Dev Notes

Various Cheat Sheets and Resources by David Egan/Carawebs.

Bootstrap Carousel with Indicators Navigation for WordPress


ACF, Bootstrap, PHP, WordPress, jQuery
David Egan

A Bootstrap carousel with dual indicators/controls for WordPress. Populated by ACF “relationship” field.

Indicators

This carousel has two sets of indicators - a set of numbers, and an un-numbered “standard” set of indicators.

It needs a bit of work to have the active class attached properly to the second set of indicators.

This is achieved by:

  • Giving a unique class name to these indicators (e.g. class="no-numbers")
  • Testing the contained list items data-slide-to= against the currently displayed item

Building the Carousels - ACF

The carousel content is built from an ACF “relationship” field, which is used to create a custom WordPress loop. In this case, the relationship field is used to create a loop of “report” custom post types.

This PHP function builds the carousel. The code could be added to the theme custom.php file. I usually keep custom loops in a unique file for ease of editing, and require_once this file in functions.php.

/*==============================================================================
  Case Studies for Services Mobile
  ============================================================================*/
function carawebs_reports_mobile() {

    $relationship_field = 'related'; // This could be passed into the function

    $posts = get_field($relationship_field);

    if ($posts) {
      ?>
      <div id="mobile-reports-carousel" class="carousel slide" data-ride="carousel">
      <!-- Indicators -->
        <ol class="carousel-indicators numbered list-unstyled list-inline">
          <?php

          $item_count = 0; // Start up a count
          foreach ( $posts as $post) { // Loop through the array

            ?>
            <li data-target="#mobile-reports-carousel" data-slide-to="<?php echo $item_count; ?>"><?php echo $item_count + 1; ?></li>
            <?php
            $item_count++;

          } ?>
        </ol>
        <div id="carousel-count"></div><!-- output carousel index & total number of slides for debugging, set by jQuery function -->
        <ol class="carousel-indicators no-numbers">
          <?php

          $item_count = 0;
          foreach ( $posts as $post) {

            ?>
            <li data-target="#mobile-reports-carousel" data-slide-to="<?php echo $item_count; ?>"></li><?php
            $item_count++;

          } ?>
      </ol>
      <div class="carousel-inner">
        <?php
        $number = 0;
        foreach ( $posts as $post) { // variable must be called $post (IMPORTANT)

        global $post;
        setup_postdata($post);

        ?>
        <div class="item counter-<?php echo $number; ?>">
          <?php
          // custom function to bring in the 'medium' featured image
          carawebs_featured_image ('medium'); ?>
          <h4><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h4>
          <div class="post_content"><?php the_content(); ?></div>
          <?php
          // Another custom field - builds a ul of file downloads
          carawebs_download_link_repeater(); ?>
        </div>

      <?php
      $number++;
      } ?>
      </div>
    </div>
    <?php

    // Restore original Post Data
    wp_reset_postdata();

    }
}

This carousel needed to replace a more elaborate slider at small screen sizes.

<section>
    <div class="row report-downloads">
      <h2 class="text-center">Report Downloads</h2>

      <?php

        // This function returns 'true' for mobile phones
        if (carawebs_is_phone()=='true'){

          // If this is a mobile phone
          // --------------------------
          // #innovations--section-toggle & #innovation-content set up for collapse in /assets/js/_frontpage-toggles.js
          ?><div id="reports-mobile" class="row">
            <?php carawebs_reports_mobile(); ?>
          </div><?php

        } else {

          // The device is NOT a phone
          // Hide at small screens using CSS - target #reports-desktop
          // --------------------------
          ?>
          <div id="reports-desktop">

              <?php carawebs_reports_desktop(); ?>

          </div>
          <?php

          // Add the mobile view stuff here to allow a mobile-type view on contracted desktops
          // ---------------------------
          ?>
          <div id="reports-mobile-visible">
            <div class="col-xs-14 col-xs-offset-1">
              <?php carawebs_reports_mobile(); ?>
            </div>

          </div><?php

        }

      ?>

    </div>
</section><!-- /.report-downloads -->

The “check for phone” function:

/*==============================================================================
  Detect Phones
  ============================================================================*/
function carawebs_is_phone() {

	$useragent=$_SERVER['HTTP_USER_AGENT'];
	if(preg_match('/(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino/i',$useragent)||preg_match('/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i',substr($useragent,0,4)))
	return true;
}

See here for lioghtweight phone detection strings: http://detectmobilebrowsers.com/. This might be a useful phone detecting class: https://github.com/serbanghita/Mobile-Detect/.

For the non-phone case, the relevant divs are shown/hidden by means of CSS.

jQuery

Controls are built into /js/_carousel.js:

/*==============================================================================
    Set up - give first items emphasis classes.
    Necessary because the slider is built dynamically
==============================================================================*/

   $("#mobile-reports-carousel .carousel-indicators li:first").addClass("active");
   $("#mobile-reports-carousel .carousel-indicators.no-numbers li:first").addClass("active");

   // Give active class to the first carousel item
   $("#mobile-reports-carousel .item:first").addClass("active");

   // Prevent auto play
   $('#mobile-reports-carousel').carousel({ interval: false });

/*==============================================================================
    Listen to the 'slid carousel' event to trigger code after each slide change
==============================================================================*/
$('#case-studies-carousel').on('slid.bs.carousel', function () {

  // For debugging...
  //alert("We have SLID!!! Thank God it's working...");

  // Useful variables
  var carouselData = $(this).data('bs.carousel');
  // get current index the Bootstrap way...
  var currentIndex = carouselData.getItemIndex(carouselData.$element.find('.item.active'));
  var total = carouselData.$items.length;

  // ...get the current index the jQuery way...
  var itemIndex = $(".item.active");
  var jCurrentIndex = itemIndex.index();

  // For debugging: needs a #carousel-count div in the markup
  var text = ( "Index: " + jCurrentIndex );
  $('#carousel-count').text(text);

  // Using bs method, getItemIndex - see: https://github.com/twbs/bootstrap/issues/14215
  //$('.carousel-indicators.no-numbers [data-slide-to=' + currentIndex + ']').addClass('active');//

  // Pure jQuery method - attach the active class to the indicator corresponding to the current item
  // -----------------------------------
  $('.carousel-indicators.no-numbers [data-slide-to=' + jCurrentIndex + ']').addClass('active');

});

Mobile Swipe Support

For mobile swipe support, use the touchSwipe jQuery plugin. This plugin is copyright (c) 2010 Matt Bryson and is dual licensed under the MIT or GPL Version 2 licenses.


comments powered by Disqus