BlockPageVariant.php
Same filename in other branches
Namespace
Drupal\block\Plugin\DisplayVariantFile
-
core/
modules/ block/ src/ Plugin/ DisplayVariant/ BlockPageVariant.php
View source
<?php
namespace Drupal\block\Plugin\DisplayVariant;
use Drupal\block\BlockRepositoryInterface;
use Drupal\Core\Block\MainContentBlockPluginInterface;
use Drupal\Core\Block\TitleBlockPluginInterface;
use Drupal\Core\Block\MessagesBlockPluginInterface;
use Drupal\Core\Cache\CacheableMetadata;
use Drupal\Core\Display\PageVariantInterface;
use Drupal\Core\Entity\EntityViewBuilderInterface;
use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
use Drupal\Core\Display\VariantBase;
use Symfony\Component\DependencyInjection\ContainerInterface;
/**
* Provides a page display variant that decorates the main content with blocks.
*
* To ensure essential information is displayed, each essential part of a page
* has a corresponding block plugin interface, so that BlockPageVariant can
* automatically provide a fallback in case no block for each of these
* interfaces is placed.
*
* @see \Drupal\Core\Block\MainContentBlockPluginInterface
* @see \Drupal\Core\Block\MessagesBlockPluginInterface
*
* @PageDisplayVariant(
* id = "block_page",
* admin_label = @Translation("Page with blocks")
* )
*/
class BlockPageVariant extends VariantBase implements PageVariantInterface, ContainerFactoryPluginInterface {
/**
* The block repository.
*
* @var \Drupal\block\BlockRepositoryInterface
*/
protected $blockRepository;
/**
* The block view builder.
*
* @var \Drupal\Core\Entity\EntityViewBuilderInterface
*/
protected $blockViewBuilder;
/**
* The Block entity type list cache tags.
*
* @var string[]
*/
protected $blockListCacheTags;
/**
* The render array representing the main page content.
*
* @var array
*/
protected $mainContent = [];
/**
* The page title: a string (plain title) or a render array (formatted title).
*
* @var string|array
*/
protected $title = '';
/**
* Constructs a new BlockPageVariant.
*
* @param array $configuration
* A configuration array containing information about the plugin instance.
* @param string $plugin_id
* The plugin ID for the plugin instance.
* @param mixed $plugin_definition
* The plugin implementation definition.
* @param \Drupal\block\BlockRepositoryInterface $block_repository
* The block repository.
* @param \Drupal\Core\Entity\EntityViewBuilderInterface $block_view_builder
* The block view builder.
* @param string[] $block_list_cache_tags
* The Block entity type list cache tags.
*/
public function __construct(array $configuration, $plugin_id, $plugin_definition, BlockRepositoryInterface $block_repository, EntityViewBuilderInterface $block_view_builder, array $block_list_cache_tags) {
parent::__construct($configuration, $plugin_id, $plugin_definition);
$this->blockRepository = $block_repository;
$this->blockViewBuilder = $block_view_builder;
$this->blockListCacheTags = $block_list_cache_tags;
}
/**
* {@inheritdoc}
*/
public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
return new static($configuration, $plugin_id, $plugin_definition, $container->get('block.repository'), $container->get('entity_type.manager')
->getViewBuilder('block'), $container->get('entity_type.manager')
->getDefinition('block')
->getListCacheTags());
}
/**
* {@inheritdoc}
*/
public function setMainContent(array $main_content) {
$this->mainContent = $main_content;
return $this;
}
/**
* {@inheritdoc}
*/
public function setTitle($title) {
$this->title = $title;
return $this;
}
/**
* {@inheritdoc}
*/
public function build() {
// Track whether blocks showing the main content and messages are displayed.
$main_content_block_displayed = FALSE;
$messages_block_displayed = FALSE;
$build = [
'#cache' => [
'tags' => $this->blockListCacheTags,
],
];
// Load all region content assigned via blocks.
$cacheable_metadata_list = [];
foreach ($this->blockRepository
->getVisibleBlocksPerRegion($cacheable_metadata_list) as $region => $blocks) {
/** @var \Drupal\block\BlockInterface[] $blocks */
foreach ($blocks as $key => $block) {
$block_plugin = $block->getPlugin();
if ($block_plugin instanceof MainContentBlockPluginInterface) {
$block_plugin->setMainContent($this->mainContent);
$main_content_block_displayed = TRUE;
}
elseif ($block_plugin instanceof TitleBlockPluginInterface) {
$block_plugin->setTitle($this->title);
}
elseif ($block_plugin instanceof MessagesBlockPluginInterface) {
$messages_block_displayed = TRUE;
}
$build[$region][$key] = $this->blockViewBuilder
->view($block);
// The main content block cannot be cached: it is a placeholder for the
// render array returned by the controller. It should be rendered as-is,
// with other placed blocks "decorating" it. Analogous reasoning for the
// title block.
if ($block_plugin instanceof MainContentBlockPluginInterface || $block_plugin instanceof TitleBlockPluginInterface) {
unset($build[$region][$key]['#cache']['keys']);
}
}
if (!empty($build[$region])) {
// \Drupal\block\BlockRepositoryInterface::getVisibleBlocksPerRegion()
// returns the blocks in sorted order.
$build[$region]['#sorted'] = TRUE;
}
}
// If no block that shows the main content is displayed, still show the main
// content. Otherwise the end user will see all displayed blocks, but not
// the main content they came for.
if (!$main_content_block_displayed) {
$build['content']['system_main'] = $this->mainContent;
}
// If no block displays status messages, still render them.
if (!$messages_block_displayed) {
$build['content']['messages'] = [
'#weight' => -1000,
'#type' => 'status_messages',
'#include_fallback' => TRUE,
];
}
// If any render arrays are manually placed, render arrays and blocks must
// be sorted.
if (!$main_content_block_displayed || !$messages_block_displayed) {
unset($build['content']['#sorted']);
}
// The access results' cacheability is currently added to the top level of the
// render array. This is done to prevent issues with empty regions being
// displayed.
// This would need to be changed to allow caching of block regions, as each
// region must then have the relevant cacheable metadata.
$merged_cacheable_metadata = CacheableMetadata::createFromRenderArray($build);
foreach ($cacheable_metadata_list as $cacheable_metadata) {
$merged_cacheable_metadata = $merged_cacheable_metadata->merge($cacheable_metadata);
}
$merged_cacheable_metadata->applyTo($build);
return $build;
}
}
Classes
Title | Deprecated | Summary |
---|---|---|
BlockPageVariant | Provides a page display variant that decorates the main content with blocks. |
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