title: Present view controller while current view controller has a UITabBar but no UITabBarController
body: <p>I have a <code>UIViewController</code> with a <code>UITabBar</code> at top of it. I am not using a <code>UITabBarController</code> because I need the <code>UITabBar</code> at the top and not at the bottom of the view. Here is my current view controller :</p>
  
  <pre><code>class CustomTabBarController: UIViewController, UITabBarDelegate
  {
      @IBOutlet weak var tabBar: UITabBar!
      var viewControllers: [UIViewController] = []
  
      //MARK: UIVIewController delegate
      override func viewDidLoad()
      {
          super.viewDidLoad()
  
          //TabBarController
          let storyboard = UIStoryboard(name: "Main", bundle: nil)
  
          self.viewControllers.append(storyboard.instantiateViewControllerWithIdentifier("myWorldViewController") as UIViewController)
          self.viewControllers.append(storyboard.instantiateViewControllerWithIdentifier("meViewController") as UIViewController)
          self.viewControllers.append(storyboard.instantiateViewControllerWithIdentifier("welcomeViewController") as UIViewController)
          self.tabBar.selectedItem = self.tabBar.items?.first
  
  
          //Graphical Settings
          let itemWidth = self.tabBar.frame.width / 3 as CGFloat
          let image = self.imageWithColor(UIColor.grayColor(), size: CGSizeMake(itemWidth, 49))
  
          UITabBar.appearance().barTintColor = UIColor.whiteColor()
          UITabBarItem.appearance().setTitleTextAttributes([NSFontAttributeName:UIFont(name: "Helvetica Neue", size: 20)!], forState: UIControlState.Normal)
          UITabBarItem.appearance().titlePositionAdjustment = UIOffset(horizontal: 0, vertical: -10)
          UITabBar.appearance().tintColor = UIColor.whiteColor()
          UITabBar.appearance().selectionIndicatorImage = image
  
          //Borders
          self.tabBar.layer.borderColor = UIColor.grayColor().CGColor
          self.tabBar.layer.borderWidth = 1
  
          self.tabBar(self.tabBar, didSelectItem: (self.tabBar.items?.first)!)
      }
  
      func tabBar(tabBar: UITabBar, didSelectItem item: UITabBarItem)
      {
          self.view.insertSubview(self.viewControllers[item.tag].view, belowSubview: self.tabBar)
      }
  
      override func didReceiveMemoryWarning()
      {
          super.didReceiveMemoryWarning()
      }
  
      //MARK: Utils
      func imageWithColor(color: UIColor, size: CGSize) -&gt; UIImage
      {
          let rect = CGRectMake(0, 0, size.width, size.height)
          UIGraphicsBeginImageContext(size)
          let context = UIGraphicsGetCurrentContext()
          CGContextSetFillColorWithColor(context, color.CGColor)
          CGContextFillRect(context, rect )
          let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()
          UIGraphicsEndImageContext()
  
          return image
      }
  }
  </code></pre>
  
  <p>What I need now, it to present a view controller when clicking on a button in one of the tab views. On the destination controller, I need to keep the <code>UITabBar</code> (like when using a normal <code>UITabBarController</code>). How can I do this ?</p>