class HtmlFormController

HtmlEntityFormController.php in drupal/core/lib/Drupal/Core/Entity/HtmlEntityFormController.php

Contains \Drupal\Core\Entity\HtmlEntityFormController.

class HtmlFormController implements ContainerAwareInterface {

  /**
   * The injection container for this object.
   *
   * @var \Symfony\Component\DependencyInjection\ContainerInterface
   */
  protected $container;

  /**
   * Injects the service container used by this object.
   *
   * @param \Symfony\Component\DependencyInjection\ContainerInterface $container
   *   The service container this object should use.
   */
  public function setContainer(ContainerInterface $container = NULL) {
    $this->container = $container;
  }

  /**
   * Controller method for generic HTML form pages.
   *
   * @param \Symfony\Component\HttpFoundation\Request $request
   *   The request object.
   * @param callable $_form
   *   The name of the form class for this request.
   *
   * @return \Symfony\Component\HttpFoundation\Response
   *   A response object.
   */
  public function content(Request $request, $_form) {
    $form_object = $this
      ->getFormObject($request, $_form);

    // Using reflection, find all of the parameters needed by the form in the
    // request attributes, skipping $form and $form_state.
    // At the form and form_state to trick the getArguments method of the
    // controller resolver.
    $form_state = array();
    $request->attributes
      ->set('form', array());
    $request->attributes
      ->set('form_state', $form_state);
    $args = $this->container
      ->get('controller_resolver')
      ->getArguments($request, array(
      $form_object,
      'buildForm',
    ));
    unset($args[0], $args[1]);
    $request->attributes
      ->remove('form');
    $request->attributes
      ->remove('form_state');
    $form_state['build_info']['args'] = $args;
    $form_id = _drupal_form_id($form_object, $form_state);
    return drupal_build_form($form_id, $form_state);
  }

  /**
   * Returns the object used to build the form.
   *
   * @param \Symfony\Component\HttpFoundation\Request $request
   *   The request using this form.
   * @param string $form_arg
   *   Either a class name or a service ID.
   *
   * @return \Drupal\Core\Form\FormInterface
   *   The form object to use.
   */
  protected function getFormObject(Request $request, $form_arg) {

    // If this is a class, instantiate it.
    if (class_exists($form_arg)) {
      if (in_array('Drupal\\Core\\Controller\\ControllerInterface', class_implements($form_arg))) {
        return $form_arg::create($this->container);
      }
      return new $form_arg();
    }

    // Otherwise, it is a service.
    return $this->container
      ->get($form_arg);
  }

}