title: iOS: reload single cell of UICollectionView
body: <p>I am trying to follow the following post on reload a cell in a UICollectionView:</p>
  
  <p><a href="https://stackoverflow.com/questions/20296929/uicollectionview-update-a-single-cell">UICollectionView update a single cell</a></p>
  
  <p>I know that I ultimately want something that looks like this:</p>
  
  <pre><code>[self.collectionView reloadItemsAtIndexPaths:??];
  </code></pre>
  
  <p>But I don't know how to find and pass the indexPath of a particular cell.  Can anyone provide any pointers?</p>
  
  <p>I have an NSMutableArray that contains all the cell information (imageViews that are generated in each cell).  Ideally, what I'd like to do is pass the index of the NSMutableArray to refresh the corresponding cell on the page.  But I'm not sure how the numerical index gets translated into an indexPath.</p>
  
  <p>Thanks in advance for your help!</p>