class StatusMessages

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

Provides a messages element.

Used to display results of \Drupal::messenger()->addMessage() calls.

Usage example:

$build['status_messages'] = [
    '#type' => 'status_messages',
];

Hierarchy

Expanded class hierarchy of StatusMessages

File

core/lib/Drupal/Core/Render/Element/StatusMessages.php, line 19

Namespace

Drupal\Core\Render\Element
View source
class StatusMessages extends RenderElementBase {
    
    /**
     * {@inheritdoc}
     *
     * Generate the placeholder in a #pre_render callback, because the hash salt
     * needs to be accessed, which may not yet be available when this is called.
     */
    public function getInfo() {
        return [
            // May have a value of 'status' or 'error' when only displaying messages
            // of that specific type.
'#display' => NULL,
            '#pre_render' => [
                static::class . '::generatePlaceholder',
            ],
            '#include_fallback' => FALSE,
        ];
    }
    
    /**
     * #pre_render callback to generate a placeholder.
     *
     * @param array $element
     *   A renderable array.
     *
     * @return array
     *   The updated renderable array containing the placeholder.
     */
    public static function generatePlaceholder(array $element) {
        $build = [
            '#lazy_builder' => [
                static::class . '::renderMessages',
                [
                    $element['#display'],
                ],
            ],
            '#create_placeholder' => TRUE,
        ];
        // Directly create a placeholder as we need this to be placeholdered
        // regardless if this is a POST or GET request.
        // @todo remove this when https://www.drupal.org/node/2367555 lands.
        $build = \Drupal::service('render_placeholder_generator')->createPlaceholder($build);
        if ($element['#include_fallback']) {
            return [
                'fallback' => [
                    '#markup' => '<div data-drupal-messages-fallback class="hidden"></div>',
                ],
                'messages' => $build,
            ];
        }
        return $build;
    }
    
    /**
     * #lazy_builder callback; replaces placeholder with messages.
     *
     * @param string|null $type
     *   Limit the messages returned by type. Defaults to NULL, meaning all types.
     *   Passed on to \Drupal\Core\Messenger\Messenger::deleteByType(). These
     *   values are supported:
     *   - NULL
     *   - 'status'
     *   - 'warning'
     *   - 'error'
     *
     * @return array
     *   A renderable array containing the messages.
     *
     * @see \Drupal\Core\Messenger\Messenger::deleteByType()
     */
    public static function renderMessages($type = NULL) {
        $render = [];
        if (isset($type)) {
            $messages = [
                $type => \Drupal::messenger()->deleteByType($type),
            ];
        }
        else {
            $messages = \Drupal::messenger()->deleteAll();
        }
        if ($messages) {
            // Render the messages.
            $render = [
                '#theme' => 'status_messages',
                '#message_list' => $messages,
                '#status_headings' => [
                    'status' => t('Status message'),
                    'error' => t('Error message'),
                    'warning' => t('Warning message'),
                ],
            ];
        }
        return $render;
    }

}

Members

Title Sort descending Modifiers Object type Summary Overriden Title Overrides
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&#039;s class attribute. Overrides ElementInterface::setAttributes 2
StatusMessages::generatePlaceholder public static function #pre_render callback to generate a placeholder.
StatusMessages::getInfo public function Generate the placeholder in a #pre_render callback, because the hash salt
needs to be accessed, which may not yet be available when this is called.
Overrides ElementInterface::getInfo
StatusMessages::renderMessages public static function #lazy_builder callback; replaces placeholder with messages.

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