title: How do you implement the UIAccessibility protocol?
body: <p>The "Accessibility Programming Guide For iOS" states:</p>
  
  <blockquote>
    <p>Another way is to implement the isAccessibilityElement method of the UIAccessibility protocol in the implementation of your custom subclass. The following code snippet shows how to do this:</p>
  </blockquote>
  
  <p>But when I am doing so, as in the following code:</p>
  
  <pre><code>class UITextLayerLabel : UIView, UIAccessibility {
  </code></pre>
  
  <p>XCode returns me this error:</p>
  
  <pre><code> [...] Use of undeclared type 'UIAccessibility'
  </code></pre>
  
  <p>What I am missing? A specific import? Is the protocol still available with iOS 10/XCode8?</p>