field_display_label.module in Field Display Label 8

Main file for Field Display Label module.

File

field_display_label.module

<?php

/**
 * @file
 * Main file for Field Display Label module.
 */
use Drupal\Core\Config\Entity\ThirdPartySettingsInterface;
use Drupal\Core\Form\FormStateInterface;

/**
 * Implements hook_form_FORM_ID_alter() for field_config_edit_form().
 */
function field_display_label_form_field_config_edit_form_alter(&$form, FormStateInterface $form_state) {
  $field = $form_state
    ->getFormObject()
    ->getEntity();
  if (!isset($field)) {
    return;
  }
  $form['display_label'] = [
    '#type' => 'textfield',
    '#title' => t('Display label'),
    '#description' => t('A separate label for viewing this field. Leave blank to use the default field label.'),
    '#weight' => isset($form['label']['#weight']) ? $form['label']['#weight'] + 1 : 0,
    '#default_value' => !empty($field
      ->getThirdPartySetting('field_display_label', 'display_label')) ? $field
      ->getThirdPartySetting('field_display_label', 'display_label') : '',
  ];
  $form['actions']['submit']['#submit'][] = 'field_display_label_form_field_config_edit_form_submit';
}

/**
 * Form submission handler for form_field_config_edit_form_alter.
 *
 * @param array $form
 *   The form array.
 * @param \Drupal\Core\Form\FormStateInterface $form_state
 *   The form state.
 */
function field_display_label_form_field_config_edit_form_submit(array $form, FormStateInterface $form_state) {
  $field = $form_state
    ->getFormObject()
    ->getEntity();
  $form_fields =& $form_state
    ->getValues();

  // If the label is entered update settings.
  if ($form_fields['display_label']) {
    $field
      ->setThirdPartySetting('field_display_label', 'display_label', $form_fields['display_label']);
    $field
      ->save();
  }
  else {
    $field
      ->unsetThirdPartySetting('field_display_label', 'display_label');
    $field
      ->save();
  }
}

/**
 * Implements hook_preprocess_field().
 */
function field_display_label_preprocess_field(&$variables) {
  $element = $variables['element'];
  $entity = $element['#object'];
  if (empty($entity)) {
    return;
  }
  $field_definition = $entity
    ->getFieldDefinition($element['#field_name']);
  if ($field_definition instanceof ThirdPartySettingsInterface) {
    $definition = $field_definition
      ->getThirdPartySetting('field_display_label', 'display_label');
    if (isset($definition) && !empty($definition)) {
      $variables['label'] = $definition;
    }
  }
}

Functions

Name	Description
field_display_label_form_field_config_edit_form_alter	Implements hook_form_FORM_ID_alter() for field_config_edit_form().
field_display_label_form_field_config_edit_form_submit	Form submission handler for form_field_config_edit_form_alter.
field_display_label_preprocess_field	Implements hook_preprocess_field().