fieldblock.module in Field as Block 7

Allow fields to be rendered in blocks.

File

fieldblock.module

<?php

/**
 * @file
 * Allow fields to be rendered in blocks.
 */
define('FIELDBLOCK_STORAGE_STATIC', 'fieldblock_storage');

/**
 * Implements hook_module_implements_alter().
 */
function fieldblock_module_implements_alter(&$implementations, $hook) {

  // Move these hooks to the end of the execution list. Even though Fieldblock only implements
  // hook_entity_view_alter, module_implements() indexes them by first-called, which is the most
  // specific, so we need those too.
  $view_alter_hooks = array(
    'entity_view_alter',
    'node_view_alter',
    'taxonomy_term_alter',
    'user_view_alter',
  );
  if (in_array($hook, $view_alter_hooks) && isset($implementations['fieldblock'])) {
    $group = $implementations['fieldblock'];
    unset($implementations['fieldblock']);
    $implementations['fieldblock'] = $group;
  }
}

/**
 * Implements hook_form_alter().
 * Adds a column to the "display fields" table-form, with a checkbox for each
 * field.
 */
function fieldblock_form_field_ui_display_overview_form_alter(&$form, &$form_state, $form_id) {
  $entity_type = $form['#entity_type'];
  $bundle = $form['#bundle'];
  $view_mode = $form['#view_mode'];
  $variable_name = 'fieldblock-' . $entity_type . '-' . $bundle . '-' . $view_mode;
  $settings = variable_get($variable_name, array());

  // Add a column header.
  $form['fields']['#header'][] = t('Display as block');

  // Add checkboxes.
  $field_names = array_merge($form['#fields'], $form['#extra']);
  foreach ($field_names as $field_name) {
    $form['fields'][$field_name]['fieldblock'] = array(
      '#type' => 'checkbox',
      '#default_value' => isset($settings[$field_name]) ? true : false,
      '#title' => '',
    );
  }

  // Add a submit handler.
  $form['#submit'][] = 'fieldblock_field_display_submit';
}

/**
 * Form submit handler for field_ui_display_overview_form.
 * Saves a single variable for each entity + bundle + view mode combination if
 * a field has been made available as block. Having separate variables makes the
 * configuration more flexible for exporting with strongarm and features.
 */
function fieldblock_field_display_submit($form, &$form_state) {
  $entity_type = $form['#entity_type'];
  $bundle = $form['#bundle'];
  $view_mode = $form['#view_mode'];
  $variable_name = 'fieldblock-' . $entity_type . '-' . $bundle . '-' . $view_mode;
  $settings = array();
  foreach ($form_state['values']['fields'] as $field_name => $field) {
    if (!empty($field['fieldblock'])) {
      $settings[$field_name] = $form['fields'][$field_name]['human_name']['#markup'];
    }
  }
  if (empty($settings)) {

    // This variable may have existed before, so let's clean up a little.
    variable_del($variable_name);
  }
  else {
    variable_set($variable_name, $settings);
    drupal_set_message(t('One or more fields have been made available as block. Do not forget to assign the block(s) to a region.'));
  }
}

/**
 * Implements hook_block_info().
 */
function fieldblock_block_info() {
  $blocks = array();
  $fieldblocks = fieldblock_get_block_list();
  foreach ($fieldblocks as $fieldblock_id => $description) {
    $blocks[$fieldblock_id] = array(
      'info' => $description,
      // The block can not be cached, because the content of it (ie. the content
      // of the field displayed in it) may vary based on whatever criteria the
      // fieldblock.module is unaware of. Eg. the same field might be displayed
      // differently for different users, for different roles, for different
      // pages, etc.
      'cache' => DRUPAL_NO_CACHE,
    );
  }
  return $blocks;
}

/**
 * Helper function for fieldblock_block_info().
 * Builds a list of fields that have been made available as a block.
 * @return array
 *   An array with all fields that are made visible via the display fields UI,
 *   in the form of [fieldblock identifier] => [block description].
 */
function fieldblock_get_block_list() {
  $fieldblocks =& drupal_static(__FUNCTION__);
  if (!isset($fieldblocks)) {
    $fieldblocks = array();
    $entities = entity_get_info();

    // Loop over the entity types.
    foreach ($entities as $entity_type => $entity_info) {

      // Loop over each entity type's bundles.
      foreach ($entity_info['bundles'] as $bundle => $bundle_info) {
        $view_modes = field_view_mode_settings($entity_type, $bundle);

        // Treat the default settings as a real view mode with custom settings.
        $view_modes['default']['custom_settings'] = true;

        // Loop over the bundle's view modes.
        foreach ($view_modes as $view_mode => $view_mode_info) {

          // Ignore this view mode if its custom settings are not enabled.
          if (!$view_mode_info['custom_settings']) {
            continue;
          }

          // Get the settings from the stored variable.
          $variable_name = 'fieldblock-' . $entity_type . '-' . $bundle . '-' . $view_mode;
          $fieldblock_settings = variable_get($variable_name, array());

          // Loop over the fields defined in the variable.
          foreach ($fieldblock_settings as $field_name => $field_label) {

            // Build the fieldblock info.
            $fieldblock_id = md5($variable_name . '-' . $field_name);
            $fieldblocks[$fieldblock_id] = t('@field field (from @type: @bundle: @view_mode)', array(
              '@field' => $field_label,
              '@type' => $entity_type,
              '@bundle' => $bundle_info['label'],
              '@view_mode' => $view_mode,
            ));
          }
        }
      }
    }
  }
  return $fieldblocks;
}

/**
 * Implements hook_block_view().
 * Retrieves a field, identified by the block delta, from the static cache.
 */
function fieldblock_block_view($delta = '') {
  $block = array();
  $fieldblocks_storage =& drupal_static(FIELDBLOCK_STORAGE_STATIC);
  if (isset($fieldblocks_storage[$delta])) {

    // If the field has a label, use it as block title and hide it on the
    // field itself.
    $block['subject'] = '';
    if (isset($fieldblocks_storage[$delta]['#label_display']) && $fieldblocks_storage[$delta]['#label_display'] != 'hidden') {
      $block['subject'] = $fieldblocks_storage[$delta]['#title'];
      $fieldblocks_storage[$delta]['#label_display'] = 'hidden';
    }
    $block['content'] = $fieldblocks_storage[$delta];
    $block['fieldblock_name'] = $fieldblocks_storage[$delta]['fieldblock_name'];
  }
  return $block;
}

/**
 * Implements hook_entity_view_alter().
 * Stores fields attached to the current entity in a static cache, to be
 * retrieved in fieldblock_block_view, and hides the field from the renderable
 * array.
 */
function fieldblock_entity_view_alter(&$build, $type) {

  // Do nothing if essential information is missing.
  if (!isset($build['#bundle'], $build['#entity_type'], $build['#view_mode'])) {
    return;
  }
  $entity_type = $build['#entity_type'];
  $bundle = $build['#bundle'];
  $view_mode = $build['#view_mode'];

  // Check whether the view mode uses custom display settings or the 'default'
  // mode.
  $view_mode_settings = field_view_mode_settings($entity_type, $bundle);
  $actual_mode = !empty($view_mode_settings[$view_mode]['custom_settings']) ? $view_mode : 'default';
  $fieldblocks_storage =& drupal_static(FIELDBLOCK_STORAGE_STATIC);
  $variable_name = 'fieldblock-' . $entity_type . '-' . $bundle . '-' . $actual_mode;
  $fieldblock_settings = variable_get($variable_name, array());

  // Loop over the fieldblocks for this entity + bundle + view mode combination
  // and store the field's render array for later use.
  foreach ($fieldblock_settings as $field_name => $field_label) {
    if (isset($build[$field_name])) {
      $fieldblock_name = $variable_name . '-' . $field_name;
      $fieldblock_id = md5($fieldblock_name);
      $fieldblocks_storage[$fieldblock_id] = $build[$field_name];
      hide($build[$field_name]);
      $fieldblocks_storage[$fieldblock_id]['fieldblock_name'] = $fieldblock_name;
    }
  }
}

/**
 * Give fieldblocks a meaningful html id in spite of the hashed block deltas.
 */
function fieldblock_preprocess_block(&$variables) {
  if ($variables['block']->module == 'fieldblock') {
    $variables['block_html_id'] = drupal_html_id('block-' . $variables['block']->fieldblock_name);
  }
}

Functions

Name	Description
fieldblock_block_info	Implements hook_block_info().
fieldblock_block_view	Implements hook_block_view(). Retrieves a field, identified by the block delta, from the static cache.
fieldblock_entity_view_alter	Implements hook_entity_view_alter(). Stores fields attached to the current entity in a static cache, to be retrieved in fieldblock_block_view, and hides the field from the renderable array.
fieldblock_field_display_submit	Form submit handler for field_ui_display_overview_form. Saves a single variable for each entity + bundle + view mode combination if a field has been made available as block. Having separate variables makes the configuration more flexible for exporting…
fieldblock_form_field_ui_display_overview_form_alter	Implements hook_form_alter(). Adds a column to the "display fields" table-form, with a checkbox for each field.
fieldblock_get_block_list	Helper function for fieldblock_block_info(). Builds a list of fields that have been made available as a block.
fieldblock_module_implements_alter	Implements hook_module_implements_alter().
fieldblock_preprocess_block	Give fieldblocks a meaningful html id in spite of the hashed block deltas.

Constants

Name	Description
FIELDBLOCK_STORAGE_STATIC	@file Allow fields to be rendered in blocks.