/></p>
  
  <p><strong>Is it possible to update the uitableviewcell's height after the image is loaded.</strong></p>
  
  <p>From my knowledge, the only way to update the height is in this method:
  - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
  But it is just called when loading data at first time. This is reasonable from performance consideration. Anyhow, is there a way to change the height later?</p>
  
  <p>Thanks for any information!</p>
  
  <p>Finally, I used "reloadRowsAtIndexPaths" to update particular rows, you can try this for hidden cells.  </p>
  
  <pre><code>[self.tableView beginUpdates];
  [self.tableView reloadRowsAtIndexPaths:toReloadRows withRowAnimation: UITableViewRowAnimationNone];
  [self.tableView endUpdates];
  </code></pre>
  
  <p>But, the cell shakes when updating the visible cells's height. So the it's better to have the cell height calculated before.</p>