I have integrated an iframe in a custom module for the checkout (carrier), lets say that I want to get the value of a hidden input onclick of a button (in the iframe) to store it somewhere (maybe cookie) to finnaly send it to a third party api (with details of the order that I already have) , how can I do that ? prestashop 1.6 -custom module
I have seen a lot of "such" kind of modules. Customer select post terminal. Enter custom values and etc on carrier step (custom carrier module).
90% they have added a custom JS code to TPL file (or create A JS file and hook to header). After customer select, enter a value just send (AJAX post) to your controller or simple php file where you can save it to database. Use id_cart to assign to this cart.
On action hook - order validation assign id_order to your database (id_cart, id_order, customer_custom_value). Thats it! Now you can use it in BO, mails and etc.