jQuery Grid Plugin - jqGrid

in demo"Array Data",if add some data to mydata and mydata.length > 20

and set:

<table id="list4″></table>
<div id="pager2″></div>

rowNum:10,
    rowList:[10,20,30],
    pager: '#pager2',

the demo is not work right

code:

$(document).ready(function(){

jQuery("#list4″).jqGrid({
    datatype: "local",
    height: 200,
    colNames:['Inv No','Date', 'Client', 'Amount','Tax','Total','Notes'],
    colModel:[ {name:'id',index:'id', width:60, sorttype:"int"},
            {name:'invdate',index:'invdate', width:90, sorttype:"date"},
            {name:'name',index:'name', width:100},
            {name:'amount',index:'amount', width:80, align:"right",sorttype:"float"},
            {name:'tax',index:'tax', width:80, align:"right",sorttype:"float"},
            {name:'total',index:'total', width:80,align:"right",sorttype:"float"},
            {name:'note',index:'note', width:150,editable: true,edittype:"checkbox",editoptions: {value:"Yes:No"}, sortable:false} ],
    multiselect: true,
rowNum:10,
    rowList:[10,20,30],
    pager: '#pager2',
    sortname: 'id',
    viewrecords: true,
    sortorder: "desc",
    caption: "Manipulating Array Data" });
    
    jQuery("#list4″).jqGrid('navGrid','#pager2',{edit:false,add:false,del:false});

    
    var mydata = [ {id:"1",invdate:"2007-10-01",name:"test",note:"note",amount:"200.00",tax:"10.00",total:"210.00"},
    {id:"2",invdate:"2007-10-02",name:"test2",note:"note2",amount:"300.00",tax:"20.00",total:"320.00"},
    {id:"3",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"},
    {id:"4",invdate:"2007-10-04",name:"test",note:"note",amount:"200.00",tax:"10.00",total:"210.00"},
    {id:"5",invdate:"2007-10-05",name:"test2",note:"note2",amount:"300.00",tax:"20.00",total:"320.00"},
    {id:"6",invdate:"2007-09-06",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"},
    {id:"7",invdate:"2007-10-04",name:"test",note:"note",amount:"200.00",tax:"10.00",total:"210.00"},
    {id:"8",invdate:"2007-10-03",name:"test2",note:"note2",amount:"300.00",tax:"20.00",total:"320.00"},
    {id:"9",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"},
    {id:"10",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"11",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"12",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"13",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"14",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"15",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"16",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"17",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"18",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"19",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"} ,
    {id:"20",invdate:"2007-09-01",name:"test3",note:"note3",amount:"400.00",tax:"30.00",total:"430.00"}  ];
        //for(var i=0;i<=10;i++)
     for(var i=0;i<=mydata.length;i++)
        jQuery("#list4″).jqGrid('addRowData',i+1,mydata[i]);
        
    //    jQuery("#list4″).jqGrid('editRow',"1″);
        
 
});