title: swift **willSelectRowAtIndexPath** enable and disable options
body: <p>I have Options such as:</p>
  
  <ol>
  <li>None</li>
  <li>Had once</li>
  <li>Every time</li>
  <li>SomeTime</li>
  </ol>
  
  <p>now if none is selected i want other options to be disabled and disable none if any of the options or all are selected.
  I have done</p>
  
  <pre><code>func tableView (tableView: UITableView, willSelectRowAtIndexPath indexPath: NSIndexPath) -&gt; NSIndexPath? {
  
      // first 3 rows in any section should not be selectable
      if indexPath.row &lt;= 1 {
          return nil
      }
  
      return indexPath
  }
  </code></pre>
  
  <p>This lets me to select only others except none. How can i achieve my requirements. Any ideas will be really appericiated. </p>
  
  <p>Thanks. </p>