下拉刷新时取消不了怎么办

$.ready(function() {
//循环初始化所有下拉刷新，上拉加载。
$.each(sel, function(index, pullRefreshEl) {
var num = this.getAttribute('index');

                    $(pullRefreshEl).pullToRefresh({  
                        down: {  
                            callback:function(){  
                                mui.ajax('en',{  
                                    data:{},  
                                    dataType:'json',  
                                    type:'get',  
                                    success:function(data){  
                                        var table = document.getElementById('table')  
                                        var text = data.rows[0].content;  
                                        var alg = document.createElement("a");  
                                        alg.innerHTML = text;  
                                        table.insertBefore(alg,table.firstChild);  
                                        alert(sel[num].innerHTML);  
                                    }  

                                })  

                            }  
                        }  
                    });  

                });  
            });