PHP quiz_has_feedback函数代码示例

 /**
  * Returns a list of quizzes in a provided list of courses,
  * if no list is provided all quizzes that the user can view will be returned.
  *
  * @param array $courseids Array of course ids
  * @return array of quizzes details
  * @since Moodle 3.1
  */
 public static function get_quizzes_by_courses($courseids = array())
 {
     global $USER;
     $warnings = array();
     $returnedquizzes = array();
     $params = array('courseids' => $courseids);
     $params = self::validate_parameters(self::get_quizzes_by_courses_parameters(), $params);
     $mycourses = array();
     if (empty($params['courseids'])) {
         $mycourses = enrol_get_my_courses();
         $params['courseids'] = array_keys($mycourses);
     }
     // Ensure there are courseids to loop through.
     if (!empty($params['courseids'])) {
         list($courses, $warnings) = external_util::validate_courses($params['courseids'], $mycourses);
         // Get the quizzes in this course, this function checks users visibility permissions.
         // We can avoid then additional validate_context calls.
         $quizzes = get_all_instances_in_courses("quiz", $courses);
         foreach ($quizzes as $quiz) {
             $context = context_module::instance($quiz->coursemodule);
             // Update quiz with override information.
             $quiz = quiz_update_effective_access($quiz, $USER->id);
             // Entry to return.
             $quizdetails = array();
             // First, we return information that any user can see in the web interface.
             $quizdetails['id'] = $quiz->id;
             $quizdetails['coursemodule'] = $quiz->coursemodule;
             $quizdetails['course'] = $quiz->course;
             $quizdetails['name'] = external_format_string($quiz->name, $context->id);
             if (has_capability('mod/quiz:view', $context)) {
                 // Format intro.
                 list($quizdetails['intro'], $quizdetails['introformat']) = external_format_text($quiz->intro, $quiz->introformat, $context->id, 'mod_quiz', 'intro', null);
                 $viewablefields = array('timeopen', 'timeclose', 'grademethod', 'section', 'visible', 'groupmode', 'groupingid');
                 $timenow = time();
                 $quizobj = quiz::create($quiz->id, $USER->id);
                 $accessmanager = new quiz_access_manager($quizobj, $timenow, has_capability('mod/quiz:ignoretimelimits', $context, null, false));
                 // Fields the user could see if have access to the quiz.
                 if (!$accessmanager->prevent_access()) {
                     // Some times this function returns just empty.
                     $hasfeedback = quiz_has_feedback($quiz);
                     $quizdetails['hasfeedback'] = !empty($hasfeedback) ? 1 : 0;
                     $quizdetails['hasquestions'] = (int) $quizobj->has_questions();
                     $quizdetails['autosaveperiod'] = get_config('quiz', 'autosaveperiod');
                     $additionalfields = array('timelimit', 'attempts', 'attemptonlast', 'grademethod', 'decimalpoints', 'questiondecimalpoints', 'reviewattempt', 'reviewcorrectness', 'reviewmarks', 'reviewspecificfeedback', 'reviewgeneralfeedback', 'reviewrightanswer', 'reviewoverallfeedback', 'questionsperpage', 'navmethod', 'sumgrades', 'grade', 'browsersecurity', 'delay1', 'delay2', 'showuserpicture', 'showblocks', 'completionattemptsexhausted', 'completionpass', 'overduehandling', 'graceperiod', 'preferredbehaviour', 'canredoquestions');
                     $viewablefields = array_merge($viewablefields, $additionalfields);
                 }
                 // Fields only for managers.
                 if (has_capability('moodle/course:manageactivities', $context)) {
                     $additionalfields = array('shuffleanswers', 'timecreated', 'timemodified', 'password', 'subnet');
                     $viewablefields = array_merge($viewablefields, $additionalfields);
                 }
                 foreach ($viewablefields as $field) {
                     $quizdetails[$field] = $quiz->{$field};
                 }
             }
             $returnedquizzes[] = $quizdetails;
         }
     }
     $result = array();
     $result['quizzes'] = $returnedquizzes;
     $result['warnings'] = $warnings;
     return $result;
 }

$viewobj->accessmanager = $accessmanager;
$viewobj->canreviewmine = $canreviewmine;

// Print table with existing attempts
if ($attempts) {
    // Work out which columns we need, taking account what data is available in each attempt.
    list($someoptions, $alloptions) = quiz_get_combined_reviewoptions($quiz, $attempts, $context);

    $viewobj->attemptcolumn = $quiz->attempts != 1;

    $viewobj->gradecolumn = $someoptions->marks >= question_display_options::MARK_AND_MAX &&
            quiz_has_grades($quiz);
    $viewobj->markcolumn = $viewobj->gradecolumn && ($quiz->grade != $quiz->sumgrades);
    $viewobj->overallstats = $lastfinishedattempt && $alloptions->marks >= question_display_options::MARK_AND_MAX;

    $viewobj->feedbackcolumn = quiz_has_feedback($quiz) && $alloptions->overallfeedback;
} else {
    $viewobj->attemptcolumn = 1;
}

$viewobj->timenow = $timenow;
$viewobj->numattempts = $numattempts;
$viewobj->mygrade = $mygrade;
$viewobj->moreattempts = $unfinished ||
        !$accessmanager->is_finished($numattempts, $lastfinishedattempt);
$viewobj->mygradeoverridden = $mygradeoverridden;
$viewobj->gradebookfeedback = $gradebookfeedback;
$viewobj->lastfinishedattempt = $lastfinishedattempt;
$viewobj->canedit = has_capability('mod/quiz:manage', $context);
$viewobj->editurl = new moodle_url('/mod/quiz/edit.php', array('cmid' => $cm->id));
$viewobj->backtocourseurl = new moodle_url('/course/view.php', array('id' => $course->id));

 /**
  * Add all the grade and feedback columns, if applicable, to the $columns
  * and $headers arrays.
  * @param object $quiz the quiz settings.
  * @param bool $usercanseegrades whether the user is allowed to see grades for this quiz.
  * @param array $columns the list of columns. Added to.
  * @param array $headers the columns headings. Added to.
  * @param bool $includefeedback whether to include the feedbacktext columns
  */
 protected function add_grade_columns($quiz, $usercanseegrades, &$columns, &$headers, $includefeedback = true)
 {
     if ($usercanseegrades) {
         $columns[] = 'sumgrades';
         $headers[] = get_string('grade', 'quiz') . '/' . quiz_format_grade($quiz, $quiz->grade);
     }
     if ($includefeedback && quiz_has_feedback($quiz)) {
         $columns[] = 'feedbacktext';
         $headers[] = get_string('feedback', 'quiz');
     }
 }

 /**
  * Display the report.
  */
 function display($quiz, $cm, $course)
 {
     global $CFG, $COURSE, $DB, $PAGE, $OUTPUT;
     $context = get_context_instance(CONTEXT_MODULE, $cm->id);
     // Work out some display options - whether there is feedback, and whether scores should be shown.
     $hasfeedback = quiz_has_feedback($quiz);
     $fakeattempt = new stdClass();
     $fakeattempt->preview = false;
     $fakeattempt->timefinish = $quiz->timeopen;
     $fakeattempt->userid = 0;
     $reviewoptions = quiz_get_reviewoptions($quiz, $fakeattempt, $context);
     $showgrades = quiz_has_grades($quiz) && $reviewoptions->scores;
     $download = optional_param('download', '', PARAM_ALPHA);
     if ($attemptids = optional_param('attemptid', array(), PARAM_INT)) {
         //attempts need to be deleted
         require_capability('mod/quiz:deleteattempts', $context);
         $attemptids = optional_param('attemptid', array(), PARAM_INT);
         foreach ($attemptids as $attemptid) {
             add_to_log($course->id, 'quiz', 'delete attempt', 'report.php?id=' . $cm->id, $attemptid, $cm->id);
             quiz_delete_attempt($attemptid, $quiz);
         }
         //No need for a redirect, any attemptids that do not exist are ignored.
         //So no problem if the user refreshes and tries to delete the same attempts
         //twice.
     }
     $pageoptions = array();
     $pageoptions['id'] = $cm->id;
     $pageoptions['q'] = $quiz->id;
     $pageoptions['mode'] = 'responses';
     $reporturl = new moodle_url($CFG->wwwroot . '/mod/quiz/report.php', $pageoptions);
     $qmsubselect = quiz_report_qm_filter_select($quiz);
     /// find out current groups mode
     $currentgroup = groups_get_activity_group($cm, true);
     $mform = new mod_quiz_report_responses_settings($reporturl, array('qmsubselect' => $qmsubselect, 'quiz' => $quiz, 'currentgroup' => $currentgroup));
     if ($fromform = $mform->get_data()) {
         $attemptsmode = $fromform->attemptsmode;
         if ($qmsubselect) {
             //control is not on the form if
             //the grading method is not set
             //to grade one attempt per user eg. for average attempt grade.
             $qmfilter = $fromform->qmfilter;
         } else {
             $qmfilter = 0;
         }
         set_user_preference('quiz_report_pagesize', $fromform->pagesize);
         $pagesize = $fromform->pagesize;
     } else {
         $qmfilter = optional_param('qmfilter', 0, PARAM_INT);
         $attemptsmode = optional_param('attemptsmode', null, PARAM_INT);
         if ($attemptsmode === null) {
             //default
             $attemptsmode = QUIZ_REPORT_ATTEMPTS_ALL;
         } else {
             if ($currentgroup) {
                 //default for when a group is selected
                 if ($attemptsmode === null || $attemptsmode == QUIZ_REPORT_ATTEMPTS_ALL) {
                     $attemptsmode = QUIZ_REPORT_ATTEMPTS_STUDENTS_WITH;
                 }
             } else {
                 if (!$currentgroup && $course->id == SITEID) {
                     //force report on front page to show all, unless a group is selected.
                     $attemptsmode = QUIZ_REPORT_ATTEMPTS_ALL;
                 }
             }
         }
         $pagesize = get_user_preferences('quiz_report_pagesize', 0);
     }
     if ($pagesize < 1) {
         $pagesize = QUIZ_REPORT_DEFAULT_PAGE_SIZE;
     }
     // We only want to show the checkbox to delete attempts
     // if the user has permissions and if the report mode is showing attempts.
     $candelete = has_capability('mod/quiz:deleteattempts', $context) && $attemptsmode != QUIZ_REPORT_ATTEMPTS_STUDENTS_WITH_NO;
     $displayoptions = array();
     $displayoptions['attemptsmode'] = $attemptsmode;
     $displayoptions['qmfilter'] = $qmfilter;
     //work out the sql for this table.
     if (!($students = get_users_by_capability($context, array('mod/quiz:reviewmyattempts', 'mod/quiz:attempt'), '', '', '', '', '', '', false))) {
         $students = array();
     } else {
         $students = array_keys($students);
     }
     if (empty($currentgroup)) {
         // all users who can attempt quizzes
         $allowed = $students;
         $groupstudents = array();
     } else {
         // all users who can attempt quizzes and who are in the currently selected group
         if (!($groupstudents = get_users_by_capability($context, array('mod/quiz:reviewmyattempts', 'mod/quiz:attempt'), '', '', '', '', $currentgroup, '', false))) {
             $groupstudents = array();
         } else {
             $groupstudents = array_keys($groupstudents);
         }
         $allowed = $groupstudents;
     }
     $questions = quiz_report_load_questions($quiz);
     $table = new quiz_report_responses_table($quiz, $qmsubselect, $groupstudents, $students, $questions, $candelete, $reporturl, $displayoptions);
//.........这里部分代码省略.........

    /**
     * Display the report.
     */
    function display($quiz, $cm, $course) {
        global $CFG, $COURSE, $DB, $OUTPUT;

        $this->context = get_context_instance(CONTEXT_MODULE, $cm->id);

        // Work out some display options - whether there is feedback, and whether scores should be shown.
        $hasfeedback = quiz_has_feedback($quiz);
        $fakeattempt = new stdClass();
        $fakeattempt->preview = false;
        $fakeattempt->timefinish = $quiz->timeopen;
        $fakeattempt->userid = 0;
        $reviewoptions = quiz_get_reviewoptions($quiz, $fakeattempt, $this->context);
        $showgrades = quiz_has_grades($quiz) && $reviewoptions->scores;

        $download = optional_param('download', '', PARAM_ALPHA);

        /// find out current groups mode
        $currentgroup = groups_get_activity_group($cm, true);
        if (!$students = get_users_by_capability($this->context, array('mod/quiz:reviewmyattempts', 'mod/quiz:attempt'),'u.id,1','','','','','',false)) {
            $students = array();
        } else {
            $students = array_keys($students);
        }

        if (empty($currentgroup)) {
            // all users who can attempt quizzes
            $allowed = $students;
            $groupstudents = array();
        } else {
            // all users who can attempt quizzes and who are in the currently selected group
            if (!$groupstudents = get_users_by_capability($this->context, array('mod/quiz:reviewmyattempts', 'mod/quiz:attempt'),'u.id,1','','','',$currentgroup,'',false)) {
                $groupstudents = array();
            } else {
                $groupstudents = array_keys($groupstudents);
            }
            $allowed = $groupstudents;
        }

        $pageoptions = array();
        $pageoptions['id'] = $cm->id;
        $pageoptions['mode'] = 'overview';

        $reporturl = new moodle_url('/mod/quiz/report.php', $pageoptions);
        $qmsubselect = quiz_report_qm_filter_select($quiz);

        $mform = new mod_quiz_report_overview_settings($reporturl, array('qmsubselect'=> $qmsubselect, 'quiz'=>$quiz,
                                                             'currentgroup'=>$currentgroup, 'context'=>$this->context));
        if ($fromform = $mform->get_data()) {
            $regradeall = false;
            $regradealldry = false;
            $regradealldrydo = false;
            $attemptsmode = $fromform->attemptsmode;
            if ($qmsubselect) {
                //control is not on the form if
                //the grading method is not set
                //to grade one attempt per user eg. for average attempt grade.
                $qmfilter = $fromform->qmfilter;
            } else {
                $qmfilter = 0;
            }
            $regradefilter = $fromform->regradefilter;
            set_user_preference('quiz_report_overview_detailedmarks', $fromform->detailedmarks);
            set_user_preference('quiz_report_pagesize', $fromform->pagesize);
            $detailedmarks = $fromform->detailedmarks;
            $pagesize = $fromform->pagesize;
        } else {
            $regradeall  = optional_param('regradeall', 0, PARAM_BOOL);
            $regradealldry  = optional_param('regradealldry', 0, PARAM_BOOL);
            $regradealldrydo  = optional_param('regradealldrydo', 0, PARAM_BOOL);
            $attemptsmode = optional_param('attemptsmode', null, PARAM_INT);
            if ($qmsubselect) {
                $qmfilter = optional_param('qmfilter', 0, PARAM_INT);
            } else {
                $qmfilter = 0;
            }
            $regradefilter = optional_param('regradefilter', 0, PARAM_INT);

            $detailedmarks = get_user_preferences('quiz_report_overview_detailedmarks', 1);
            $pagesize = get_user_preferences('quiz_report_pagesize', 0);
        }
        if ($currentgroup) {
            //default for when a group is selected
            if ($attemptsmode === null  || $attemptsmode == QUIZ_REPORT_ATTEMPTS_ALL) {
                $attemptsmode = QUIZ_REPORT_ATTEMPTS_STUDENTS_WITH;
            }
        } else if (!$currentgroup && $course->id == SITEID) {
            //force report on front page to show all, unless a group is selected.
            $attemptsmode = QUIZ_REPORT_ATTEMPTS_ALL;
        } else if ($attemptsmode === null) {
            //default
            $attemptsmode = QUIZ_REPORT_ATTEMPTS_ALL;
        }
        if (!$reviewoptions->scores) {
            $detailedmarks = 0;
        }
        if ($pagesize < 1) {
            $pagesize = QUIZ_REPORT_DEFAULT_PAGE_SIZE;
//.........这里部分代码省略.........

 /**
  * Display the report.
  */
 function display($quiz, $cm, $course)
 {
     global $CFG, $db;
     // Define some strings
     $strreallydel = addslashes(get_string('deleteattemptcheck', 'quiz'));
     $strtimeformat = get_string('strftimedatetime');
     $strreviewquestion = get_string('reviewresponse', 'quiz');
     $context = get_context_instance(CONTEXT_MODULE, $cm->id);
     // Only print headers if not asked to download data
     if (!($download = optional_param('download', NULL))) {
         $this->print_header_and_tabs($cm, $course, $quiz, "overview");
     }
     if ($attemptids = optional_param('attemptid', array(), PARAM_INT)) {
         //attempts need to be deleted
         require_capability('mod/quiz:deleteattempts', $context);
         $attemptids = optional_param('attemptid', array(), PARAM_INT);
         foreach ($attemptids as $attemptid) {
             add_to_log($course->id, 'quiz', 'delete attempt', 'report.php?id=' . $cm->id, $attemptid, $cm->id);
             quiz_delete_attempt($attemptid, $quiz);
         }
         //No need for a redirect, any attemptids that do not exist are ignored.
         //So no problem if the user refreshes and tries to delete the same attempts
         //twice.
     }
     // Work out some display options - whether there is feedback, and whether scores should be shown.
     $hasfeedback = quiz_has_feedback($quiz->id) && $quiz->grade > 1.0E-7 && $quiz->sumgrades > 1.0E-7;
     $fakeattempt = new stdClass();
     $fakeattempt->preview = false;
     $fakeattempt->timefinish = $quiz->timeopen;
     $reviewoptions = quiz_get_reviewoptions($quiz, $fakeattempt, $context);
     $showgrades = $quiz->grade && $quiz->sumgrades && $reviewoptions->scores;
     $pageoptions = array();
     $pageoptions['id'] = $cm->id;
     $pageoptions['q'] = $quiz->id;
     $pageoptions['mode'] = 'overview';
     /// find out current groups mode
     $currentgroup = groups_get_activity_group($cm, true);
     $reporturl = new moodle_url($CFG->wwwroot . '/mod/quiz/report.php', $pageoptions);
     $qmsubselect = quiz_report_qm_filter_select($quiz);
     $mform = new mod_quiz_report_overview_settings($reporturl, compact('qmsubselect', 'quiz', 'currentgroup'));
     if ($fromform = $mform->get_data()) {
         $attemptsmode = $fromform->attemptsmode;
         if ($qmsubselect) {
             //control is not on the form if
             //the grading method is not set
             //to grade one attempt per user eg. for average attempt grade.
             $qmfilter = $fromform->qmfilter;
         } else {
             $qmfilter = 0;
         }
         set_user_preference('quiz_report_overview_detailedmarks', $fromform->detailedmarks);
         set_user_preference('quiz_report_pagesize', $fromform->pagesize);
         $detailedmarks = $fromform->detailedmarks;
         $pagesize = $fromform->pagesize;
     } else {
         $qmfilter = optional_param('qmfilter', 0, PARAM_INT);
         $attemptsmode = optional_param('attemptsmode', QUIZ_REPORT_ATTEMPTS_ALL, PARAM_INT);
         $detailedmarks = get_user_preferences('quiz_report_overview_detailedmarks', 1);
         $pagesize = get_user_preferences('quiz_report_pagesize', 0);
     }
     if ($attemptsmode == QUIZ_REPORT_ATTEMPTS_ALL && $currentgroup) {
         $attemptsmode = QUIZ_REPORT_ATTEMPTS_STUDENTS_WITH;
     }
     if (!$reviewoptions->scores) {
         $detailedmarks = 0;
     }
     if ($pagesize < 1) {
         $pagesize = QUIZ_REPORT_DEFAULT_PAGE_SIZE;
     }
     // We only want to show the checkbox to delete attempts
     // if the user has permissions and if the report mode is showing attempts.
     $candelete = has_capability('mod/quiz:deleteattempts', $context) && $attemptsmode != QUIZ_REPORT_ATTEMPTS_STUDENTS_WITH_NO;
     $displayoptions = array();
     $displayoptions['attemptsmode'] = $attemptsmode;
     $displayoptions['qmfilter'] = $qmfilter;
     $reporturlwithdisplayoptions = new moodle_url($CFG->wwwroot . '/mod/quiz/report.php', $pageoptions + $displayoptions);
     if ($groupmode = groups_get_activity_groupmode($cm)) {
         // Groups are being used
         if (!$download) {
             groups_print_activity_menu($cm, $reporturlwithdisplayoptions->out());
         }
     }
     // Print information on the number of existing attempts
     if (!$download) {
         //do not print notices when downloading
         if ($strattemptnum = quiz_num_attempt_summary($quiz, $cm, true, $currentgroup)) {
             echo '<div class="quizattemptcounts">' . $strattemptnum . '</div>';
         }
     }
     $nostudents = false;
     if (!($students = get_users_by_capability($context, array('mod/quiz:reviewmyattempts', 'mod/quiz:attempt'), '', '', '', '', '', '', false))) {
         notify(get_string('nostudentsyet'));
         $nostudents = true;
         $studentslist = '';
     } else {
         $studentslist = join(',', array_keys($students));
     }
//.........这里部分代码省略.........

            $mygradeoverridden = true;
        }
        if (!empty($grade->str_feedback)) {
            $gradebookfeedback = $grade->str_feedback;
        }
    }
}
// Print table with existing attempts
if ($attempts) {
    print_heading(get_string('summaryofattempts', 'quiz'));
    // Work out which columns we need, taking account what data is available in each attempt.
    list($someoptions, $alloptions) = quiz_get_combined_reviewoptions($quiz, $attempts, $context);
    $gradecolumn = $someoptions->scores && $quiz->grade && $quiz->sumgrades;
    $markcolumn = $gradecolumn && $quiz->grade != $quiz->sumgrades;
    $overallstats = $alloptions->scores;
    $feedbackcolumn = quiz_has_feedback($quiz->id);
    $overallfeedback = $feedbackcolumn && $alloptions->overallfeedback;
    // Prepare table header
    $table->class = 'generaltable quizattemptsummary';
    $table->head = array(get_string('attempt', 'quiz'), get_string('timecompleted', 'quiz'));
    $table->align = array('center', 'left');
    $table->size = array('', '');
    if ($markcolumn) {
        $table->head[] = get_string('marks', 'quiz') . " / {$quiz->sumgrades}";
        $table->align[] = 'center';
        $table->size[] = '';
    }
    if ($gradecolumn) {
        $table->head[] = get_string('grade') . " / {$quiz->grade}";
        $table->align[] = 'center';
        $table->size[] = '';

$navlinks[] = array('name' => $strquizzes, 'link' => '', 'type' => 'activity');
$navigation = build_navigation($navlinks);
print_header_simple($strquizzes, '', $navigation, '', '', true, $streditquestions, navmenu($course));
// Get all the appropriate data
if (!($quizzes = get_all_instances_in_course("quiz", $course))) {
    notice(get_string('thereareno', 'moodle', $strquizzes), "../../course/view.php?id={$course->id}");
    die;
}
// Check if we need the closing date header
$showclosingheader = false;
$showfeedback = false;
foreach ($quizzes as $quiz) {
    if ($quiz->timeclose != 0) {
        $showclosingheader = true;
    }
    if (quiz_has_feedback($quiz->id)) {
        $showfeedback = true;
    }
}
// Configure table for displaying the list of instances.
$headings = array(get_string('name'));
$align = array('left');
if ($showclosingheader) {
    array_push($headings, get_string('quizcloses', 'quiz'));
    array_push($align, 'left');
}
if ($course->format == 'weeks' or $course->format == 'weekscss') {
    array_unshift($headings, get_string('week'));
} else {
    array_unshift($headings, get_string('section'));
}

$navlinks[] = array('name' => $strquizzes, 'link' => '', 'type' => 'activity');
$navigation = build_navigation($navlinks);
print_header_simple($strquizzes, '', $navigation, '', '', true, $streditquestions, navmenu($course));
// Get all the appropriate data
if (!($quizzes = get_all_instances_in_course("quiz", $course))) {
    notice(get_string('thereareno', 'moodle', $strquizzes), "../../course/view.php?id={$course->id}");
    die;
}
// Check if we need the closing date header
$showclosingheader = false;
$showfeedback = false;
foreach ($quizzes as $quiz) {
    if ($quiz->timeclose != 0) {
        $showclosingheader = true;
    }
    if (quiz_has_feedback($quiz)) {
        $showfeedback = true;
    }
}
// Configure table for displaying the list of instances.
$headings = array(get_string('name'));
$align = array('left');
if ($showclosingheader) {
    array_push($headings, get_string('quizcloses', 'quiz'));
    array_push($align, 'left');
}
if ($course->format == 'weeks' or $course->format == 'weekscss') {
    array_unshift($headings, get_string('week'));
} else {
    array_unshift($headings, get_string('section'));
}

 /**
  * Add all the grade and feedback columns, if applicable, to the $columns
  * and $headers arrays.
  * @param object $quiz the quiz settings.
  * @param array $columns the list of columns. Added to.
  * @param array $headers the columns headings. Added to.
  */
 protected function add_grade_columns($quiz, &$columns, &$headers)
 {
     if ($this->should_show_grades($quiz)) {
         $columns[] = 'sumgrades';
         $headers[] = get_string('grade', 'quiz') . '/' . quiz_format_grade($quiz, $quiz->grade);
     }
     if (quiz_has_feedback($quiz)) {
         $columns[] = 'feedbacktext';
         $headers[] = get_string('feedback', 'quiz');
     }
 }