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  • Bug fixes for general core bugs in 3.11.x will end 14 Nov 2022 (12 months plus 6 months extension).
  • Bug fixes for security issues in 3.11.x will end 13 Nov 2023 (18 months plus 12 months extension).
  • PHP version: minimum PHP 7.3.0 Note: minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is supported too.
  •    1  <?php
       2  // This file is part of Moodle - http://moodle.org/
       3  //
       4  // Moodle is free software: you can redistribute it and/or modify
       5  // it under the terms of the GNU General Public License as published by
       6  // the Free Software Foundation, either version 3 of the License, or
       7  // (at your option) any later version.
       8  //
       9  // Moodle is distributed in the hope that it will be useful,
      10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
      11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12  // GNU General Public License for more details.
      13  //
      14  // You should have received a copy of the GNU General Public License
      15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
      16  
      17  /**
      18   * Question behaviour that is like the interactive behaviour, but where the
      19   * student is credited for parts of the question they got right on earlier tries.
      20   *
      21   * @package    qbehaviour
      22   * @subpackage interactivecountback
      23   * @copyright  2009 The Open University
      24   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
      25   */
      26  
      27  
      28  defined('MOODLE_INTERNAL') || die();
      29  
      30  require_once (__DIR__ . '/../interactive/behaviour.php');
      31  
      32  
      33  /**
      34   * Question behaviour for interactive mode with count-back scoring.
      35   *
      36   * As an example, suppose we have a matching question with 4 parts, and 3 tries
      37   * (penalty 1/3), and the question is worth 12 marks (so, 3 marks for each part).
      38   * Suppose also that:
      39   *  - on the first try, the student gets the first two parts right, and the
      40   *    other two wrong.
      41   *  - on the second try, they are sure they got the first part right, so keep
      42   *    their answer the same, but they change their answer to the second part.
      43   *    They also get the answer to the thrid part right on this try, but still
      44   *    get the 4th part wrong.
      45   *  - On the final try, they get the first 3 parts right, but the 4th part still
      46   *    wrong.
      47   * We want to grade them as follows.
      48   *  - For the first part, they were right first time, and did not change their
      49   *    answer, so we credit that part as right first time: 3/3
      50   *  - For the second part, although they were right first time, they then changed
      51   *    their mind, an only finally got it right on the third try, so 1/3.
      52   *  - For the third part, they got it right on the second try, and then did not
      53   *    change their answer, so 2/3.
      54   *  - For the last part, they were wrong at the last try, so 0/3.
      55   * So, total mark is 6/12. (Really, a fraction of 0.5.)
      56   *
      57   * Of course, the details of the grading are actually up to the particular
      58   * question type. The point is that the final grade can take into account all
      59   * of the tries the student made.
      60   *
      61   * @copyright  2009 The Open University
      62   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
      63   */
      64  class qbehaviour_interactivecountback extends qbehaviour_interactive {
      65  
      66      public function is_compatible_question(question_definition $question) {
      67          return $question instanceof question_automatically_gradable_with_countback;
      68      }
      69  
      70      protected function adjust_fraction($fraction, question_attempt_pending_step $pendingstep) {
      71          $totaltries = $this->qa->get_step(0)->get_behaviour_var('_triesleft');
      72  
      73          $responses = array();
      74          $lastsave = array();
      75          foreach ($this->qa->get_step_iterator() as $step) {
      76              if ($step->has_behaviour_var('submit') &&
      77                      $step->get_state() != question_state::$invalid) {
      78                  $responses[] = $step->get_qt_data();
      79                  $lastsave = array();
      80              } else {
      81                  $lastsave = $step->get_qt_data();
      82              }
      83          }
      84          $lastresponse = $pendingstep->get_qt_data();
      85          if (!empty($lastresponse)) {
      86              $responses[] = $lastresponse;
      87          } else if (!empty($lastsave)) {
      88              $responses[] = $lastsave;
      89          }
      90  
      91          return $this->question->compute_final_grade($responses, $totaltries);
      92      }
      93  }