   
   override func viewDidLoad() {
     super.viewDidLoad()
-    createChildViewControllers()
+    makeChildViewControllers()
     tabBar.selectedItem = tabBar.items?.first
   }
   


private extension ContainerTransitionViewController {
  
  func createChildViewControllers() {
    var viewController = AnimatableViewController()
    viewController.view.backgroundColor = .blue
    viewController.transitionAnimationType = TransitionAnimationType(string: "Explode")

    viewControllers.append(viewController)
    
    cycleFromViewController(containerView, fromViewController: nil, toViewController: viewControllers[0])
  }
  
  func cycleFromViewController(_ containerView: UIView, fromViewController: AnimatableViewController?, toViewController: AnimatableViewController) {
