     
     // 懒加载 headView
     lazy var headView: SDCycleScrollView =  {
+        
         let headView: SDCycleScrollView = SDCycleScrollView.init(frame: CGRect(x: 0.0, y: 0.0, width: self.view.bounds.size.width, height: headViewHeight), delegate: self, placeholderImage: UIImage(named: "default_user_icon_75x75_"))
-        
-        
-        
-        
         
         headView.currentPageDotColor = UIColor.yellowColor()
         

        currentChildVc.tableView.contentOffset.y = currentOffsetY - defaultOffSetY
        
        
//                let offset: CGFloat = scrollView.contentOffset.y
        
                var alpha: CGFloat = currentOffsetY * 1 / 98.0
        
        
                if alpha <= 0 {
        
                }
        
                if alpha >= 1 {
                    alpha = 0.99
                    navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(named: "home_sign_top_icon_19x19_"), highlightImage: nil, target: self, action: #selector(signClick))
                } else {
                    navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(named: "home_sign_icon_33x33_"), highlightImage: UIImage(named: "home_sign_highlight_icon_33x33_"), target: self, action: #selector(signClick))
                }
        
                navigationController?.navigationBar.setBackgroundImage(UIImage(color: UIColor(white: 1.0, alpha: alpha)), forBarMetrics: .Default)
        
        
        

        
        if offSetY < -(defaultOffSetY - headViewHeight + naviBarHeight) {
            

            navigationBarAlpha = currentOffsetY * 1 / 98.0
            
            
            if navigationBarAlpha <= 0 {
                
            }
            
            if navigationBarAlpha >= 1 {

                navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(named: "home_sign_top_icon_19x19_"), highlightImage: nil, target: self, action: #selector(signClick))
            } else {
                navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(named: "home_sign_icon_33x33_"), highlightImage: UIImage(named: "home_sign_highlight_icon_33x33_"), target: self, action: #selector(signClick))
            }

            navigationController?.navigationBar.zz_setBackgroundColor(UIColor.whiteColor().colorWithAlphaComponent(navigationBarAlpha))
            navigationController?.navigationBar.zz_setElementAlpha(navigationBarAlpha)
            
        }
        
        
        if offSetY > -(defaultOffSetY - headViewHeight + naviBarHeight) {
            if topView.frame.origin.y == naviBarHeight {
                navigationBarAlpha = 1.0
                navigationController?.navigationBar.zz_setBackgroundColor(UIColor.whiteColor().colorWithAlphaComponent(navigationBarAlpha))
                return
            }
            // 使滑块停在navigationBar下面
            self.scrollView.frame.origin.y = naviBarHeight - headViewHeight
            topView.frame.origin.y = naviBarHeight

            navigationBarAlpha = 1.0
        navigationController?.navigationBar.zz_setBackgroundColor(UIColor.whiteColor().colorWithAlphaComponent(navigationBarAlpha))
            
            return
        } else if offSetY < -defaultOffSetY {
