             scrollView.addSubview(vc.view)
             vc.didMove(toParent: self)
             cachedViewControllers[page] = vc
-        }
-    }
-    
-    fileprivate func layoutScrollView(with page: Int) {
-        guard (0..<cachedViewControllers.count) ~= page else { return }
-        
-        if let vc = cachedViewControllers[page] {
-            vc.view.frame = scrollView.bounds
-            vc.view.frame.origin.x = scrollView.bounds.width * CGFloat(page)
         }
     }
     

        loadScrollView(with: page - 1)
        loadScrollView(with: page)
        loadScrollView(with: page + 1)
    }
    
    fileprivate func relocate(with page: Int) {
        layoutScrollView(with: page - 1)
        layoutScrollView(with: page)
        layoutScrollView(with: page + 1)
    }
    
    fileprivate func loadScrollView(with page: Int) {

    }

    override public func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
        coordinator.animate(alongsideTransition: { [weak self] (context) in
            guard let _self = self else { return }
            _self.scroll(to: _self.leftSidePageIndex, animated: false)
