Drupal 8.0.0 beta 12. More info: https://www.drupal.org/node/2514176

core/modules/views/src/DisplayPluginCollection.php

@@ -0,0 +1,114 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\views\DisplayPluginCollection.
+ */
+
+namespace Drupal\views;
+
+use Drupal\Component\Plugin\Exception\PluginException;
+use Drupal\Component\Plugin\PluginManagerInterface;
+use Drupal\Core\Plugin\DefaultLazyPluginCollection;
+
+/**
+ * A class which wraps the displays of a view so you can lazy-initialize them.
+ */
+class DisplayPluginCollection extends DefaultLazyPluginCollection {
+
+  /**
+   * Stores a reference to the view which has this displays attached.
+   *
+   * @var \Drupal\views\ViewExecutable
+   */
+  protected $view;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected $pluginKey = 'display_plugin';
+
+  /**
+   * Constructs a DisplayPluginCollection object.
+   *
+   * @param \Drupal\views\ViewExecutable
+   *   The view which has this displays attached.
+   * @param \Drupal\Component\Plugin\PluginManagerInterface $manager
+   *   The manager to be used for instantiating plugins.
+   */
+  public function __construct(ViewExecutable $view, PluginManagerInterface $manager) {
+    parent::__construct($manager, $view->storage->get('display'));
+
+    $this->view = $view;
+    $this->initializePlugin('default');
+  }
+
+  /**
+   * Destructs a DisplayPluginCollection object.
+   */
+  public function __destruct() {
+    $this->clear();
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * @return \Drupal\views\Plugin\views\display\DisplayPluginBase
+   */
+  public function &get($instance_id) {
+    return parent::get($instance_id);
+  }
+
+  /**
+   * Overrides \Drupal\Component\Plugin\LazyPluginCollection::clear().
+   */
+  public function clear() {
+    foreach (array_filter($this->pluginInstances) as $display) {
+      $display->destroy();
+    }
+
+    parent::clear();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function initializePlugin($display_id) {
+    // Retrieve and initialize the new display handler with data.
+    $display = &$this->view->storage->getDisplay($display_id);
+
+    try {
+      $this->configurations[$display_id] = $display;
+      parent::initializePlugin($display_id);
+    }
+    // Catch any plugin exceptions that are thrown. So we can fail nicely if a
+    // display plugin isn't found.
+    catch (PluginException $e) {
+      $message = $e->getMessage();
+      drupal_set_message(t('@message', array('@message' => $message)), 'warning');
+    }
+
+    // If no plugin instance has been created, return NULL.
+    if (empty($this->pluginInstances[$display_id])) {
+      return NULL;
+    }
+
+    $this->pluginInstances[$display_id]->initDisplay($this->view, $display);
+    // If this is not the default display handler, let it know which is since
+    // it may well use some data from the default.
+    if ($display_id != 'default') {
+      $this->pluginInstances[$display_id]->default_display = $this->pluginInstances['default'];
+    }
+  }
+
+  /**
+   * Overrides \Drupal\Component\Plugin\LazyPluginCollection::remove().
+   */
+  public function remove($instance_id) {
+    $this->get($instance_id)->remove();
+
+    parent::remove($instance_id);
+  }
+
+
+}