Hello everyone, It's been a while since I posted my issue. Actually I found what the problem was, so here is the answer.
When you want to display your own fields (that you added in the Product Class), it depends on the page you are :
Assuming the customer wants the products sorted by suppliers, he's on the page ..yoursite.com/supplier.php?id_supplier=XX
So you should modify the Supplier class, the function remain the same for all the class : getProducts(...)
You have something like this :
///////////////////////////////////////////////////////////////////////////////////////////////
$sql = '
SELECT p.*, pl.`yourownfield`, pl.`yourownfield2`,pl.`yourownfield3`, pl.`description_short`, pl.`link_rewrite`, pl.`meta_description`, pl.`meta_keywords`, pl.`meta_title`, pl.`name`, i.`id_image`, il.`legend`, s.`name` AS supplier_name, tl.`name` AS tax_name, t.`rate`, DATEDIFF(p.`date_add`, DATE_SUB(NOW(), INTERVAL '.(Validate::isUnsignedInt(Configuration::get('PS_NB_DAYS_NEW_PRODUCT')) ? Configuration::get('PS_NB_DAYS_NEW_PRODUCT') : 20).' DAY)) > 0 AS new,
(p.`price` * ((100 + (t.`rate`))/100)) AS orderprice, m.`name` AS manufacturer_name
FROM `'._DB_PREFIX_.'product` p
LEFT JOIN `'._DB_PREFIX_.'product_lang` pl ON (p.`id_product` = pl.`id_product` AND pl.`id_lang` = '.(int)($id_lang).')
LEFT JOIN `'._DB_PREFIX_.'image` i ON (i.`id_product` = p.`id_product` AND i.`cover` = 1)
LEFT JOIN `'._DB_PREFIX_.'image_lang` il ON (i.`id_image` = il.`id_image` AND il.`id_lang` = '.(int)($id_lang).')
LEFT JOIN `'._DB_PREFIX_.'tax_rule` tr ON (p.`id_tax_rules_group` = tr.`id_tax_rules_group`
AND tr.`id_country` = '.(int)Country::getDefaultCountryId().'
AND tr.`id_state` = 0)
LEFT JOIN `'._DB_PREFIX_.'tax` t ON (t.`id_tax` = tr.`id_tax`)
LEFT JOIN `'._DB_PREFIX_.'tax_lang` tl ON (t.`id_tax` = tl.`id_tax` AND tl.`id_lang` = '.(int)($id_lang).')
LEFT JOIN `'._DB_PREFIX_.'supplier` s ON s.`id_supplier` = p.`id_supplier`
LEFT JOIN `'._DB_PREFIX_.'manufacturer` m ON m.`id_manufacturer` = p.`id_manufacturer`
WHERE p.`id_supplier` = '.(int)($id_supplier).($active ? ' AND p.`active` = 1' : '').'
AND p.`id_product` IN (
SELECT cp.`id_product`
FROM `'._DB_PREFIX_.'category_group` cg
LEFT JOIN `'._DB_PREFIX_.'category_product` cp ON (cp.`id_category` = cg.`id_category`)'.
($active_category ? ' INNER JOIN `'._DB_PREFIX_.'category` ca ON cp.`id_category` = ca.`id_category` AND ca.`active` = 1' : '').'
WHERE cg.`id_group` '.$sqlGroups.'
)
ORDER BY '.(($orderBy == 'id_product') ? 'p.' : '').'`'.pSQL($orderBy).'` '.pSQL($orderWay).'
LIMIT '.(((int)($p) - 1) * (int)($n)).','.(int)($n);
///////////////////////////////////////////////////////////////////////////////////////////////
Add your fields like above.
So each time you want to display your own fields in a page, add your code into the getProducts(...) function of this page.
I hope everything is clear.
Best regards,
N44PS