ModuleConfigurationForm.php

<?php

namespace Drupal\wcm8_siteinfo\Form;

use Drupal\Core\Form\ConfigFormBase;
use Drupal\Core\Form\FormStateInterface;

/**
 * Defines a form that configures module settings.
 */
class ModuleConfigurationForm extends ConfigFormBase {

  /**
   * {@inheritdoc}
   */
  public function getFormId() {
    return 'wcm8_siteinfo_admin_settings';
  }

  /**
   * {@inheritdoc}
   */
  protected function getEditableConfigNames() {
    return [
      'wcm8_siteinfo.settings',
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function buildForm(array $form, FormStateInterface $form_state) {
    $config = $this->config('wcm8_siteinfo.settings');
    $site_config = $this->config('system.site');
    $site_name = $site_config->get('name');
    
    $form['siteinfo'] = array(
      '#type' => 'vertical_tabs',
      '#default_tab' => 'edit-basic',
    );
    
    // Basic Information tab
    $form['basic'] = array(
      '#type' => 'details',
      '#title' => $this->t('Basic Information'),
      '#group' => 'siteinfo',
    );
    
    $form['basic']['prefix'] = array(
      '#type' => 'textfield',
      '#title' => $this->t('Site Name Prefix'),
      '#description' => $this->t('The prefix for your site name - for example, <i>Department of</i> ... '),
      '#size' => '60',
      '#maxlength' => '60',
      '#default_value' => $config->get('prefix'),
    );
    
    $form['basic']['site_name'] = array(
      '#type' => 'textfield',
      '#title' => $this->t('Site Name'),
      '#description' => $this->t('Main name for the site - it should be your college, department or organization name.'),
      '#size' => '60',
      '#maxlength' => '75',
      '#default_value' => $site_name,
    );
    
    // Contact Information tab
    $form['contact'] = array(
      '#type' => 'details',
      '#title' => $this->t('Contact Information'),
      '#group' => 'siteinfo',
    );
    
    $form['contact']['address_1'] = array(
      '#type' => 'textfield',
      '#title' => $this->t('Address Line 1'),
      '#description' => $this->t('First line of address. Room number and building if on campus.'),
      '#default_value' => $config->get('address_1'),
    );
    
    $form['contact']['address_2'] = array(
      '#type' => 'textfield',
      '#title' => $this->t('Address Line 2'),
      '#description' => $this->t('Second line of address. Street address if on campus.'),
      '#default_value' => $config->get('address_2'),
    );
    
    $form['contact']['city'] = array(
      '#type' => 'textfield',
      '#title' => $this->t('City'),
      '#default_value' => $config->get('city'),
    );
    
    $form['contact']['state'] = array(
      '#type' => 'textfield',
      '#title' => $this->t('State'),
      '#default_value' => $config->get('state'),
    );
    
    $form['contact']['zip'] = array(
      '#type' => 'textfield',
      '#title' => $this->t('Zip Code'),
      '#default_value' => $config->get('zip'),
    );
    
    $form['contact']['phone'] = array(
      '#type' => 'tel',
      '#title' => $this->t('Phone'),
      '#description' => $this->t('Main contact phone number for your site.'),
      '#default_value' => $config->get('phone'),
    );
    
    $form['contact']['fax'] = array(
      '#type' => 'tel',
      '#title' => $this->t('Fax'),
      '#description' => $this->t('Fax number, if applicable.'),
      '#default_value' => $config->get('fax'),
    );
    
    $form['contact']['contact_email'] = array(
      '#type' => 'email',
      '#title' => $this->t('Email'),
      '#description' => $this->t('Main contact email for your site.'),
      '#default_value' => $config->get('contact_email'),
    );
    
    // Social Networking tab
    $form['social'] = array(
      '#type' => 'details',
      '#title' => $this->t('Social Networking'),
      '#group' => 'siteinfo',
    );
    
    $form['social']['twitter'] = array(
      '#type' => 'textfield',
      '#title' => $this->t('Twitter'),
      '#default_value' => $config->get('twitter'),
    );

    return parent::buildForm($form, $form_state);
  }

  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state) {
    $values = $form_state->getValues();
    $this->config('wcm8_siteinfo.settings')
      ->set('prefix', $values['prefix'])
      ->set('address_1', $values['address_1'])
      ->set('address_2', $values['address_2'])
      ->set('city', $values['city'])
      ->set('state', $values['state'])
      ->set('zip', $values['zip'])
      ->set('phone', $values['phone'])
      ->set('fax', $values['fax'])
      ->set('email', $values['contact_email'])
      ->set('twitter', $values['twitter'])
      ->save();

    parent::submitForm($form, $form_state);
  }

}