lib/form/templatable_form_element.php

   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  * Adds export_for_template behaviour to an mform element in a consistent and predictable way.
  19  *
  20  * @package   core_form
  21  * @copyright 2016 Damyon Wiese
  22  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24 defined('MOODLE_INTERNAL') || die();
  25
  26 // Some form elements are used before $CFG is created - do not rely on it here.
  27 require_once(__DIR__ . '/../outputcomponents.php');
  28
  29 /**
  30  * templatable_form_element trait.
  31  *
  32  * @package   core_form
  33  * @copyright 2016 Damyon Wiese
  34  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  35  */
  36 trait templatable_form_element {
  37
  38     /**
  39      * Function to export the renderer data in a format that is suitable for a
  40      * mustache template. This means:
  41      * 1. No complex types - only stdClass, array, int, string, float, bool
  42      * 2. Any additional info that is required for the template is pre-calculated (e.g. capability checks).
  43      *
  44      * This trait can be used as-is for simple form elements - or imported with a different name
  45      * so it can be extended with additional context variables before being returned.
  46      *
  47      * @param renderer_base $output Used to do a final render of any components that need to be rendered for export.
  48      * @return stdClass|array
  49      */
  50     public function export_for_template(renderer_base $output) {
  51         $context = [];
  52
  53         // Not all elements have all of these attributes - but they are common enough to be valid for a few.
  54         $standardattributes = ['id', 'name', 'label', 'multiple', 'checked', 'error', 'size', 'value', 'type'];
  55         $standardproperties = ['helpbutton', 'hiddenLabel'];
  56
  57         // Standard attributes.
  58         foreach ($standardattributes as $attrname) {
  59             $value = $this->getAttribute($attrname);
  60             $context[$attrname] = $value;
  61         }
  62
  63         // Standard class properties.
  64         foreach ($standardproperties as $propname) {
  65             $classpropname = '_' . $propname;
  66             $context[strtolower($propname)] = isset($this->$classpropname) ? $this->$classpropname : false;
  67         }
  68         $extraclasses = $this->getAttribute('class');
  69
  70         // Special wierd named property.
  71         $context['frozen'] = !empty($this->_flagFrozen);
  72         $context['hardfrozen'] = !empty($this->_flagFrozen) && empty($this->_persistantFreeze);
  73
  74         // Other attributes.
  75         $otherattributes = [];
  76         foreach ($this->getAttributes() as $attr => $value) {
  77             if (!in_array($attr, $standardattributes) && $attr != 'class' && !is_object($value)) {
  78                 $otherattributes[] = $attr . '="' . s($value) . '"';
  79             }
  80         }
  81         $context['extraclasses'] = $extraclasses;
  82         $context['type'] = $this->getType();
  83         $context['attributes'] = implode(' ', $otherattributes);
  84         $context['emptylabel'] = ($this->getLabel() === '');
  85
  86         // Elements with multiple values need array syntax.
  87         if ($this->getAttribute('multiple')) {
  88             $context['name'] = $context['name'] . '[]';
  89         }
  90
  91         return $context;
  92     }
  93 }