PHP JQGrid Zend Framework

Question

I am trying to JQGrid in Zend Framework , but not working. I am getting the Json formated string as output

Controller:

<?php
// require_once 'Zend/Controller/Action.php';
class TestController extends BaseController 
{
    public function indexAction() 
    {
        // TODO Auto-generated TestController::indexAction() default action
        // $this->view->pageTitle = 'Competitors';
        $sidx = $this->getRequest()->getParam('sidx');
        $sord = $this->getRequest()->getParam('sord');
        $page = $this->getRequest()->getParam('page');
        $limit = 10 ; //R $this->getRequest()->getParam('rows');
        $s = new Test();
        $count =  $s->getNbrRace();
        //$this->view->pageTitle = 'Competitors'.$count;
        if( $count > 0 ) 
        {   $total_pages = ceil($count/$limit);        } 
        else 
        {   $total_pages = 0;        }
        if ($page > $total_pages) 
            $page=$total_pages;
        $start = ($limit * $page)-$limit;
        if ($start<0) 
            $start=0;
        $row = $s->getListRace($sidx,$sord,$start,$limit);
        $response['page'] = 1;// $page;
        $response['total'] = $total_pages;
        $response['records'] = $count;
        $i=0;
        foreach ($row as $r) 
        {
            $response['rows'][$i]['id']=$r->r_id; //id
            $response['rows'][$i]['cell']=array($r->r_id,$r->r_name,$r->r_date);
            $i++;
        }
        //$this->_helper->json($response);
        echo json_encode($response);
        //echo json_encode($responce);
    }
}
?>

index.phtml:

<table id="list2"></table>
<div id="pager2"></div>
<script type="text/javascript">
jQuery("#list2").jqGrid({
    url:'<?php echo $this->baseUrl()?>/test/test.php',
    datatype: "json",
    colNames:['r_id','r_name','r_date'],
    colModel:[
    {name:'r_id',index:'r_id', width:55},
    {name:'r_name',index:'r_name', width:90},
    {name:'r_date',index:'r_date', width:100}
    ],
    rowNum:10,
    rowList:[10,20,30],
    pager: '#pager2',
    sortname: 'id',
    viewrecords: true,
    sortorder: "desc",
    caption:"JSON Example"
});
jQuery("#list2").jqGrid('navGrid','#pager2',{edit:false,add:false,del:false});
</script>

Test.php:

<?php
Class Test extends BaseDbTable
{
    protected $_name             = 'races';
    protected $_primary          = 'r_id';

    public function getListRace($idx,$ord,$start,$limit) 
    {
        $select = $this->select()
        ->setIntegrityCheck(false)
        ->from(array('c' => $this->getName()) , array('r_id','r_name','r_date'));
        $fetch = $this->fetchAll($select);
        return $fetch;          
    }
    public function getNbrRace() 
    {       
        $select = $this->select()
        ->setIntegrityCheck(false)
        ->from(array('c' => $this->getName()) , array('r_id'));
        $fetch = $this->fetchAll($select);
        return $fetch->count();
    }

}
?>