title: Locate a specific content view in a UITableViewController using viewWithTag function
body: <p>I need to locate a specific content view in a table view.
  This table view is driven by a UITableViewController that is used to show my user with some parameters he can change in my app.
  For one of those cell, I need to programatically add a UITextView that I had subclass (NSTextStorage) to change text attribute, have rich text editing and so. 
  So I need to find that specific cell (content view) to by able to call my .addSubview. I thought this you be as simple as adding a specific tag to this view and call the .viewWithTag later in my viewDidLoad. The problem is a got a nil!?!</p>
  
  <p>Here's the little code snippet and a capture of my table hierarchy</p>
  
  <pre><code>override func viewDidLoad() {
      super.viewDidLoad()
  
      let specific = self.view.viewWithTag(99) //--&gt; Return nil
      let specific2 = self.tableView.viewWithTag(99) //--&gt; Also nil
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/jvEwN.png" alt="enter image description here">  </p>
  
  <p>What I'm doing wrong or did I miss something? This's my first shot at this method (viewWithTag) and maybe there's something else I need to do?</p>
  
  <p>Thx!</p>