Example Module for Londug Intro to Drupal Modules (2014/04/22)

README.md

Sandwich Module

This gist contains sample code for use in lessons.

sandwich.admin.inc

<?php
/**
 * @file
 * Admin pages for the Sandwiches module.
 */

/**
 * Form constructor for the sandwich admin form.
 *
 * @ingroup forms
 */
function sandwich_admin($form, &$form_state) {

  $sudo_state = array(
    'visible' => array(
      ':input[name="sandwich_advanced_mode"]' => array('checked' => TRUE),
      ':input[name="sandwich_custom_mustard"]' => array('error' => TRUE),
    ),
  );

  $form['sandwich_vegetarian_only'] = array(
    '#title' => t('Vegetarian Only'),
    '#description' => t('Hide non-vegetarian sandwiches.'),
    '#default_value' => variable_get('sandwich_vegetarian_only', FALSE),
    '#type' => 'checkbox',
  );

  $form['sandwich_advanced_mode'] = array(
    '#title' => t('Use Sudo'),
    '#description' => t('Force more sandwiches.'),
    '#default_value' => variable_get('sandwich_advanced_mode', FALSE),
    '#type' => 'checkbox',
  );

  $form['sandwich_no_crusts'] = array(
    '#title' => t('No Crusts'),
    '#description' => t('Cuts the crusts off.'),
    '#default_value' => variable_get('sandwich_no_crusts', FALSE),
    '#type' => 'checkbox',
    '#states' => $sudo_state,
  );

  $form['sandwich_custom_mustard'] = array(
    '#title' => t('Custom mustard brand'),
    '#default_value' => variable_get('sandwich_custom_mustard', FALSE),
    '#type' => 'textfield',
    '#states' => $sudo_state,
  );

  return system_settings_form($form);
}

/**
 * Validation callback for sandwich admin form.
 *
 * @ingroup forms
 */
function sandwich_admin_validate($form, &$form_state) {
  $values = $form_state['values'];

  if (!$values['sandwich_advanced_mode']) {
    if ($values['sandwich_custom_mustard']) {
      form_set_error('sandwich_custom_mustard', 'You\'re not sudo!');
    }
    if ($values['sandwich_no_crusts']) {
      form_set_error('sandwich_no_crusts', 'You\'re not sudo!');
    }
  }
}

sandwich.info

name = Sandwiches
description = Lists sandwiches
core = 7.x
package = other
version = 0.3
configure = admin/config/sandwich

sandwich.module

<?php
/**
 * @file
 * Sandwiches module.
 */

/**
 * Implements hook_menu().
 */
function sandwich_menu() {
  $items = array();

  $items['admin/config/sandwich'] = array(
    'title' => 'Configure Sandwiches',
    'description' => 'Allows sandwich-related settings to be adjusted.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('sandwich_admin'),
    'access arguments' => array('administer sandwiches'),
    'file' => 'sandwich.admin.inc',
  );

  return $items;
}

/**
 * Implements hook_permission().
 */
function sandwich_permission() {
  return array(
    'administer sandwiches' => array(
      'title' => t('Administer sandwiches'),
      'restrict access' => TRUE,
    ),
  );
}