public function definition() {
        $mform = $this->_form;

        $mform->addElement('select', 'size', get_string('size', 'tool_generator'),
                tool_generator_course_backend::get_size_choices());
        $mform->setDefault('size', tool_generator_course_backend::DEFAULT_SIZE);

        $mform->addElement('text', 'shortname', get_string('shortnamecourse'));
        $mform->addRule('shortname', get_string('missingshortname'), 'required', null, 'client');
        $mform->setType('shortname', PARAM_TEXT);

        $mform->addElement('text', 'fullname', get_string('fullnamecourse'));
        $mform->setType('fullname', PARAM_TEXT);

        $mform->addElement('editor', 'summary', get_string('coursesummary'));
        $mform->setType('summary', PARAM_RAW);

        $mform->addElement('submit', 'submit', get_string('createcourse', 'tool_generator'));
    }