Attachment.php

<?php

/**
 * @file
 * Definition of Drupal\views\Plugin\views\display\Attachment.
 */
namespace Drupal\views\Plugin\views\display;

use Drupal\views\ViewExecutable;
use Drupal\Component\Annotation\Plugin;
use Drupal\Core\Annotation\Translation;

/**
 * The plugin that handles an attachment display.
 *
 * Attachment displays are secondary displays that are 'attached' to a primary
 * display. Effectively they are a simple way to get multiple views within
 * the same view. They can share some information.
 *
 * @ingroup views_display_plugins
 *
 * @Plugin(
 *   id = "attachment",
 *   title = @Translation("Attachment"),
 *   help = @Translation("Attachments added to other displays to achieve multiple views in the same view."),
 *   theme = "views_view",
 *   contextual_links_locations = {""}
 * )
 */
class Attachment extends DisplayPluginBase {

  /**
   * Whether the display allows the use of a pager or not.
   *
   * @var bool
   */
  protected $usesPager = FALSE;
  protected function defineOptions() {
    $options = parent::defineOptions();
    $options['displays'] = array(
      'default' => array(),
    );
    $options['attachment_position'] = array(
      'default' => 'before',
    );
    $options['inherit_arguments'] = array(
      'default' => TRUE,
      'bool' => TRUE,
    );
    $options['inherit_exposed_filters'] = array(
      'default' => FALSE,
      'bool' => TRUE,
    );
    $options['inherit_pager'] = array(
      'default' => FALSE,
      'bool' => TRUE,
    );
    $options['render_pager'] = array(
      'default' => FALSE,
      'bool' => TRUE,
    );
    return $options;
  }
  public function execute() {
    return $this->view
      ->render($this->display['id']);
  }
  public function attachmentPositions($position = NULL) {
    $positions = array(
      'before' => t('Before'),
      'after' => t('After'),
      'both' => t('Both'),
    );
    if ($position) {
      return $positions[$position];
    }
    return $positions;
  }

  /**
   * Provide the summary for attachment options in the views UI.
   *
   * This output is returned as an array.
   */
  public function optionsSummary(&$categories, &$options) {

    // It is very important to call the parent function here:
    parent::optionsSummary($categories, $options);
    $categories['attachment'] = array(
      'title' => t('Attachment settings'),
      'column' => 'second',
      'build' => array(
        '#weight' => -10,
      ),
    );
    $displays = array_filter($this
      ->getOption('displays'));
    if (count($displays) > 1) {
      $attach_to = t('Multiple displays');
    }
    elseif (count($displays) == 1) {
      $display = array_shift($displays);
      if ($display = $this->view->storage
        ->getDisplay($display)) {
        $attach_to = check_plain($display['display_title']);
      }
    }
    if (!isset($attach_to)) {
      $attach_to = t('Not defined');
    }
    $options['displays'] = array(
      'category' => 'attachment',
      'title' => t('Attach to'),
      'value' => $attach_to,
    );
    $options['attachment_position'] = array(
      'category' => 'attachment',
      'title' => t('Attachment position'),
      'value' => $this
        ->attachmentPositions($this
        ->getOption('attachment_position')),
    );
    $options['inherit_arguments'] = array(
      'category' => 'attachment',
      'title' => t('Inherit contextual filters'),
      'value' => $this
        ->getOption('inherit_arguments') ? t('Yes') : t('No'),
    );
    $options['inherit_exposed_filters'] = array(
      'category' => 'attachment',
      'title' => t('Inherit exposed filters'),
      'value' => $this
        ->getOption('inherit_exposed_filters') ? t('Yes') : t('No'),
    );
    $options['inherit_pager'] = array(
      'category' => 'pager',
      'title' => t('Inherit pager'),
      'value' => $this
        ->getOption('inherit_pager') ? t('Yes') : t('No'),
    );
    $options['render_pager'] = array(
      'category' => 'pager',
      'title' => t('Render pager'),
      'value' => $this
        ->getOption('render_pager') ? t('Yes') : t('No'),
    );
  }

  /**
   * Provide the default form for setting options.
   */
  public function buildOptionsForm(&$form, &$form_state) {

    // It is very important to call the parent function here:
    parent::buildOptionsForm($form, $form_state);
    switch ($form_state['section']) {
      case 'inherit_arguments':
        $form['#title'] .= t('Inherit contextual filters');
        $form['inherit_arguments'] = array(
          '#type' => 'checkbox',
          '#title' => t('Inherit'),
          '#description' => t('Should this display inherit its contextual filter values from the parent display to which it is attached?'),
          '#default_value' => $this
            ->getOption('inherit_arguments'),
        );
        break;
      case 'inherit_exposed_filters':
        $form['#title'] .= t('Inherit exposed filters');
        $form['inherit_exposed_filters'] = array(
          '#type' => 'checkbox',
          '#title' => t('Inherit'),
          '#description' => t('Should this display inherit its exposed filter values from the parent display to which it is attached?'),
          '#default_value' => $this
            ->getOption('inherit_exposed_filters'),
        );
        break;
      case 'inherit_pager':
        $form['#title'] .= t('Inherit pager');
        $form['inherit_pager'] = array(
          '#type' => 'checkbox',
          '#title' => t('Inherit'),
          '#description' => t('Should this display inherit its paging values from the parent display to which it is attached?'),
          '#default_value' => $this
            ->getOption('inherit_pager'),
        );
        break;
      case 'render_pager':
        $form['#title'] .= t('Render pager');
        $form['render_pager'] = array(
          '#type' => 'checkbox',
          '#title' => t('Render'),
          '#description' => t('Should this display render the pager values? This is only meaningful if inheriting a pager.'),
          '#default_value' => $this
            ->getOption('render_pager'),
        );
        break;
      case 'attachment_position':
        $form['#title'] .= t('Position');
        $form['attachment_position'] = array(
          '#type' => 'radios',
          '#description' => t('Attach before or after the parent display?'),
          '#options' => $this
            ->attachmentPositions(),
          '#default_value' => $this
            ->getOption('attachment_position'),
        );
        break;
      case 'displays':
        $form['#title'] .= t('Attach to');
        $displays = array();
        foreach ($this->view->storage
          ->get('display') as $display_id => $display) {
          if ($this->view->displayHandlers
            ->has($display_id) && $this->view->displayHandlers
            ->get($display_id)
            ->acceptAttachments()) {
            $displays[$display_id] = $display['display_title'];
          }
        }
        $form['displays'] = array(
          '#type' => 'checkboxes',
          '#description' => t('Select which display or displays this should attach to.'),
          '#options' => $displays,
          '#default_value' => $this
            ->getOption('displays'),
        );
        break;
    }
  }

  /**
   * Perform any necessary changes to the form values prior to storage.
   * There is no need for this function to actually store the data.
   */
  public function submitOptionsForm(&$form, &$form_state) {

    // It is very important to call the parent function here:
    parent::submitOptionsForm($form, $form_state);
    switch ($form_state['section']) {
      case 'displays':
        $form_state['values'][$form_state['section']] = array_filter($form_state['values'][$form_state['section']]);
      case 'inherit_arguments':
      case 'inherit_pager':
      case 'render_pager':
      case 'inherit_exposed_filters':
      case 'attachment_position':
        $this
          ->setOption($form_state['section'], $form_state['values'][$form_state['section']]);
        break;
    }
  }

  /**
   * Attach to another view.
   */
  public function attachTo(ViewExecutable $view, $display_id) {
    $displays = $this
      ->getOption('displays');
    if (empty($displays[$display_id])) {
      return;
    }
    if (!$this
      ->access()) {
      return;
    }
    $args = $this
      ->getOption('inherit_arguments') ? $this->view->args : array();
    $view
      ->setArguments($args);
    $view
      ->setDisplay($this->display['id']);
    if ($this
      ->getOption('inherit_pager')) {
      $view->display_handler->usesPager = $this->view->displayHandlers
        ->get($display_id)
        ->usesPager();
      $view->display_handler
        ->setOption('pager', $this->view->displayHandlers
        ->get($display_id)
        ->getOption('pager'));
    }
    $attachment = $view
      ->executeDisplay($this->display['id'], $args);
    switch ($this
      ->getOption('attachment_position')) {
      case 'before':
        $this->view->attachment_before[] = $attachment;
        break;
      case 'after':
        $this->view->attachment_after[] = $attachment;
        break;
      case 'both':
        $this->view->attachment_before[] = $attachment;
        $this->view->attachment_after[] = $attachment;
        break;
    }
  }

  /**
   * Attachment displays only use exposed widgets if
   * they are set to inherit the exposed filter settings
   * of their parent display.
   */
  public function usesExposed() {
    if (!empty($this->options['inherit_exposed_filters']) && parent::usesExposed()) {
      return TRUE;
    }
    return FALSE;
  }

  /**
   * If an attachment is set to inherit the exposed filter
   * settings from its parent display, then don't render and
   * display a second set of exposed filter widgets.
   */
  public function displaysExposed() {
    return $this->options['inherit_exposed_filters'] ? FALSE : TRUE;
  }
  public function renderPager() {
    return $this
      ->usesPager() && $this
      ->getOption('render_pager');
  }

}