Search moodle.org's
Developer Documentation

See Release Notes

  • Bug fixes for general core bugs in 4.2.x will end 22 April 2024 (12 months).
  • Bug fixes for security issues in 4.2.x will end 7 October 2024 (18 months).
  • PHP version: minimum PHP 8.0.0 Note: minimum PHP version has increased since Moodle 4.1. PHP 8.1.x is supported too.
<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.


/**
 * Multianswer question definition class.
 *
 * @package    qtype
 * @subpackage multianswer
 * @copyright  2010 Pierre Pichet
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

require_once($CFG->dirroot . '/question/type/questionbase.php');
require_once($CFG->dirroot . '/question/type/shortanswer/question.php');
require_once($CFG->dirroot . '/question/type/numerical/question.php');
require_once($CFG->dirroot . '/question/type/multichoice/question.php');


/**
 * Represents a multianswer question.
 *
 * A multi-answer question is made of of several subquestions of various types.
 * You can think of it as an application of the composite pattern to qusetion
 * types.
 *
 * @copyright  2010 Pierre Pichet
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class qtype_multianswer_question extends question_graded_automatically_with_countback {
    /** @var array of question_graded_automatically. */
    public $subquestions = array();

    /**
     * @var array place number => insex in the $subquestions array. Places are
     * numbered from 1.
     */
    public $places;

    /**
     * @var array of strings, one longer than $places, which is achieved by
     * indexing from 0. The bits of question text that go between the subquestions.
     */
    public $textfragments;

    /**
     * Get a question_attempt_step_subquestion_adapter
     * @param question_attempt_step $step the step to adapt.
     * @param int $i the subquestion index.
     * @return question_attempt_step_subquestion_adapter.
     */
    protected function get_substep($step, $i) {
        return new question_attempt_step_subquestion_adapter($step, 'sub' . $i . '_');
    }

    public function start_attempt(question_attempt_step $step, $variant) {
        foreach ($this->subquestions as $i => $subq) {
            $subq->start_attempt($this->get_substep($step, $i), $variant);
        }
    }

    public function apply_attempt_state(question_attempt_step $step) {
        foreach ($this->subquestions as $i => $subq) {
            $subq->apply_attempt_state($this->get_substep($step, $i));
        }
    }

    public function validate_can_regrade_with_other_version(question_definition $otherversion): ?string {
        $basemessage = parent::validate_can_regrade_with_other_version($otherversion);
        if ($basemessage) {
            return $basemessage;
        }

        if (count($this->subquestions) != count($otherversion->subquestions)) {
            return get_string('regradeissuenumsubquestionschanged', 'qtype_multianswer');
        }

        foreach ($this->subquestions as $i => $subq) {
            $subqmessage = $subq->validate_can_regrade_with_other_version($otherversion->subquestions[$i]);
            if ($subqmessage) {
                return $subqmessage;
            }
        }

        return null;
    }

    public function update_attempt_state_data_for_new_version(
            question_attempt_step $oldstep, question_definition $oldquestion) {
        parent::update_attempt_state_data_for_new_version($oldstep, $oldquestion);

        $result = [];
        foreach ($this->subquestions as $i => $subq) {
            $substep = $this->get_substep($oldstep, $i);
            $statedata = $subq->update_attempt_state_data_for_new_version(
                    $substep, $oldquestion->subquestions[$i]);
            foreach ($statedata as $name => $value) {
                $result[$substep->add_prefix($name)] = $value;
            }
        }

        return $result;
    }

    public function get_question_summary() {
        $summary = $this->html_to_text($this->questiontext, $this->questiontextformat);
        foreach ($this->subquestions as $i => $subq) {
            switch ($subq->qtype->name()) {
                case 'multichoice':
                    $choices = array();
                    $dummyqa = new question_attempt($subq, $this->contextid);
                    foreach ($subq->get_order($dummyqa) as $ansid) {
                        $choices[] = $this->html_to_text($subq->answers[$ansid]->answer,
                                $subq->answers[$ansid]->answerformat);
                    }
                    $answerbit = '{' . implode('; ', $choices) . '}';
                    break;
                case 'numerical':
                case 'shortanswer':
                    $answerbit = '_____';
                    break;
                default:
                    $answerbit = '{ERR unknown sub-question type}';
            }
            $summary = str_replace('{#' . $i . '}', $answerbit, $summary);
        }
        return $summary;
    }

    public function get_min_fraction() {
        $fractionsum = 0;
        $fractionmax = 0;
        foreach ($this->subquestions as $i => $subq) {
            $fractionmax += $subq->defaultmark;
            $fractionsum += $subq->defaultmark * $subq->get_min_fraction();
        }
> if (empty($fractionsum)) { return $fractionsum / (!empty($this->subquestions) ? $fractionmax : 1); > return 0; } > }
public function get_max_fraction() { $fractionsum = 0; $fractionmax = 0; foreach ($this->subquestions as $i => $subq) { $fractionmax += $subq->defaultmark; $fractionsum += $subq->defaultmark * $subq->get_max_fraction(); }
> if (empty($fractionsum)) { return $fractionsum / (!empty($this->subquestions) ? $fractionmax : 1); > return 1; } > }
public function get_expected_data() { $expected = array(); foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); foreach ($subq->get_expected_data() as $name => $type) { if ($subq->qtype->name() == 'multichoice' && $subq->layout == qtype_multichoice_base::LAYOUT_DROPDOWN) { // Hack or MC inline does not work. $expected[$substep->add_prefix($name)] = PARAM_RAW; } else { $expected[$substep->add_prefix($name)] = $type; } } } return $expected; } public function get_correct_response() { $right = array(); foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); foreach ($subq->get_correct_response() as $name => $type) { $right[$substep->add_prefix($name)] = $type; } } return $right; } public function prepare_simulated_post_data($simulatedresponse) { $postdata = array(); foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); foreach ($subq->prepare_simulated_post_data($simulatedresponse[$i]) as $name => $value) { $postdata[$substep->add_prefix($name)] = $value; } } return $postdata; } public function get_student_response_values_for_simulation($postdata) { $simulatedresponse = array(); foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); $subqpostdata = $substep->filter_array($postdata); $subqsimulatedresponse = $subq->get_student_response_values_for_simulation($subqpostdata); foreach ($subqsimulatedresponse as $subresponsekey => $responsevalue) { $simulatedresponse[$i.'.'.$subresponsekey] = $responsevalue; } } ksort($simulatedresponse); return $simulatedresponse; } public function is_complete_response(array $response) { foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); if (!$subq->is_complete_response($substep->filter_array($response))) { return false; } } return true; } public function is_gradable_response(array $response) { foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); if ($subq->is_gradable_response($substep->filter_array($response))) { return true; } } return false; } public function is_same_response(array $prevresponse, array $newresponse) { foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); if (!$subq->is_same_response($substep->filter_array($prevresponse), $substep->filter_array($newresponse))) { return false; } } return true; } public function get_validation_error(array $response) { if ($this->is_complete_response($response)) { return ''; } return get_string('pleaseananswerallparts', 'qtype_multianswer'); } /** * Used by grade_response to combine the states of the subquestions. * The combined state is accumulates in $overallstate. That will be right * if all the separate states are right; and wrong if all the separate states * are wrong, otherwise, it will be partially right. * @param question_state $overallstate the result so far. * @param question_state $newstate the new state to add to the combination. * @return question_state the new combined state. */ protected function combine_states($overallstate, $newstate) { if (is_null($overallstate)) { return $newstate; } else if ($overallstate == question_state::$gaveup && $newstate == question_state::$gaveup) { return question_state::$gaveup; } else if ($overallstate == question_state::$gaveup && $newstate == question_state::$gradedwrong) { return question_state::$gradedwrong; } else if ($overallstate == question_state::$gradedwrong && $newstate == question_state::$gaveup) { return question_state::$gradedwrong; } else if ($overallstate == question_state::$gradedwrong && $newstate == question_state::$gradedwrong) { return question_state::$gradedwrong; } else if ($overallstate == question_state::$gradedright && $newstate == question_state::$gradedright) { return question_state::$gradedright; } else { return question_state::$gradedpartial; } } public function grade_response(array $response) { $overallstate = null; $fractionsum = 0; $fractionmax = 0; foreach ($this->subquestions as $i => $subq) { $fractionmax += $subq->defaultmark; $substep = $this->get_substep(null, $i); $subresp = $substep->filter_array($response); if (!$subq->is_gradable_response($subresp)) { $overallstate = $this->combine_states($overallstate, question_state::$gaveup); } else { list($subfraction, $newstate) = $subq->grade_response($subresp); $fractionsum += $subfraction * $subq->defaultmark; $overallstate = $this->combine_states($overallstate, $newstate); }
> } } > if (empty($fractionmax)) { return array($fractionsum / $fractionmax, $overallstate); > return array(null, $overallstate ?? question_state::$finished);
} public function clear_wrong_from_response(array $response) { foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); $subresp = $substep->filter_array($response); list($subfraction, $newstate) = $subq->grade_response($subresp); if ($newstate != question_state::$gradedright) { foreach ($subresp as $ind => $resp) { if ($subq->qtype == 'multichoice' && ($subq->layout == qtype_multichoice_base::LAYOUT_VERTICAL || $subq->layout == qtype_multichoice_base::LAYOUT_HORIZONTAL)) { $response[$substep->add_prefix($ind)] = '-1'; } else { $response[$substep->add_prefix($ind)] = ''; } } } } return $response; } public function get_num_parts_right(array $response) { $numright = 0; foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); $subresp = $substep->filter_array($response); list($subfraction, $newstate) = $subq->grade_response($subresp); if ($newstate == question_state::$gradedright) { $numright += 1; } } return array($numright, count($this->subquestions)); } public function compute_final_grade($responses, $totaltries) { $fractionsum = 0; $fractionmax = 0; foreach ($this->subquestions as $i => $subq) { $fractionmax += $subq->defaultmark; $lastresponse = array(); $lastchange = 0; $subfraction = 0; foreach ($responses as $responseindex => $response) { $substep = $this->get_substep(null, $i); $subresp = $substep->filter_array($response); if ($subq->is_same_response($lastresponse, $subresp)) { continue; } $lastresponse = $subresp; $lastchange = $responseindex; list($subfraction, $newstate) = $subq->grade_response($subresp); } $fractionsum += $subq->defaultmark * max(0, $subfraction - $lastchange * $this->penalty); } return $fractionsum / $fractionmax; } public function summarise_response(array $response) { $summary = array(); foreach ($this->subquestions as $i => $subq) { $substep = $this->get_substep(null, $i); $a = new stdClass(); $a->i = $i; $a->response = $subq->summarise_response($substep->filter_array($response)); $summary[] = get_string('subqresponse', 'qtype_multianswer', $a); } return implode('; ', $summary); } public function check_file_access($qa, $options, $component, $filearea, $args, $forcedownload) { if ($component == 'question' && $filearea == 'answer') { return true; } else if ($component == 'question' && $filearea == 'answerfeedback') { // Full logic to control which feedbacks a student can see is too complex. // Just allow access to all images. There is a theoretical chance the // students could see files they are not meant to see by guessing URLs, // but it is remote. return $options->feedback; } else if ($component == 'question' && $filearea == 'hint') { return $this->check_hint_file_access($qa, $options, $args); } else { return parent::check_file_access($qa, $options, $component, $filearea, $args, $forcedownload); } } /** * Return the question settings that define this question as structured data. * * @param question_attempt $qa the current attempt for which we are exporting the settings. * @param question_display_options $options the question display options which say which aspects of the question * should be visible. * @return mixed structure representing the question settings. In web services, this will be JSON-encoded. */ public function get_question_definition_for_external_rendering(question_attempt $qa, question_display_options $options) { // Empty implementation for now in order to avoid debugging in core questions (generated in the parent class), // ideally, we should return as much as settings as possible (depending on the state and display options). return null; } }