class Button

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

Provides an action button form element.

When the button is pressed, the form will be submitted to Drupal, where it is validated and rebuilt. The submit handler is not invoked.

Properties:

  • #limit_validation_errors: An array of form element keys that will block form submission when validation for these elements or any child elements fails. Specify an empty array to suppress all form validation errors.
  • #value: The text to be shown on the button.

Usage Example:

$form['actions']['preview'] = [
    '#type' => 'button',
    '#value' => $this->t('Preview'),
];

Hierarchy

Expanded class hierarchy of Button

See also

\Drupal\Core\Render\Element\Submit

55 string references to 'Button'
AjaxTestForm::buildForm in core/modules/system/tests/modules/ajax_test/src/Form/AjaxTestForm.php
Form constructor.
BlockListBuilder::buildBlocksForm in core/modules/block/src/BlockListBuilder.php
Builds the main "Blocks" portion of the form.
Button::preRenderButton in core/lib/Drupal/Core/Render/Element/Button.php
Prepares a #type 'button' render element for input.html.twig.
ckeditor5.schema.yml in core/modules/ckeditor5/config/schema/ckeditor5.schema.yml
core/modules/ckeditor5/config/schema/ckeditor5.schema.yml
claro_views_ui_display_top_alter in core/themes/claro/claro.theme
Implements hook_views_ui_display_top_alter().

... See full list

File

core/lib/Drupal/Core/Render/Element/Button.php, line 32

Namespace

Drupal\Core\Render\Element
View source 
class Button extends FormElementBase {
    
    /**
     * {@inheritdoc}
     */
    public function getInfo() {
        $class = static::class;
        return [
            '#input' => TRUE,
            '#name' => 'op',
            '#is_button' => TRUE,
            '#executes_submit_callback' => FALSE,
            '#limit_validation_errors' => FALSE,
            '#process' => [
                [
                    $class,
                    'processButton',
                ],
                [
                    $class,
                    'processAjaxForm',
                ],
            ],
            '#pre_render' => [
                [
                    $class,
                    'preRenderButton',
                ],
            ],
            '#theme_wrappers' => [
                'input__submit',
            ],
        ];
    }
    
    /**
     * Processes a form button element.
     */
    public static function processButton(&$element, FormStateInterface $form_state, &$complete_form) {
        // If this is a button intentionally allowing incomplete form submission
        // (e.g., a "Previous" or "Add another item" button), then also skip
        // client-side validation.
        if (isset($element['#limit_validation_errors']) && $element['#limit_validation_errors'] !== FALSE) {
            $element['#attributes']['formnovalidate'] = 'formnovalidate';
        }
        return $element;
    }
    
    /**
     * Prepares a #type 'button' render element for input.html.twig.
     *
     * @param array $element
     *   An associative array containing the properties of the element.
     *   Properties used: #attributes, #button_type, #name, #value. The
     *   #button_type property accepts any value, though core themes have CSS that
     *   styles the following button_types appropriately: 'primary', 'danger'.
     *
     * @return array
     *   The $element with prepared variables ready for input.html.twig.
     */
    public static function preRenderButton($element) {
        $element['#attributes']['type'] = 'submit';
        Element::setAttributes($element, [
            'id',
            'name',
            'value',
        ]);
        $element['#attributes']['class'][] = 'button';
        if (!empty($element['#button_type'])) {
            $element['#attributes']['class'][] = 'button--' . $element['#button_type'];
        }
        $element['#attributes']['class'][] = 'js-form-submit';
        $element['#attributes']['class'][] = 'form-submit';
        if (!empty($element['#attributes']['disabled'])) {
            $element['#attributes']['class'][] = 'is-disabled';
        }
        return $element;
    }

}

Members

Title Modifiers Object type Summary Overriden Title Overrides
Button::getInfo public function Returns the element properties for this element. Overrides ElementInterface::getInfo 1
Button::preRenderButton public static function Prepares a #type 'button' render element for input.html.twig. 1
Button::processButton public static function Processes a form button element.
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
FormElementBase::valueCallback public static function Determines how user input is mapped to an element's #value property. Overrides FormElementInterface::valueCallback 17
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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