Version 1

[yaffs-website] / web / core / lib / Drupal / Core / Render / Element / Checkboxes.php

diff --git a/web/core/lib/Drupal/Core/Render/Element/Checkboxes.php b/web/core/lib/Drupal/Core/Render/Element/Checkboxes.php
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+++ b/web/core/lib/Drupal/Core/Render/Element/Checkboxes.php
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+<?php
+
+namespace Drupal\Core\Render\Element;
+
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Provides a form element for a set of checkboxes.
+ *
+ * Properties:
+ * - #options: An associative array whose keys are the values returned for each
+ *   checkbox, and whose values are the labels next to each checkbox. The
+ *   #options array cannot have a 0 key, as it would not be possible to discern
+ *   checked and unchecked states.
+ *
+ * Usage example:
+ * @code
+ * $form['high_school']['tests_taken'] = array(
+ *   '#type' => 'checkboxes',
+ *   '#options' => array('SAT' => $this->t('SAT'), 'ACT' => $this->t('ACT')),
+ *   '#title' => $this->t('What standardized tests did you take?'),
+ *   ...
+ * );
+ * @endcode
+ *
+ * @see \Drupal\Core\Render\Element\Radios
+ * @see \Drupal\Core\Render\Element\Checkbox
+ *
+ * @FormElement("checkboxes")
+ */
+class Checkboxes extends FormElement {
+
+  use CompositeFormElementTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getInfo() {
+    $class = get_class($this);
+    return [
+      '#input' => TRUE,
+      '#process' => [
+        [$class, 'processCheckboxes'],
+      ],
+      '#pre_render' => [
+        [$class, 'preRenderCompositeFormElement'],
+      ],
+      '#theme_wrappers' => ['checkboxes'],
+    ];
+  }
+
+  /**
+   * Processes a checkboxes form element.
+   */
+  public static function processCheckboxes(&$element, FormStateInterface $form_state, &$complete_form) {
+    $value = is_array($element['#value']) ? $element['#value'] : [];
+    $element['#tree'] = TRUE;
+    if (count($element['#options']) > 0) {
+      if (!isset($element['#default_value']) || $element['#default_value'] == 0) {
+        $element['#default_value'] = [];
+      }
+      $weight = 0;
+      foreach ($element['#options'] as $key => $choice) {
+        // Integer 0 is not a valid #return_value, so use '0' instead.
+        // @see \Drupal\Core\Render\Element\Checkbox::valueCallback().
+        // @todo For Drupal 8, cast all integer keys to strings for consistency
+        //   with \Drupal\Core\Render\Element\Radios::processRadios().
+        if ($key === 0) {
+          $key = '0';
+        }
+        // Maintain order of options as defined in #options, in case the element
+        // defines custom option sub-elements, but does not define all option
+        // sub-elements.
+        $weight += 0.001;
+
+        $element += [$key => []];
+        $element[$key] += [
+          '#type' => 'checkbox',
+          '#title' => $choice,
+          '#return_value' => $key,
+          '#default_value' => isset($value[$key]) ? $key : NULL,
+          '#attributes' => $element['#attributes'],
+          '#ajax' => isset($element['#ajax']) ? $element['#ajax'] : NULL,
+          // Errors should only be shown on the parent checkboxes element.
+          '#error_no_message' => TRUE,
+          '#weight' => $weight,
+        ];
+      }
+    }
+    return $element;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function valueCallback(&$element, $input, FormStateInterface $form_state) {
+    if ($input === FALSE) {
+      $value = [];
+      $element += ['#default_value' => []];
+      foreach ($element['#default_value'] as $key) {
+        $value[$key] = $key;
+      }
+      return $value;
+    }
+    elseif (is_array($input)) {
+      // Programmatic form submissions use NULL to indicate that a checkbox
+      // should be unchecked. We therefore remove all NULL elements from the
+      // array before constructing the return value, to simulate the behavior
+      // of web browsers (which do not send unchecked checkboxes to the server
+      // at all). This will not affect non-programmatic form submissions, since
+      // all values in \Drupal::request()->request are strings.
+      // @see \Drupal\Core\Form\FormBuilderInterface::submitForm()
+      foreach ($input as $key => $value) {
+        if (!isset($value)) {
+          unset($input[$key]);
+        }
+      }
+      return array_combine($input, $input);
+    }
+    else {
+      return [];
+    }
+  }
+
+  /**
+   * Determines which checkboxes were checked when a form is submitted.
+   *
+   * @param array $input
+   *   An array returned by the FormAPI for a set of checkboxes.
+   *
+   * @return array
+   *   An array of keys that were checked.
+   */
+  public static function getCheckedCheckboxes(array $input) {
+    // Browsers do not include unchecked options in a form submission. The
+    // FormAPI tries to normalize this to keep checkboxes consistent with other
+    // form elements. Checkboxes show up as an array in the form of option_id =>
+    // option_id|0, where integer 0 is an unchecked option.
+    //
+    // @see \Drupal\Core\Render\Element\Checkboxes::valueCallback()
+    // @see https://www.w3.org/TR/html401/interact/forms.html#checkbox
+    $checked = array_filter($input, function($value) {
+      return $value !== 0;
+    });
+    return array_keys($checked);
+  }
+
+  /**
+   * Determines if all checkboxes in a set are unchecked.
+   *
+   * @param array $input
+   *   An array returned by the FormAPI for a set of checkboxes.
+   *
+   * @return bool
+   *   TRUE if all options are unchecked. FALSE otherwise.
+   */
+  public static function detectEmptyCheckboxes(array $input) {
+    return empty(static::getCheckedCheckboxes($input));
+  }
+
+}