Layout.php

<?php

namespace Drupal\Core\Layout\Annotation;

use Drupal\Component\Annotation\Plugin;
use Drupal\Core\Layout\LayoutDefault;
use Drupal\Core\Layout\LayoutDefinition;

/**
 * Defines a Layout annotation object.
 *
 * Layouts are used to define a list of regions and then output render arrays
 * in each of the regions, usually using a template.
 *
 * Plugin namespace: Plugin\Layout
 *
 * @see \Drupal\Core\Layout\LayoutInterface
 * @see \Drupal\Core\Layout\LayoutDefault
 * @see \Drupal\Core\Layout\LayoutPluginManager
 * @see plugin_api
 *
 * @Annotation
 */
class Layout extends Plugin {
    
    /**
     * The plugin ID.
     *
     * @var string
     */
    public $id;
    
    /**
     * The human-readable name.
     *
     * @var string
     *
     * @ingroup plugin_translatable
     */
    public $label;
    
    /**
     * A description for advanced layouts.
     *
     * This property is optional and it does not need to be declared.
     *
     * Sometimes layouts are so complex that the name is insufficient to describe
     * a layout such that a visually impaired administrator could layout a page
     * for a non-visually impaired audience. If specified, it will provide a
     * description that is used for accessibility purposes.
     *
     * @var string
     *
     * @ingroup plugin_translatable
     */
    public $description;
    
    /**
     * The human-readable category.
     *
     * @var string
     *
     * @see \Drupal\Component\Plugin\CategorizingPluginManagerInterface
     *
     * @ingroup plugin_translatable
     */
    public $category;
    
    /**
     * The template file to render this layout (relative to the 'path' given).
     *
     * This property is optional and it does not need to be declared.
     *
     * If specified, then the layout_discovery module will register the template
     * with hook_theme() and the module or theme registering this layout does not
     * need to do it.
     *
     * @var string
     *
     * @see hook_theme()
     */
    public $template;
    
    /**
     * The theme hook used to render this layout.
     *
     * This property is optional and it does not need to be declared.
     *
     * If specified, it's assumed that the module or theme registering this layout
     * will also register the theme hook with hook_theme() itself. This is
     * mutually exclusive with 'template' - you can't specify both.
     *
     * @var string
     *
     * @see hook_theme()
     */
    public $theme_hook = 'layout';
    
    /**
     * Path (relative to the module or theme) to resources like icon or template.
     *
     * This property is optional and it does not need to be declared.
     *
     * @var string
     */
    public $path;
    
    /**
     * The asset library.
     *
     * This property is optional and it does not need to be declared.
     *
     * @var string
     */
    public $library;
    
    /**
     * The path to the preview image (relative to the 'path' given).
     *
     * This property is optional and it does not need to be declared.
     *
     * @var string
     */
    public $icon;
    
    /**
     * The icon map.
     *
     * This property is optional and it does not need to be declared.
     *
     * @var string[][]
     *
     * @see \Drupal\Core\Layout\Icon\IconBuilderInterface::build()
     */
    public $icon_map;
    
    /**
     * An associative array of regions in this layout.
     *
     * The key of the array is the machine name of the region, and the value is
     * an associative array with the following keys:
     * - label: (string) The human-readable name of the region.
     *
     * Any remaining keys may have special meaning for the given layout plugin,
     * but are undefined here.
     *
     * @var array
     */
    public $regions = [];
    
    /**
     * The default region.
     *
     * @var string
     */
    public $default_region;
    
    /**
     * The layout plugin class.
     *
     * This default value is used for plugins defined in layouts.yml that do not
     * specify a class themselves.
     *
     * @var string
     */
    public $class = LayoutDefault::class;
    
    /**
     * {@inheritdoc}
     */
    public function get() {
        return new LayoutDefinition($this->definition);
    }

}