jQuery Grid Plugin - jqGrid

var leaf = len-1 === n.idx; 
                if( leaf ) {
                    var gg = grp.groups[i+1], kk, ik, offset = 0, sgr = n.startRow,
                  //Line that gives the exception:
                    end = gg !== undefined ?  grp.groups[i+1].startRow : grdata.length; 
                    if(grp._locgr) {
                        offset = (page-1)*rn;
                        if(offset > n.startRow) {
                            sgr = offset;
                        }
                    }

function showProductList()
{    
    if(reloadProducts)
    {
    //HTML Web Service CalL
    var xmlhttp=false;
    var getCustomersUrl =  serviceTrigger; //Web Service URL from which I retrieve the XML
    xmlhttp = new XMLHttpRequest();
    
    xmlhttp.open("POST", getCustomersUrl, true); //B1if only allows POST requests!
    xmlhttp.setRequestHeader("Content-Type", "text/xml; charset=utf-8");
    
    var data = '<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:tem="http://tempuri.org/"><soapenv:Header/><soapenv:Body><tem:GetProductList><tem:Group>'+selectedGroup+'</tem:Group></tem:GetProductList></soapenv:Body></soapenv:Envelope>'
    console.log(data);
    xmlhttp.onreadystatechange=function () {
        
        if(xmlhttp.readyState==4)
        {
            productListData = xmlhttp.responseText;
            buildProductGrid(); // ---> Method that builds my grid
            reloadProducts = false;
        }
        console.log("Loading of Service not done yet");
        
    }; //END of READY STATE FUNCTION
    
    //Sending the Request
    xmlhttp.send(data);
    }else 
    {
        buildProductGrid(); // ---> Method that builds my grid

function buildProductGrid()
{
    jQuery(document).ready(function () {
    
            //Last Selected Row - used for Selection Handling
            lastsel = null;
            var monthHeaders = getMonthHeader();
            //Definition of Grid
        $("#list").jqGrid({
            datatype: 'xmlstring', //Datatype of information represented, will be XML due to HTTP call I guess?
            datastr: productListData, // --> this is what is created in the previous function
        colNames: ['Hersteller','Artikel Nr', 'PZN', 'Beschreibung', 'Menge', 'NR', 'P', 'K', 'A','VJ','VVJ',monthHeaders[0],monthHeaders[1],monthHeaders[2],monthHeaders[3],monthHeaders[4],monthHeaders[5],monthHeaders[6],monthHeaders[7],monthHeaders[8],monthHeaders[9],monthHeaders[10],monthHeaders[11]],//'Check','Notes'], //Header Layer Definition
        colModel:[
            //GroupColumn
            {name:'xxx', index:'xxx',width:1,editable:false,search: false},
            {name:'itmc',index:'itmc', width:80, align:"left",search:true, key:true},
            {name:'pzn',index:'pzn', width:65, align:"left",search:true},
            {name:'itemnm',index:'itemnm', width:200, align:"left",sorttype:"text",search:true},
            //EditableParts
            {name:'amount', index:'amount', width:40,align:"center",sorttype:"number", editoptions:{size:4, maxlenght:4, height:40},editrules:{number:true},editable:true,search:false},
            {name:'nr',index:'nr',width:40,align:"center",sorttype:"number",editoptions:{size:4, maxlenght:4},editrules:{number:true},editable:true,search:false},
            {name:'p', index:'p',width:30,align:"center",sortable:false, edittype:'checkbox',editoptions:{value:"Ja:Nein"},editable:true,search:false},
            {name:'k', index:'k',width:30,align:"center",sortable:false, edittype:'checkbox',editoptions:{value:"Ja:Nein"},editable:true,search:false},
            {name:'a', index:'a',width:30,align:"center",sortable:false, edittype:'checkbox',editoptions:{value:"Ja:Nein"},editable:true,search:false},
            //END EditableParts
            {name:'year12',index:'year12', width:40, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'year13',index:'year13', width:40, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon1',index:'mon1', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon2',index:'mon2', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon3',index:'mon3', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon4',index:'mon4', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon5',index:'mon5', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon6',index:'mon6', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon7',index:'mon7', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon8',index:'mon8', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon9',index:'mon9', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon10',index:'mon10', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon11',index:'mon11', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            {name:'mon12',index:'mon12', width:35, formatter:'text', align:"center",sorttype:"number",search:false},
            //{name:'check',index:'check', width:40,editRow:true, editable:true, align:"center", edittype:'checkbox',editoptions:{value:"Yes:No"}},
            //{name:'note',index:'note', width:100,editRow:true, sortable:false, editable:true, editoptions:{maxLenght:'40'}}
        ],
        //pager: '#pager', //Pager Setup - to go back and forth between entrys #Might solve our display problem!
        rowNum: 9999,         //Number of Rows to display, the pager switches back and forth
        //rowList: [10, 15, 20], //Defines a drop down  Menu to change rowNum (probably not usable in Ipad dev)
        sortname: 'xxx',    //Initial sorting column pretty straight forward
        sortorder: 'asc',    //Sortorder self explanatory
        viewrecords: true, //Number of total records available
        gridview: true,    
        autoencode: true,
        caption: selectedCustomerName,
        height: 500,
        ignoreCase: true,
        grouping : true,
        groupingView: {
            groupField: ['xxx'],
            groupColumnShow: [false],
            groupText: ['{0} - {1} Item(s)'],
            groupCollapse:false,
            //groupDataSorted: true,
            //groupOrder: ['asc']
        },
        onSelectRow: function(id){
            if(id!=lastsel){
                jQuery('#list').jqGrid('saveRow',lastsel);
                //Adding Value for Submission Counter
                makeAmountOutput();
                
                //Set Null, select new Row
                lastsel = null;
                //jQuery('#list').jqGrid('editRow',id, { keys:true, oneditfunc : function( rowid) {$("#"+rowid+"_NR").focus();}};
                jQuery('#list').jqGrid('editRow',id, {   keys: true,   oneditfunc : function( rowid) {     $("#"+rowid+"_NR").focus();   } });
                lastsel=id;
                
            }else
            {
                makeAmountOutput();
                jQuery('#list').jqGrid('editRow',id, {   keys: true,   oneditfunc : function( rowid) {     $("#"+rowid+"_NR").focus();   } });
            }
        },
        scrollOffset: 0,
        editurl: "default.html",
        hidegrid:false,
        
    }); //JqGird Definition END

    //Definition of Filter Search
    $("#list").jqGrid('filterToolbar',{
        searchOnEnter: false
        
    });
    
    });    
};