title: iOS get default UISearchBar icon to set in UIButton
body: <p>Iam trying to get the default UISearchBar icon (Magnifying glass) to set in another UIButton.</p>
  
  <p>PS: I don't want to use a png downloaded from somewhere i want to use the default one.</p>
  
  <p>func to add the button with a custom image just to show some example:</p>
  
  <pre><code>func addRightNavigationButton(){
      let buttonBack: UIButton = UIButton.buttonWithType(UIButtonType.Custom) as! UIButton
      buttonBack.frame = CGRectMake(0, 0, 30, 33)
      buttonBack.setImage(UIImage(named:"search.png"), forState: UIControlState.Normal)
      buttonBack.addTarget(self, action: "barButtonItemClicked:", forControlEvents: UIControlEvents.TouchUpInside)
      var rightBarButtonItem: UIBarButtonItem = UIBarButtonItem(customView: buttonBack)
      self.navigationItem.setRightBarButtonItem(rightBarButtonItem, animated: false)
  }
  </code></pre>