Creating Subtables in Piwik

I am new to piwik.Please help me in my issue.

Issue: I have to create 4 levesl of subtables.Currently I can able to create upto 2nd level,I mean table 开发者_开发问答with one subtable per row. Basically If I click on a table row I shoud get the subtable.If I click on subtable row again it should show inner subtable. I need to create Table->subtable->subtable->subtable.

My code :

function getpageViewsLevel1($idSite, $date, $period)
        {

         $query = "select * from....";

                $result = Piwik_FetchAll($query, array($idSite, $dateStart, $dateEnd));

                // convert this array to a DataTable object
                $dataTable = new Piwik_DataTable();

                //Add subtable to each result
                foreach ($result as $arr){
                        $piwik_row = new Piwik_DataTable_Row;
                        $piwik_row->setColumns($arr);
                        $subDataTable = new Piwik_DataTable();
                        $piwik_row->addSubTable($subDataTable);
                        $dataTable->addRow($piwik_row);
                }
                return $dataTable;
        }

function getpageViewsLevel2($idSite, $date, $period, $idSubtable)
        {

                // Find selected parent row and retrieve data

                $dataTable_old = $this->getpageViewsLevel1($idSite, $date, $period);
                $row_old = new Piwik_DataTable_Row;
                $row_old=$dataTable_old->getRowFromIdSubDataTable($idSubtable+1);

                $tmp=$row_old->getColumns();
                //Using $actionName in DB Query
                $actionName=$tmp['pageTitle'].'%';

                //db query
                $query = "select * ....";

                $result = Piwik_FetchAll($query, array($idSite, $dateStart, $dateEnd, $actionName));

                // convert this array to a DataTable object
                //$dataTable = new Piwik_DataTable();
                foreach ($result as $arr){
                        $piwik_row = new Piwik_DataTable_Row;
                        $piwik_row->setColumns($arr);
                    $subDataTable = new Piwik_DataTable();
                        $piwik_row->addSubTable($subDataTable);
                        $dataTable->addRow($piwik_row);
                }
                return $dataTable;
        }

Till here works fine.For the 3rd level,I am not able to apply the same logic as I dont have the 2ng level table ID.

function getpageViewsLevel3($idSite, $date, $period, $idSubtable)
        {

                // Find selected parent row and retrieve data

                $dataTable_old = $this->getpageViewsLevel2($idSite, $date, $period, ___???????????????);

Please help me how can I proceed with this issue.Please let me know is there any other solution to do this. Though if I pass some number like '1' for testing,

$dataTable_old = $this->getpageViewsLevel2($idSite, $date, $period, 1);----->this is not working.

I need to use parent row info in my DB query.

Thanks in advance for your help.