back_to_top.module in Back To Top 8

Adds the back to top button.

File

back_to_top.module

<?php

/**
 * @file
 * Adds the back to top button.
 */

/**
 * Implements hook_page_attachments().
 */
use Drupal\Core\Routing\RouteMatchInterface;

/**
 *
 */
function back_to_top_page_attachments(array &$attachments) {
  $config = \Drupal::config('back_to_top.settings');
  $settings = $config
    ->get();
  $button_settings = [
    'back_to_top_prevent_on_mobile' => $settings['back_to_top_prevent_on_mobile'],
    'back_to_top_prevent_in_admin' => $settings['back_to_top_prevent_in_admin'],
    'back_to_top_button_type' => $settings['back_to_top_button_type'],
    'back_to_top_button_text' => $settings['back_to_top_button_text'],
  ];
  if ($settings['back_to_top_prevent_on_mobile'] && is_mobile()) {
    return FALSE;
  }
  if ($settings['back_to_top_prevent_in_admin'] && is_adminpage()) {
    return FALSE;
  }
  if ($settings['back_to_top_prevent_in_front'] && \Drupal::service('path.matcher')
    ->isFrontPage()) {
    return FALSE;
  }
  $attachments['#attached']['library'][] = 'back_to_top/back_to_top_js';
  $attachments['#attached']['drupalSettings']['back_to_top']['back_to_top_button_trigger'] = $settings['back_to_top_button_trigger'];

  // Add stylesheet for image or text/css button.
  if ($settings['back_to_top_button_type'] == "text") {
    $attachments['#attached']['library'][] = 'back_to_top/back_to_top_text';
  }
  else {
    $attachments['#attached']['library'][] = 'back_to_top/back_to_top_icon';
  }
  $css = '';
  $hover_css = '';

  // Check variables and add placement.
  if ($settings['back_to_top_button_place'] == 2) {
    $css .= "left: 10px; ";
  }
  if ($settings['back_to_top_button_place'] == 3) {
    $css .= "left: 50%; margin-left: -50px;";
  }
  if ($settings['back_to_top_button_place'] == 4) {
    $css .= "top: 10px;";
  }
  if ($settings['back_to_top_button_place'] == 5) {
    $css .= "top: 10px; left: 10px;";
  }
  if ($settings['back_to_top_button_place'] == 6) {
    $css .= "top: 10px; left: 50%; margin-left: -50px;";
  }
  if ($settings['back_to_top_button_place'] == 7) {
    $css .= "top: 50%;";
  }
  if ($settings['back_to_top_button_place'] == 8) {
    $css .= "top: 50%; left: 10px;";
  }
  if ($settings['back_to_top_button_place'] == 9) {
    $css .= "top: 50%; left: 50%; margin-left: -50px;";
  }

  // Check variables and add color from settings - this code could be done a bit nicer.
  if ($settings['back_to_top_button_type'] == "text" && $settings['back_to_top_bg_color'] !== '#F7F7F7') {
    $css .= "background: " . $settings['back_to_top_bg_color'] . ";";
  }
  if ($settings['back_to_top_button_type'] == "text" && $settings['back_to_top_border_color'] !== '#CCCCCC') {
    $css .= "border-color: " . $settings['back_to_top_border_color'] . ";";
  }
  if ($settings['back_to_top_button_type'] == "text" && $settings['back_to_top_hover_color'] !== '#EEEEEE') {
    $hover_css .= "body #backtotop:hover { background: " . $settings['back_to_top_hover_color'] . "; border-color: " . $settings['back_to_top_hover_color'] . "; }";
  }
  if ($settings['back_to_top_button_type'] == "text" && $settings['back_to_top_text_color'] !== '#333333') {
    $css .= "color: " . $settings['back_to_top_text_color'] . ";";
  }
  if ($css != '') {
    $attachments['#attached']['html_head'][] = [
      [
        '#tag' => 'style',
        '#value' => 'body #backtotop {' . $css . '}' . $hover_css,
      ],
      'css',
    ];
  }

  // Add settings to js.
  $attachments['#attached']['drupalSettings']['back_to_top'] += $button_settings;
}

/**
 * Check if mobile or touch device with PHP so javascript and css isn't included in that case.
 */
function is_mobile() {

  // Check for mobile device using Browscap module if it is available.
  if (\Drupal::moduleHandler()
    ->moduleExists('browscap')) {
    $browser = \Drupal::service('browscap')
      ->getBrowser();
    if (isset($browser['ismobiledevice']) && $browser['ismobiledevice'] == 1) {
      return TRUE;
    }
  }
  if (isset($_SERVER["HTTP_X_WAP_PROFILE"])) {
    return TRUE;
  }
  if (isset($_SERVER["HTTP_ACCEPT"]) && preg_match("/wap\\.|\\.wap/i", $_SERVER["HTTP_ACCEPT"])) {
    return TRUE;
  }
  if (isset($_SERVER["HTTP_USER_AGENT"])) {
    $user_agents = [
      "midp",
      "j2me",
      "iphone",
      "avantg",
      "docomo",
      "novarra",
      "palmos",
      "palmsource",
      "240x320",
      "opwv",
      "chtml",
      "pda",
      "windows\\ ce",
      "mmp\\/",
      "blackberry",
      "mib\\/",
      "symbian",
      "wireless",
      "nokia",
      "hand",
      "mobi",
      "phone",
      "cdm",
      "up\\.b",
      "audio",
      "sie\\-",
      "sec\\-",
      "samsung",
      "htc",
      "mot\\-",
      "mitsu",
      "sagem",
      "sony",
      "alcatel",
      "lg",
      "erics",
      "vx",
      "^nec",
      "philips",
      "mmm",
      "xx",
      "panasonic",
      "sharp",
      "wap",
      "sch",
      "rover",
      "pocket",
      "benq",
      "java",
      "pt",
      "pg",
      "vox",
      "amoi",
      "bird",
      "compal",
      "kg",
      "voda",
      "sany",
      "kdd",
      "dbt",
      "sendo",
      "sgh",
      "gradi",
      "jb",
      "\\d\\d\\di",
      "moto",
      "ipad",
      "android",
      "ipod",
      "webos",
    ];
    foreach ($user_agents as $user_string) {
      if (preg_match("/" . $user_string . "/i", strtolower($_SERVER["HTTP_USER_AGENT"]))) {
        return TRUE;
      }
    }
  }
  return FALSE;
}

/**
 * Check if page viewed is in admin section or a node/edit for possible option to not include javascript and css in that case.
 */
function is_adminpage() {
  $route = \Drupal::routeMatch()
    ->getRouteObject();
  $is_admin = \Drupal::service('router.admin_context')
    ->isAdminRoute($route);

  // Alter for admin prevent check.
  \Drupal::moduleHandler()
    ->alter('back_to_top_admin_prevent', $is_admin);
  return $is_admin;
}

/**
 * Implements hook_help().
 */
function back_to_top_help($route_name, RouteMatchInterface $route_match) {
  switch ($route_name) {
    case 'help.page.back_to_top':
      $text = file_get_contents(dirname(__FILE__) . "/README.txt");
      if (!\Drupal::moduleHandler()
        ->moduleExists('markdown')) {
        return '<pre>' . $text . '</pre>';
      }
      else {

        // Use the Markdown filter to render the README.
        $filter_manager = \Drupal::service('plugin.manager.filter');
        $settings = \Drupal::configFactory()
          ->get('markdown.settings')
          ->getRawData();
        $config = [
          'settings' => $settings,
        ];
        $filter = $filter_manager
          ->createInstance('markdown', $config);
        return $filter
          ->process($text, 'en');
      }
  }
  return NULL;
}

Functions

Name	Description
back_to_top_help	Implements hook_help().
back_to_top_page_attachments
is_adminpage	Check if page viewed is in admin section or a node/edit for possible option to not include javascript and css in that case.
is_mobile	Check if mobile or touch device with PHP so javascript and css isn't included in that case.