class Radios

Same name and namespace in other branches
  1. 9 core/lib/Drupal/Core/Render/Element/Radios.php \Drupal\Core\Render\Element\Radios
  2. 8.9.x core/lib/Drupal/Core/Render/Element/Radios.php \Drupal\Core\Render\Element\Radios
  3. 11.x core/lib/Drupal/Core/Render/Element/Radios.php \Drupal\Core\Render\Element\Radios

Provides a form element for a set of radio buttons.

Properties:

  • #options: An associative array, where the keys are the returned values for each radio button, and the values are the labels next to each radio button.

Usage example:

$form['settings']['active'] = [
  '#type' => 'radios',
  '#title' => $this->t('Poll status'),
  '#default_value' => 1,
  '#options' => [
    0 => $this->t('Closed'),
    1 => $this->t('Active'),
  ],
];

Element properties may be set on single option items as follows.

$form['settings']['active'][0]['#description'] = $this->t('Description for the Closed option.');

Hierarchy

Expanded class hierarchy of Radios

See also

\Drupal\Core\Render\Element\Checkboxes

\Drupal\Core\Render\Element\Radio

\Drupal\Core\Render\Element\Select

1 file declares its use of Radios
views_ui.theme.inc in core/modules/views_ui/views_ui.theme.inc
Preprocessors and theme functions for the Views UI.
21 string references to 'Radios'
BlockForm::buildVisibilityInterface in core/modules/block/src/BlockForm.php
Helper function for building the visibility UI form.
BooleanOperator::valueForm in core/modules/views/src/Plugin/views/filter/BooleanOperator.php
Options form subform for setting options.
ckeditor5_form_filter_format_form_alter in core/modules/ckeditor5/ckeditor5.module
Implements hook_form_FORM_ID_alter().
claro_preprocess_fieldset in core/themes/claro/claro.theme
Implements template_preprocess_HOOK() for fieldset.
ContentTranslationHandler::addTranslatabilityClue in core/modules/content_translation/src/ContentTranslationHandler.php
Adds a clue about the form element translatability.

... See full list

File

core/lib/Drupal/Core/Render/Element/Radios.php, line 36

Namespace

Drupal\Core\Render\Element
View source
class Radios extends FormElementBase {
  use CompositeFormElementTrait;
  
  /**
   * {@inheritdoc}
   */
  public function getInfo() {
    $class = static::class;
    return [
      '#input' => TRUE,
      '#process' => [
        [
          $class,
          'processRadios',
        ],
      ],
      '#theme_wrappers' => [
        'radios',
      ],
      '#pre_render' => [
        [
          $class,
          'preRenderCompositeFormElement',
        ],
      ],
    ];
  }
  
  /**
   * Expands a radios element into individual radio elements.
   */
  public static function processRadios(&$element, FormStateInterface $form_state, &$complete_form) {
    if (count($element['#options']) > 0) {
      $weight = 0;
      foreach ($element['#options'] as $key => $choice) {
        // 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 => [],
        ];
        // Generate the parents as the autogenerator does, so we will have a
        // unique id for each radio button.
        $parents_for_id = array_merge($element['#parents'], [
          $key,
        ]);
        $element[$key] += [
          '#type' => 'radio',
          '#title' => $choice,
          // The key is sanitized in Drupal\Core\Template\Attribute during output
          // from the theme function.
'#return_value' => $key,
          // Use default or FALSE. A value of FALSE means that the radio button is
          // not 'checked'.
'#default_value' => $element['#default_value'] ?? FALSE,
          '#attributes' => $element['#attributes'],
          '#parents' => $element['#parents'],
          '#id' => HtmlUtility::getUniqueId('edit-' . implode('-', $parents_for_id)),
          '#ajax' => $element['#ajax'] ?? NULL,
          // Errors should only be shown on the parent radios element.
'#error_no_message' => TRUE,
          '#weight' => $weight,
        ];
      }
    }
    return $element;
  }
  
  /**
   * {@inheritdoc}
   */
  public static function valueCallback(&$element, $input, FormStateInterface $form_state) {
    if ($input !== FALSE) {
      // When there's user input (including NULL), return it as the value.
      // However, if NULL is submitted, FormBuilder::handleInputElement() will
      // apply the default value, and we want that validated against #options
      // unless it's empty. (An empty #default_value, such as NULL or FALSE, can
      // be used to indicate that no radio button is selected by default.)
      if (!isset($input) && !empty($element['#default_value'])) {
        $element['#needs_validation'] = TRUE;
      }
      return $input;
    }
    else {
      // For default value handling, simply return #default_value. Additionally,
      // for a NULL default value, set #has_garbage_value to prevent
      // FormBuilder::handleInputElement() converting the NULL to an empty
      // string, so that code can distinguish between nothing selected and the
      // selection of a radio button whose value is an empty string.
      $value = $element['#default_value'] ?? NULL;
      if (!isset($value)) {
        $element['#has_garbage_value'] = TRUE;
      }
      return $value;
    }
  }

}

Members

Title Sort descending Modifiers Object type Summary Overriden Title Overrides
CompositeFormElementTrait::preRenderCompositeFormElement public static function Adds form element theming to an element if its title or description is set.
FormElementBase::processAutocomplete public static function Adds autocomplete functionality to elements. 1
FormElementBase::processPattern public static function #process callback for #pattern form element property. 1
FormElementBase::validatePattern public static function #element_validate callback for #pattern form element property. 1
PluginInspectionInterface::getPluginDefinition public function Gets the definition of the plugin implementation. 6
PluginInspectionInterface::getPluginId public function Gets the plugin ID of the plugin instance. 2
Radios::getInfo public function Returns the element properties for this element. Overrides ElementInterface::getInfo
Radios::processRadios public static function Expands a radios element into individual radio elements.
Radios::valueCallback public static function Determines how user input is mapped to an element's #value property. Overrides FormElementBase::valueCallback
RenderElementBase::preRenderAjaxForm public static function Adds Ajax information about an element to communicate with JavaScript. 2
RenderElementBase::preRenderGroup public static function Adds members of this group as actual elements for rendering. 2
RenderElementBase::processAjaxForm public static function Form element processing handler for the #ajax form property. 3
RenderElementBase::processGroup public static function Arranges elements into groups. 2
RenderElementBase::setAttributes public static function Sets a form element's class attribute. Overrides ElementInterface::setAttributes 2

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