public function getFilters($source)
{
$filters = array();
// Apply same filters on each column
foreach ($this->joinColumns as $columnName) {
$tempFilters = parent::getFilters($source);
foreach ($tempFilters as $filter) {
$filter->setColumnName($columnName);
}
$filters = array_merge($filters, $tempFilters);
}
return $filters;
}
