function HtmlRenderer::prepare

Same name in other branches
  1. 9 core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php \Drupal\Core\Render\MainContent\HtmlRenderer::prepare()
  2. 8.9.x core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php \Drupal\Core\Render\MainContent\HtmlRenderer::prepare()
  3. 11.x core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php \Drupal\Core\Render\MainContent\HtmlRenderer::prepare()

Prepares the HTML body: wraps the main content in #type 'page'.

Parameters

array $main_content: The render array representing the main content.

\Symfony\Component\HttpFoundation\Request $request: The request object, for context.

\Drupal\Core\Routing\RouteMatchInterface $route_match: The route match, for context.

Return value

array An array with two values: 0. A #type 'page' render array. 1. The page title.

Throws

\LogicException If the selected display variant does not implement PageVariantInterface.

1 call to HtmlRenderer::prepare()
HtmlRenderer::renderResponse in core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
The entire HTML: takes a #type 'page' and wraps it in a #type 'html'.

File

core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php, line 200

Class

HtmlRenderer
Default main content renderer for HTML requests.

Namespace

Drupal\Core\Render\MainContent

Code

protected function prepare(array $main_content, Request $request, RouteMatchInterface $route_match) {
    // Determine the title: use the title provided by the main content if any,
    // otherwise get it from the routing information.
    $get_title = function (array $main_content) use ($request, $route_match) {
        return $main_content['#title'] ?? $this->titleResolver
            ->getTitle($request, $route_match->getRouteObject());
    };
    // If the _controller result already is #type => page,
    // we have no work to do: The "main content" already is an entire "page"
    // (see html.html.twig).
    if (isset($main_content['#type']) && $main_content['#type'] === 'page') {
        $page = $main_content;
        $title = $get_title($page);
    }
    else {
        // Select the page display variant to be used to render this main content,
        // default to the built-in "simple page".
        $event = new PageDisplayVariantSelectionEvent('simple_page', $route_match);
        $this->eventDispatcher
            ->dispatch($event, RenderEvents::SELECT_PAGE_DISPLAY_VARIANT);
        $variant_id = $event->getPluginId();
        $variant_configuration = $event->getPluginConfiguration();
        // We must render the main content now already, because it might provide a
        // title. We set its $is_root_call parameter to FALSE, to ensure
        // placeholders are not yet replaced. This is essentially "pre-rendering"
        // the main content, the "full rendering" will happen in
        // ::renderResponse().
        // @todo Remove this once https://www.drupal.org/node/2359901 lands.
        if (!empty($main_content)) {
            $this->renderer
                ->executeInRenderContext(new RenderContext(), function () use (&$main_content) {
                if (isset($main_content['#cache']['keys'])) {
                    // Retain #title, otherwise, dynamically generated titles would be
                    // missing for controllers whose entire returned render array is
                    // render cached.
                    $main_content['#cache_properties'][] = '#title';
                }
                return $this->renderer
                    ->render($main_content, FALSE);
            });
            $main_content = $this->renderCache
                ->getCacheableRenderArray($main_content) + [
                '#title' => $main_content['#title'] ?? NULL,
            ];
        }
        $title = $get_title($main_content);
        // Instantiate the page display, and give it the main content.
        $page_display = $this->displayVariantManager
            ->createInstance($variant_id, $variant_configuration);
        if (!$page_display instanceof PageVariantInterface) {
            throw new \LogicException('Cannot render the main content for this page because the provided display variant does not implement PageVariantInterface.');
        }
        $page_display->setMainContent($main_content)
            ->setTitle($title)
            ->addCacheableDependency($event);
        // Some display variants need to be passed an array of contexts with
        // values because they can't get all their contexts globally. For example,
        // in Page Manager, you can create a Page which has a specific static
        // context (e.g. a context that refers to the Node with nid 6), if any
        // such contexts were added to the $event, pass them to the $page_display.
        if ($page_display instanceof ContextAwareVariantInterface) {
            $page_display->setContexts($event->getContexts());
        }
        // Generate a #type => page render array using the page display variant,
        // the page display will build the content for the various page regions.
        $page = [
            '#type' => 'page',
        ];
        $page += $page_display->build();
    }
    // $page is now fully built. Find all non-empty page regions, and add a
    // theme wrapper function that allows them to be consistently themed.
    $regions = $this->themeManager
        ->getActiveTheme()
        ->getRegions();
    foreach ($regions as $region) {
        if (!empty($page[$region])) {
            $page[$region]['#theme_wrappers'][] = 'region';
            $page[$region]['#region'] = $region;
        }
    }
    // Allow hooks to add attachments to $page['#attached'].
    $this->renderer
        ->executeInRenderContext(new RenderContext(), function () use (&$page) {
        $this->invokePageAttachmentHooks($page);
    });
    return [
        $page,
        $title,
    ];
}

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