             cachedViewControllers[page] = vc
         }
     }
-    
-    var isTracking = false
 }
 
 extension PagingContentViewController: UIScrollViewDelegate {
     public func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
-        isTracking = true
+        isExplicityScrolling = true
         delegate?.contentViewController(viewController: self, willBeginScrollFrom: leftSidePageIndex)
     }
     

    }
    
    public func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
        isTracking = false
        loadPagesIfNeeded()
    }
    
    public func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
        if !decelerate {
            isTracking = false
            loadPagesIfNeeded()
        }
    }
    
    public func scrollViewDidEndScrollingAnimation(_ scrollView: UIScrollView) {
        isProgramaticallyScrolling = false
    }
    
    fileprivate func loadPagesIfNeeded(page: Int? = nil) {

    
    fileprivate var lastContentOffset = CGPoint.zero
    fileprivate var leftSidePageIndex = 0
    fileprivate var isExplicityScrolling = false
    
    fileprivate let scrollView: UIScrollView = {
        let scrollView = UIScrollView()
