class Button

Same name and namespace in other branches
  1. 11.x core/lib/Drupal/Core/Render/Element/Button.php \Drupal\Core\Render\Element\Button
  2. 10 core/lib/Drupal/Core/Render/Element/Button.php \Drupal\Core\Render\Element\Button
  3. 8.9.x 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'] = array(
  '#type' => 'button',
  '#value' => $this->t('Preview'),
);

Plugin annotation

@FormElement("button");

Hierarchy

Expanded class hierarchy of Button

See also

\Drupal\Core\Render\Element\Submit

43 string references to 'Button'
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.
ckeditor.schema.yml in core/modules/ckeditor/config/schema/ckeditor.schema.yml
core/modules/ckeditor/config/schema/ckeditor.schema.yml
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

9 #type uses of Button
AjaxTestImageEffect::buildConfigurationForm in core/modules/image/tests/modules/image_module_test/src/Plugin/ImageEffect/AjaxTestImageEffect.php
ContentModerationConfigureEntityTypesForm::buildForm in core/modules/content_moderation/src/Form/ContentModerationConfigureEntityTypesForm.php
FormElementsRenderTest::testDrupalRenderFormElements in core/modules/system/tests/src/Kernel/Common/FormElementsRenderTest.php
Tests rendering form elements without using doBuildForm().
FormTestButtonClassForm::buildForm in core/modules/system/tests/modules/form_test/src/Form/FormTestButtonClassForm.php
FormTestDisabledElementsForm::buildForm in core/modules/system/tests/modules/form_test/src/Form/FormTestDisabledElementsForm.php

... See full list

File

core/lib/Drupal/Core/Render/Element/Button.php, line 33

Namespace

Drupal\Core\Render\Element
View on git.drupalcode.org
View source 
class Button extends FormElement {
  
  /**
   * {@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;
  }

}

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