         super.viewDidLayoutSubviews()
         
         if case nil = focusView.superview, collectionView.numberOfItems(inSection: 0) > 0, let cell = collectionView.cellForItem(at: IndexPath(item: 0, section: 0)) {
+            focusView.translatesAutoresizingMaskIntoConstraints = true
+            focusView.autoresizingMask = [.flexibleWidth, .flexibleHeight, .flexibleTopMargin, .flexibleLeftMargin]
             focusView.frame = cell.frame
             collectionView.addSubview(focusView)
         }

    func menuViewController(viewController: PagingMenuViewController,  focusViewDidEndTransition focusView: PagingMenuFocusView)
}

public protocol PagingMenuViewControllerDelegate: class {
    func menuViewController(viewController: PagingMenuViewController, didSelect page: Int)
}

    public weak var delegate: PagingMenuViewControllerDelegate?
    public weak var dataSource: PagingMenuViewControllerDataSource?
    
    public var focusView = PagingMenuFocusView(frame: .zero)
    
    public var focusPointerOffset: CGPoint {
        return focusView.center
    }
