下拉加载时无限空白

mui.each(document.querySelectorAll('.mui-slider-group .mui-slider-item .mui-scroll'), function(index, pullRefreshEl) {  
            mui(pullRefreshEl).pullToRefresh({  
                down: {  
                    callback: function() {  
                        var self = this;  
                        //下拉刷新  
                        self.endPullDownToRefresh();  
                    }  
                },  
                up: {  
                    callback: function() {  
                        var self = this;  
                        //上拉加载  
                        self.endPullUpToRefresh();  
                    }  
                }  
            });  
        });

<div class="mui-slider-group">
<div id="#item-find" class="mui-slider-item mui-control-content mui-active">
<div class="mui-scroll-wrapper">
<div class="mui-scroll">