     
     public func scrollViewDidScroll(scrollView: UIScrollView) {
         
-        var offset = scroller.contentOffset.x
+        let offset = scroller.contentOffset.x
         
         for var index = 0; index < introViews.count; index++ {
             if introViews[index].isInBound(offset){

        scroller.delegate = self
        dragger = UIView(frame: view.frame)
        dragger.backgroundColor = UIColor.clearColor()
        var gestureReco = UIPanGestureRecognizer(target: self, action: "dragged:")
        dragger.addGestureRecognizer(gestureReco)
        
        

        
        for var index = 0; index < views.count; index++ {
            
            let introView = NSBundle.mainBundle().loadNibNamed(views[index], owner: self, options: nil)[0] as! KDIntroView
            introView.center.x = view.center.x + view.frame.width * CGFloat(index)
            scroller.addSubview(introView)
            introViews.append(introView)
            
