how to hide mini controller container swift

[coucoseth]

I added mini controllers in my app following the google cast docs

func applicationDidFinishLaunching(_ application: UIApplication) {
  ...

  // Wrap main view in the GCKUICastContainerViewController and display the mini controller.
  let appStoryboard = UIStoryboard(name: "Main", bundle: nil)
  let navigationController = appStoryboard.instantiateViewController(withIdentifier: "MainNavigation")
  let castContainerVC =
          GCKCastContext.sharedInstance().createCastContainerController(for: navigationController)
  castContainerVC.miniMediaControlsItemEnabled = true
  window = UIWindow(frame: UIScreen.main.bounds)
  window!.rootViewController = castContainerVC
  window!.makeKeyAndVisible()

  ...
}

The mini controls successfully appear at the bottom in my app however my issue is that when im not casting,the space/container that the minicontrols are supposed to appear in is left blank(white space), how can i not show this space/container at all when not casting and display the controls only when casting