function ViewsBlock::build

Overrides BlockPluginInterface::build

File

core/modules/views/src/Plugin/Block/ViewsBlock.php, line 26

Class

ViewsBlock

Provides a generic Views block.

Namespace

Code

public function build() {
    $this->view->display_handler
        ->preBlockBuild($this);
    $args = [];
    foreach ($this->view->display_handler
        ->getHandlers('argument') as $argument_name => $argument) {
        // Initialize the argument value. Work around a limitation in
        // \Drupal\views\ViewExecutable::_buildArguments() that skips processing
        // later arguments if an argument with default action "ignore" and no
        // argument is provided.
        $args[$argument_name] = $argument->options['default_action'] == 'ignore' ? 'all' : NULL;
        if (!empty($this->context[$argument_name])) {
            if ($value = $this->context[$argument_name]
                ->getContextValue()) {
                // Context values are often entities, but views arguments expect to
                // receive just the entity ID, convert it.
                if ($value instanceof EntityInterface) {
                    $value = $value->id();
                }
                $args[$argument_name] = $value;
            }
        }
    }
    // We ask ViewExecutable::buildRenderable() to avoid creating a render cache
    // entry for the view output by passing FALSE, because we're going to cache
    // the whole block instead.
    if ($output = $this->view
        ->buildRenderable($this->displayID, array_values($args), FALSE)) {
        // Before returning the block output, convert it to a renderable array
        // with contextual links.
        $this->addContextualLinks($output);
        // Block module expects to get a final render array, without another
        // top-level #pre_render callback. So, here we make sure that Views'
        // #pre_render callback has already been applied.
        $output = View::preRenderViewElement($output);
        // Inject the overridden block title into the view.
        if (!empty($this->configuration['views_label'])) {
            $this->view
                ->setTitle($this->configuration['views_label']);
        }
        // Override the block title to match the view title.
        if ($this->view
            ->getTitle()) {
            $output['#title'] = [
                '#markup' => $this->view
                    ->getTitle(),
                '#allowed_tags' => Xss::getHtmlTagList(),
            ];
        }
        // When view_build is empty, the actual render array output for this View
        // is going to be empty. In that case, return just #cache, so that the
        // render system knows the reasons (cache contexts & tags) why this Views
        // block is empty, and can cache it accordingly.
        if (empty($output['view_build'])) {
            $output = [
                '#cache' => $output['#cache'],
            ];
        }
        return $output;
    }
    return [];
}