title: How to go "without navigation bar view controller" to "with navigation bar view controller" in Swift
body: <p>I have project and it has many <code>view controllers</code> , e.g. <code>StartViewController</code> (<strong>Has Navigation Bar</strong>). Also <code>processViewController</code> and <code>processViewController</code> has many <code>views</code> and <code>processViewController</code> <strong>doesn't have Navigation Bar</strong> .</p>
  
  <p>processViewController has <code>Close button</code> and action with;</p>
  
  <pre><code>@IBAction func goStart(sender: UIButton) {
      let secondViewController = self.storyboard?.instantiateViewControllerWithIdentifier("StartViewController") as! StartViewController
      self.navigationController?.pushViewController(secondViewController, animated: true)
  }
  </code></pre>
  
  <p>When I push it then;</p>
  
  <pre><code>navigationController!.navigationBar.barTintColor = UIColorFromRGBs(0x000000)
  navigationController!.navigationBar.tintColor = UIColor.whiteColor();
  
  let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 164, height: 38))
  imageView.contentMode = .ScaleAspectFit
  let image = UIImage(named: "logo")
  imageView.image = image
  navigationItem.titleView = imageView
  </code></pre>
  
  <p>Those lines give error.</p>
  
  <p>How can I fix it ? How can I go from without navigation bar view controller to with navigation bar view controller?</p>