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. 9 core/lib/Drupal/Core/Render/Element/Button.php \Drupal\Core\Render\Element\Button
  4. 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:

  • If #submit_button is TRUE (default), the form will be submitted to Drupal, where it is validated and rebuilt. The submit handler is not invoked.
  • If #submit_button is FALSE, the button will act as a regular HTML button (with the 'type' attribute set to 'button') and will not trigger a form submission. This allows developers to define custom client-side behavior using JavaScript or other mechanisms.

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.
  • #submit_button: This has a default value of TRUE. If set to FALSE, the 'type' attribute is set to 'button.'

Usage Example:

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

Attributes

#[FormElement('button')]

Hierarchy

Expanded class hierarchy of Button

See also

\Drupal\Core\Render\Element\Submit

57 string references to 'Button'
AjaxTestForm::buildForm in core/modules/system/tests/modules/ajax_test/src/Form/AjaxTestForm.php
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
CKEditor5Test::testListPlugin in core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditor5Test.php
Tests list plugin.

... See full list

10 #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
Form constructor.
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

View on git.drupalcode.org

core/lib/Drupal/Core/Render/Element/Button.php, line 39

Namespace

Drupal\Core\Render\Element
View source 
class Button extends FormElementBase {
  
  /**
   * {@inheritdoc}
   */
  public function getInfo() {
    return [
      '#input' => TRUE,
      '#name' => 'op',
      '#is_button' => TRUE,
      '#submit_button' => TRUE,
      '#executes_submit_callback' => FALSE,
      '#limit_validation_errors' => FALSE,
      '#process' => [
        [
          static::class,
          'processButton',
        ],
        [
          static::class,
          'processAjaxForm',
        ],
      ],
      '#pre_render' => [
        [
          static::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, #submit_button,
   *   #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) {
    if ($element['#submit_button']) {
      $element['#attributes']['type'] = 'submit';
    }
    else {
      $element['#attributes']['type'] = 'button';
    }
    Element::setAttributes($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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