init model from controller joomla 3.1 - php

Question

I try to call a model from one of my Joomla controller but that doesn't seem to work.
class TieraerzteControllerDatatable extends JControllerLegacy
{
/**
* display task
*
* #return void
*/
function display($cachable = false)
{
// set default view if not set
$input = JFactory::getApplication()->input;
$model = $this->getModel('datatable');
$model->getTableData('grumpi_tieraerzte', 'id', array('id','name','strasse','telefon','fax'));
die();
}
}
In my model I placed a var_dump but it is not accessed. How can I debug my model call in controller?
I try to access the models return with the following url /administrator/index.php?option=com_tieraerzte&task=datatable.display&{arguments for the model}
trying to debug my codes piece by piece seems like the model is accessed and this code is causing the problem
// Paging
$sLimit = "";
if (isset(JRequest::getVar('iDisplayStart')) && JRequest::getVar('iDisplayLength') != '-1')
{
$sLimit = "LIMIT " . intval(JRequest::getVar('iDisplayStart')) . ", " . intval(JRequest::getVar('iDisplayLength'));
}
The whole method:
public function getTableData($table, $index_column, $columns)
{
$db = JFactory::getDbo();
$query = $db->getQuery(true);
// Paging
$sLimit = "";
if (isset(JRequest::getVar('iDisplayStart')) && JRequest::getVar('iDisplayLength') != '-1')
{
$sLimit = "LIMIT " . intval(JRequest::getVar('iDisplayStart')) . ", " . intval(JRequest::getVar('iDisplayLength'));
}
// Ordering
$sOrder = "";
if (isset(JRequest::getVar('iSortCol_0')))
{
$sOrder = "ORDER BY ";
for ($i = 0; $i < intval(JRequest::getVar('iSortingCols')); $i++)
{
if (JRequest::getVar('bSortable_' . intval(JRequest::getVar('iSortCol_' . $i))) == "true")
{
$sortDir = (strcasecmp(JRequest::getVar('sSortDir_' . $i), 'ASC') == 0) ? 'ASC' : 'DESC';
$sOrder .= "`" . $columns[intval(JRequest::getVar('iSortCol_' . $i))] . "` " . $sortDir . ", ";
}
}
$sOrder = substr_replace($sOrder, "", -1);
if ($sOrder == "ORDER BY") {
$sOrder = "";
}
}
/*
* Filtering
* NOTE this does not match the built-in DataTables filtering which does it
* word by word on any field. It's possible to do here, but concerned about efficiency
* on very large tables, and MySQL's regex functionality is very limited
*/
$sWhere = "";
if (isset(JRequest::getVar('sSearch')) && JRequest::getVar('sSearch') != "")
{
$like = '%' . JRequest::getVar('sSearch') . '%';
$sWhere = "WHERE (";
for ($i = 0; $i < count($columns); $i++)
{
if (isset(JRequest::getVar('bSearchable_' . $i)) && JRequest::getVar('bSearchable_' . $i) == "true")
{
$sWhere .= "`" . $columns[$i] . "` LIKE '" . $like . "' OR ";
}
}
$sWhere = substr_replace($sWhere, "", -3);
$sWhere .= ')';
}
// Individual column filtering
for ($i = 0; $i < count($columns); $i++)
{
if (isset(JRequest::getVar('bSearchable_' . $i)) && JRequest::getVar('bSearchable_' . $i) == "true" && JRequest::getVar('sSearch_' . $i) != '')
{
if ($sWhere == "")
{
$sWhere = "WHERE ";
} else {
$sWhere .= " AND ";
}
$sWhere .= "`" . $columns[$i] . "` LIKE ? " . $i . " ";
}
}
// SQL queries get data to display
$sQuery = "SELECT SQL_CALC_FOUND_ROWS `" . str_replace(" , ", " ", implode("`, `", $columns)) . "` FROM `" . $table . "` " . $sWhere . " " . $sOrder . " " . $sLimit;
$statement = $this->_db->prepare($sQuery);
// Bind parameters
if (isset(JRequest::getVar('sSearch')) && JRequest::getVar('sSearch') != "")
{
$statement->bind_param('s', $like);
}
for ($i = 0; $i < count($columns); $i++)
{
if (isset(JRequest::getVar('bSearchable_' . $i)) && JRequest::getVar('bSearchable_' . $i) == "true" && JRequest::getVar('sSearch_' . $i) != '')
{
$statement->bind_param('s' . $i, '%' . $_GET['sSearch_' . $i] . '%');
}
}
$db->setQuery($sQuery);
$res = $db->loadObjectList();
$rResult = array();
foreach ($res as $row)
{
$rResult[] = $row;
}
$iFilteredTotal = current($db->setQuery('SELECT FOUND_ROWS()')->loadResultArray());
// Get total number of rows in table
$sQuery = "SELECT COUNT(`" . $index_column . "`) FROM `" . $table . "`";
$iTotal = current($db->setQuery($sQuery));
// Output
$output = array(
"sEcho" => intval($_GET['sEcho']),
"iTotalRecords" => $iTotal,
"iTotalDisplayRecords" => $iFilteredTotal,
"aaData" => array()
);
// Return array of values
foreach ($rResult as $aRow)
{
$row = array();
array_push($row, '<input type="checkbox" id="someCheckbox" name="someCheckbox" />');
for ($i = 0; $i < count($columns); $i++)
{
//var_dump($aRow->$columns[$i]);
if ($columns[$i] != '')
{
$row[] = $aRow->$columns[$i];
}
}
array_push($row, '
<div class="btn-group" id="status">
<input type="button" class="btn b1" value="On">
<input type="button" class="btn b0 btn-danger" value="Off">
</div>
');
array_push($row, '
<div class="clearfix">
<div class="label label-important" style="padding:6px 9px; margin-right:5px"><span class="icon-trash"></span></div>
<div class="label label-success" style="padding:6px 9px"><span class="icon-cog"></span></div>
</div>
');
$output['aaData'][] = $row;
}
echo json_encode($output);
}

Answer 1

Make sure $model inside the controller is not null. If it's not null, than the problem is somewhere in the model's method called.
if $model is null, somehow the model you are calling is not loaded. Temporary try just to include the file with require_once JPATH_COMPONENT . '/models/datatable.php'