class Checkboxes

Same name in other branches
  1. 9 core/lib/Drupal/Core/Render/Element/Checkboxes.php \Drupal\Core\Render\Element\Checkboxes
  2. 8.9.x core/lib/Drupal/Core/Render/Element/Checkboxes.php \Drupal\Core\Render\Element\Checkboxes
  3. 10 core/lib/Drupal/Core/Render/Element/Checkboxes.php \Drupal\Core\Render\Element\Checkboxes

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:


$form['favorites']['colors'] = [
  '#type' => 'checkboxes',
  '#options' => ['blue' => $this->t('Blue'), 'red' => $this->t('Red')],
  '#title' => $this->t('Which colors do you like?'),
  ...
];

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

$form['favorites']['colors']['blue']['#description'] = $this->t('The color of the sky.');

Hierarchy

Expanded class hierarchy of Checkboxes

See also

\Drupal\Core\Render\Element\Radios

\Drupal\Core\Render\Element\Checkbox

3 files declare their use of Checkboxes
FilterPluginBase.php in core/modules/views/src/Plugin/views/filter/FilterPluginBase.php
ViewsExposedForm.php in core/modules/views/src/Form/ViewsExposedForm.php
views_ui.theme.inc in core/modules/views_ui/views_ui.theme.inc
Preprocessors and theme functions for the Views UI.
18 string references to 'Checkboxes'
Checkboxes::getInfo in core/lib/Drupal/Core/Render/Element/Checkboxes.php
Returns the element properties for this element.
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.
ElementTest::testOptions in core/modules/system/tests/src/Functional/Form/ElementTest.php
Tests expansion of #options for #type checkboxes and radios.
ElementTest::testWrapperIds in core/modules/system/tests/src/Functional/Form/ElementTest.php
Tests wrapper ids for checkboxes and radios.

... See full list

File

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

Namespace

Drupal\Core\Render\Element
View source
class Checkboxes extends FormElementBase {
    use CompositeFormElementTrait;
    
    /**
     * {@inheritdoc}
     */
    public function getInfo() {
        $class = static::class;
        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;
                // Only enabled checkboxes receive their values from the form
                // submission, the disabled checkboxes use their default value.
                $default_value = NULL;
                if (isset($value[$key]) || !empty($element[$key]['#disabled']) && in_array($key, $element['#default_value'], TRUE)) {
                    $default_value = $key;
                }
                $element += [
                    $key => [],
                ];
                $element[$key] += [
                    '#type' => 'checkbox',
                    '#title' => $choice,
                    '#return_value' => $key,
                    '#default_value' => $default_value,
                    '#attributes' => $element['#attributes'],
                    '#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]);
                }
            }
            // Because the disabled checkboxes don't receive their input from the
            // form submission, we use their default value.
            if (!empty($element['#default_value'])) {
                foreach ($element['#default_value'] as $key) {
                    if (!empty($element[$key]['#disabled'])) {
                        $input[$key] = $key;
                    }
                }
            }
            return array_combine($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));
    }

}

Members

Title Sort descending Modifiers Object type Summary Overriden Title Overrides
Checkboxes::detectEmptyCheckboxes public static function Determines if all checkboxes in a set are unchecked.
Checkboxes::getCheckedCheckboxes public static function Determines which checkboxes were checked when a form is submitted.
Checkboxes::getInfo public function Returns the element properties for this element. Overrides ElementInterface::getInfo
Checkboxes::processCheckboxes public static function Processes a checkboxes form element.
Checkboxes::valueCallback public static function Determines how user input is mapped to an element's #value property. Overrides FormElementBase::valueCallback
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
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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