Prestashop: How to filter in HelperList - prestashop

Question

Hello I try to filter a List in the Backoffice. It shows the filter, it also saves it after clicking on search, but nothing is happening. Same with pagination.
$schueler = $this->getAllSchuelerbyDiplom($id_diplom);
$diplom_name = $this->getDiplomNamebyID($id_diplom);
$fields_list = array(
'id_schueler' => array(
'title' => 'ID',
'align' => 'center',
'class' => 'fixed-width-xs',
'search' => true),
'customer_name' => array(
'title' => $this->l('ID Customer')),
'id_gruppe' => array(
'title' => $this->l('ID Gruppe')),
'name' => array(
'title' => $this->l('Name'),
'filter_key' => 'name'.$diplom_name),
'vorname' => array(
'title' => $this->l('Vorname')),
'punkte' => array(
'title' => $this->l('Punkte')),
'bestanden' => array(
'title' => $this->l('Bestanden'),
'active' => 'toggle',
'class' => 'fixed-width-xs',
'type' => 'bool'),
'date_added' => array(
'title' => $this->l('Datum'),
'class' => 'fixed-width-xs',
'type' => 'date'),
);
$helper = new HelperList();
$helper->table = 'no-idea-what-this-is-for';
$helper->title = $diplom_name;
$helper->shopLinkType = '';
$helper->actions = array('view', 'edit', 'delete');
$helper->listTotal = count($schueler);
$helper->identifier = 'id_schueler';
$helper->token = Tools::getAdminTokenLite('AdminModules');
$helper->currentIndex = $this->context->link->getAdminLink('AdminModules', false) . '&configure=' . $this->name .'&diplom_name=' . $diplom_name;
return $helper->generateList($schueler, $fields_list);
What is wrong with my code? What is $helper->table for? I tried different things there, but nothing helps...
EDIT
public function getAllSchuelerbyDiplom($id_diplom) {
$query = new DbQuery();
$query->select('s.*, CONCAT(c.firstname,\' \',c.lastname) AS customer_name');
$query->from($this->table_name.'_schueler', 's');
$query->leftJoin('customer', 'c', 's.id_customer = c.id_customer');
$query->where('s.id_diplom = ' . (int)$id_diplom);
return Db::getInstance()->ExecuteS($query);
}

Answer 1

The problem is that HelperList object itself will only display filters being used but won't filter the actual data list for you.
In your $this->getAllSchuelerbyDiplom($id_diplom); method I assume you execute SQL query to retrieve all rows, however you need modify it to account for any filters, paginations (page number and rows per page) or ordering. You have to check GET/POST values or values set in cookie to detect them.
$helper->table sets the table name and list actions are prepended with that name so they are distinct from any other lists you might have on the page.
Edit:
Example of setting pagination and page
public function getPage()
{
// $tableName must be equal to what you set in $helper->table
// Check if page number was selected and return it
if (Tools::getIsset('submitFilter'.$tableName)) {
return (int)Tools::getValue('submitFilter'.$tableName);
}
else {
// Check if last selected page is stored in cookie and return it
if (isset($this->context->cookie->{'submitFilter'.$tableName})) {
return (int)$this->context->cookie->{'submitFilter'.$tableName};
}
else {
// Page was not set so we return 1
return 1;
}
}
}
public function getRowsPerPage()
{
// $tableName must be equal to what you set in $helper->table
// Check if number of rows was selected and return it
if (Tools::getIsset($tableName. '_pagination')) {
return (int)Tools::getValue($tableName. '_pagination');
}
else {
// Check if number of rows is stored in cookie and return it
if (isset($this->context->cookie->{$tableName. '_pagination'})) {
return (int)$this->context->cookie->{$tableName. '_pagination'};
}
else {
// Return 20 rows per page as default
return 20;
}
}
}
public function getAllSchuelerbyDiplom($id_diplom) {
$query = new DbQuery();
$query->select('s.*, CONCAT(c.firstname,\' \',c.lastname) AS customer_name');
$query->from($this->table_name.'_schueler', 's');
$query->leftJoin('customer', 'c', 's.id_customer = c.id_customer');
$query->where('s.id_diplom = ' . (int)$id_diplom);
// Limit the result based on page number and rows per page
$query->limit($this->getRowsPerPage(), ($this->getPage() - 1) * $this->getRowsPerPage());
return Db::getInstance()->ExecuteS($query);
}
You can place a p(Tools::getAllValues()); d($this->context->cookie->getAll(); after you generate a list then set a filter in your list and it will show you all the variables you need to create filters and ordering.