block_subtitle.module in Block Subtitle 8

Adding subtitle to blocks.

File

block_subtitle.module

<?php

/**
 * @file
 * Adding subtitle to blocks.
 */
use Drupal\Core\Form\FormStateInterface;
use Drupal\block\Entity\Block;
use Drupal\Component\Utility\Html;
use Drupal\Core\Routing\RouteMatchInterface;
use Drupal\block\BlockInterface;
use Drupal\Core\Url;

/**
 * Implements hook_help().
 */
function block_subtitle_help($route_name, RouteMatchInterface $route_match) {
  switch ($route_name) {

    // Main module help for the forms_to_email module.
    case 'help.page.block_subtitle':
      $output = '';
      $output .= '<h3>' . t('About') . '</h3>';
      $output .= '<p>' . t("Block Subtitle allows users to add subtitle to any block through the block's configuration interface.") . '</p>';
      $output .= '<h3>' . t('Installation note') . '</h3>';
      $output .= '<dl>';
      $output .= '<dt>' . t('Enable the module on <a href=":extend_link">extend menu</a>.', [
        ':extend_link' => Url::fromRoute('system.modules_list')
          ->toString(),
      ]) . '</dt>';
      $output .= '</dl>';
      $output .= '<h3>' . t('Usage') . '</h3>';
      $output .= '<dl>';
      $output .= '<dt>' . t("To add a subtitle to a block, simply visit that block's configuration page at Administration > Structure > Block Layout and click on Configure of the desired block.") . '</dt>';
      $output .= '</dl>';
      return $output;
  }
}

/**
 * Implements hook_ENTITY_TYPE_presave().
 */
function block_subtitle_block_presave(BlockInterface $entity) {
  if (empty($entity
    ->getThirdPartySetting('block_subtitle', 'subtitle'))) {
    $entity
      ->unsetThirdPartySetting('block_subtitle', 'subtitle');
  }
}

/**
 * Implements hook_form_FORM_ID_alter() for block_form.
 */
function block_subtitle_form_block_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  if (\Drupal::currentUser()
    ->hasPermission('administer block subtitle')) {

    /** @var \Drupal\block\BlockInterface $block */
    $block = $form_state
      ->getFormObject()
      ->getEntity();

    // This will automatically be saved in the third party settings.
    $form['block_subtitle_text'] = [
      '#type' => 'textfield',
      '#title' => t('Subtitle'),
      '#description' => t('Subtitle for the block. Leave blank if you do not need a subtitle.'),
      '#default_value' => $block
        ->getThirdPartySetting('block_subtitle', 'subtitle'),
    ];
    $form['#entity_builders'][] = 'block_subtitle_block_form_builder';
  }
}

/**
 * Entity builder for the contact form edit form with third party options.
 */
function block_subtitle_block_form_builder($entity_type, BlockInterface $block, &$form, FormStateInterface $form_state) {
  $block
    ->setThirdPartySetting('block_subtitle', 'subtitle', $form_state
    ->getValue('block_subtitle_text'));
}

/**
 * Implements hook_preprocess_HOOK().
 */
function block_subtitle_preprocess_block(&$variables) {

  // Blocks coming from page manager widget does not have id.
  if (!empty($variables['elements']['#id'])) {
    $block = Block::load($variables['elements']['#id']);
    if ($block && ($subtitle = $block
      ->getThirdPartySetting('block_subtitle', 'subtitle'))) {
      $variables['subtitle'] = $subtitle;
    }
  }
}

Functions

Name	Description
block_subtitle_block_form_builder	Entity builder for the contact form edit form with third party options.
block_subtitle_block_presave	Implements hook_ENTITY_TYPE_presave().
block_subtitle_form_block_form_alter	Implements hook_form_FORM_ID_alter() for block_form.
block_subtitle_help	Implements hook_help().
block_subtitle_preprocess_block	Implements hook_preprocess_HOOK().