title: how to determine which cell's textfield was just edited in a collection view?
body: <p>What property can I access to find out?</p>
  
  <p>I was learning some swift from <a href="https://www.hackingwithswift.com/read/10/3/data-sources-and-delegates-uicollectionviewdatasource" rel="nofollow">this tutorial,</a> and I decided to give myself some problems to do. One was that in the tutorial, to edit a name, there is a <code>UIAlert</code>. I want to get rid of that and instead, have <code>UITextField</code> in place of the UILabel, so the user could simply tap on a name, and edit it. I would use the <code>textFieldDidEndEditing(textField: UITextField)</code> function to update the model, which is a dictionary of names and picture filenames.</p>
  
  <p>I set the view controller as the <code>UITextFieldDelegate</code>, I put in the function, but now I'm stuck, because although the text was updated just fine in one of the cells, I don't know how to tell which cell it happened in.</p>