     private var prevScrollingIndex = -1
     private var prevPageIndex = -1
     
-    private var changePageWaitForCallback = false
-    private var changePageCallback: ((Void) -> (Void))?
+    private var isWaitingForPageChangedCallback = false
+    private var pageChangedCallback: (Void -> Void)?
     
     private var tabSectionHeight: CGFloat = 0
     private var contentSectionHeight: CGFloat = 0

        }
    }
    
    // MARK: public methods
//    func scroll(offsetX: CGFloat) {
//    }
    

    
    // scrolling animation stop programmatically
    public func scrollViewDidEndScrollingAnimation(scrollView: UIScrollView) {
        if (isWaitingForPageChangedCallback) {
            isWaitingForPageChangedCallback = false
            pageChangedCallback?()
        }
    }
    
