RulesComponentAddForm.php

<?php

namespace Drupal\rules\Form;

use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Routing\RouteMatchInterface;

/**
 * Provides a form to add a component.
 */
class RulesComponentAddForm extends RulesComponentFormBase {
    
    /**
     * {@inheritdoc}
     */
    public function getEntityFromRouteMatch(RouteMatchInterface $route_match, $entity_type_id) {
        // Overridden to customize creation of new entities.
        if ($route_match->getRawParameter($entity_type_id) !== NULL) {
            $entity = $route_match->getParameter($entity_type_id);
        }
        else {
            $values = [];
            // @todo Create the right expression depending on the route.
            $entity = $this->entityTypeManager
                ->getStorage($entity_type_id)
                ->create($values);
            $entity->setExpression($this->expressionManager
                ->createRule());
        }
        return $entity;
    }
    
    /**
     * {@inheritdoc}
     */
    protected function actions(array $form, FormStateInterface $form_state) {
        $actions = parent::actions($form, $form_state);
        $actions['submit']['#value'] = $this->t('Save');
        return $actions;
    }
    
    /**
     * {@inheritdoc}
     */
    public function save(array $form, FormStateInterface $form_state) {
        parent::save($form, $form_state);
        $this->messenger()
            ->addMessage($this->t('Component %label has been created.', [
            '%label' => $this->entity
                ->label(),
        ]));
        $form_state->setRedirect('entity.rules_component.edit_form', [
            'rules_component' => $this->entity
                ->id(),
        ]);
    }

}