 
 public extension UIScrollView {
     public func addTopRefreshContainerViewWithHeight(height: CGFloat, actionCallback: RefreshActionCallback?) -> Void {
-        removeTopPullToRefresh()
-        
         let topRefreshContainerView: TopRefreshContainerView = TopRefreshContainerView(height: height, scrollView: self)
         addSubview(topRefreshContainerView)
         self.topRefreshContainerView = topRefreshContainerView

    }
    
    public func removeTopPullToRefresh() -> Void {
        topRefreshContainerView?.removeFromSuperview()
        topRefreshContainerView = nil
    }

// MARK: - BottomRefreshContainerView

public extension UIScrollView {
    public func addBottomRefreshContainerViewWithHeight(height: CGFloat, actionCallback: RefreshActionCallback?) -> Void {        
        let bottomRefreshContainerView: BottomRefreshContainerView = BottomRefreshContainerView(height: height, scrollView: self)
        addSubview(bottomRefreshContainerView)
        self.bottomRefreshContainerView = bottomRefreshContainerView
