easyUi表格颜色设置

$(function() {        $('.btn_state').linkbutton('disable');    $('#dg').datagrid({        url : _getPage,        rownumbers : true,        pagination : true,        fitColumns : true,        fit : true,        singleSelect : false,        pageSize : 20,        pageList : [20, 30, 50],        remoteSort:true,        multiSort:true,        queryParams : {conditions : getSearchConditions()},        columns : [[            {field: 'id', title: "id", checkbox:true, hidden: false, width: 100, sortable: true, align: 'center'},            {field :'serviceCategory',title:'Service Category',hidden:false,width:50,sortable:true,align : 'center',                //加一个方法(用来设置颜色的)                styler:rowColor            },            {field :'serviceModel',title:'Service Model',hidden:false,width:50,sortable:true,align : 'center'},            {field :'description',title:'Description',hidden:false,width:50,sortable:true,align : 'center'}            ]]          });    var pager = $('#dg').datagrid('getPager');    pager.pagination({        beforePageText: '第',//页数文本框前显示的汉字         afterPageText: '页    共 {pages} 页',         displayMsg: '当前显示 {from} - {to} 条记录   共 {total} 条记录',     });});//后台需要的条件function getSearchConditions(){    var param = [];    var filterVal = $("#selectModelSearch").val();    if(filterVal != null){        param.push({"name":"dictNameFilter","value":filterVal});    }    if(serviceCategory != null){        param.push({"name":"serviceCategory","value":serviceCategory});    }    if(id != null){        param.push({"name":"id","value":id});    }    var conditions =  $.toJSON(param);    return conditions;  }//查询表格数据，添加事件就可以，什么都不需要考虑function searchGrid() {    var queryParams = {        conditions : getSearchConditions()    };    $('#dg').datagrid('load', queryParams);}//颜色设置function rowColor(value, row, index) {    if(row.serviceCategory=='GSM'){        return 'background-color:red;color:white';    }    if(row.serviceCategory=='WCDMA'){        return 'background-color:cyan;color:white';    }    //alert(row.serviceCategory); }