moodle/question/category_form.php

<?php

if (!defined('MOODLE_INTERNAL')) {
    die('Direct access to this script is forbidden.');    ///  It must be included from a Moodle page
}

require_once($CFG->libdir.'/formslib.php');

class question_category_edit_form extends moodleform {

    function definition() {
        global $CFG, $DB;
        $mform    =& $this->_form;

        $contexts   = $this->_customdata['contexts'];
        $currentcat   = $this->_customdata['currentcat'];
//--------------------------------------------------------------------------------
        $mform->addElement('header', 'categoryheader', get_string('addcategory', 'quiz'));

        $questioncategoryel = $mform->addElement('questioncategory', 'parent', get_string('parentcategory', 'question'),
                    array('contexts'=>$contexts, 'top'=>true, 'currentcat'=>$currentcat, 'nochildrenof'=>$currentcat));
        $mform->setType('parent', PARAM_SEQUENCE);
        if (question_is_only_toplevel_category_in_context($currentcat)) {
            $mform->hardFreeze('parent');
        }
        $mform->addHelpButton('parent', 'parentcategory', 'question');

        $mform->addElement('text','name', get_string('name'),'maxlength="254" size="50"');
        $mform->setDefault('name', '');
        $mform->addRule('name', get_string('categorynamecantbeblank', 'quiz'), 'required', null, 'client');
        $mform->setType('name', PARAM_MULTILANG);

        $mform->addElement('textarea', 'info', get_string('categoryinfo', 'quiz'), array('rows'=> '10', 'cols'=>'45'));
        $mform->setDefault('info', '');
        $mform->setType('info', PARAM_MULTILANG);
//--------------------------------------------------------------------------------
        $this->add_action_buttons(false, get_string('addcategory', 'quiz'));
//--------------------------------------------------------------------------------
        $mform->addElement('hidden', 'id', 0);
        $mform->setType('id', PARAM_INT);
    }
}