Access Container View Controller from Parent iOS

Question

in iOS6 I noticed the new Container View but am not quite sure how to access it\'s controller from the containing view.

Scenario:

Answer 1

There is another way using Swift's switch statement on the type of the view controller :

override func prepare(for segue: UIStoryboardSegue, sender: Any?)
{
  switch segue.destination
  {
    case let aViewController as AViewController:
      self.aViewController = aViewController
    case let bViewController as BViewController:
      self.bViewController = bViewController
    default:
      return
  }
}