I working on lesson mod. I want to make this mod is compatible with Ajax. I solved the a lot of problem but I stucked in question form submit via Ajax. I am able to send the form data to php file(form serialization and get method), but mform->get_data() function is returning null when the multichoice.php check the answer. As I understand the form was not submitted completely. Because $mform->issubmited() is returning false.