title: how to override viewWillDisappear in Swift3
body: <p>I'm Trying to hide the first navigation bar and show all the others, so I used: </p>
  
  <pre><code>override func viewWillAppear(_ animated: Bool) {
      // Hide the navigation bar on the this view controller
      self.navigationController?.setNavigationBarHidden(true, animated: true)
  }
  
  override func viewWillDisappear(_ animated: Bool) {
      // Show the navigation bar on other view controllers
      self.navigationController?.setNavigationBarHidden(false, animated: true)
  }
  </code></pre>
  
  <p>what I need now is to call the super methods: <code>super.viewWillAppear(animated)</code> and <code>super.viewWillDisappear(animated)</code>, but I don't know where or how, any suggestions?</p>