Anatomy of an HTML5 WordPress theme

This site has been written in HTML5 and used to use WordPress to manage the content. I’ll explain why I used HTML5, describe the structure of the theme templates, and show some of the ways I tried to tame WordPress’s tendency to add mess to the source code.

As this is my personal site I wanted to experiment with using HTML5, CSS3, and WAI-ARIA. All these documents are currently working drafts and subject to change. However, the web documents and applications of the future are going to be written in HTML5 and I wanted to see the benefits of using it to markup static documents. Using CSS 2.1, let alone the CSS3 selectors and properties that some browser vendors have implemented, has many advantages for controlling the presentation of semantically coded documents. For this reason I am not going to avoid using basic CSS 2.1 selectors just to faithfully reproducing this site’s design in IE6. However, I have tried to accommodate IE 7 and IE 8 users by using an HTML5 enabling script so that the new HTML5 elements can be styled in those browsers if users have Javascript enabled.

HTML5 templates

I started with a static prototype of this site developed on my local server. WordPress makes it very easy to create your own templates and, therefore, it is no problem to use HTML5. This theme only has 3 main templates: index, single, and archive. There are of course templates for 404s, attachments, comments, etc., but I won’t discuss them as they are all based on the 3 main templates. All the templates include ARIA roles as an accessibility aide.

The single.php template has this rough structure:

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title></title>
  <link rel="stylesheet" href="default.css">
</head>

<body>
  <header role="banner"></header>
  <nav role="navigation"></nav>
  <article role="main">
    <header>
      <time datetime="YYYY-MM-DD"></time>
      <h1></h1>
    </header>
    <footer></footer>
  </article>
  <nav></nav>
  <aside role="complementary"></aside>
  <footer role="contentinfo">
    <small></small>
  </footer>
</body>
</html>

The first line of the document is the HTML5 DOCTYPE. The new <article> element contains the content of each post. The same structure is used for the index.php template except that there are several articles displayed on each page and the ARIA role value of main is not used. In contrast, the archive.php template houses all the article excerpts in a <section> element with the ARIA role of main because the list of archived posts is itself the main content of the document.

A clean theme

WordPress tends to add classes, elements, and other bits of code in certain places. I haven’t used any of the WordPress functions that add class names to the body and to elements wrapping a post and also wanted to avoid cluttering the source code with any other unnecessary markup. This required a bit of fiddling around with the theme’s functions.php file. I’m not a PHP developer so this might not be pretty!

Removing actions from wp_head()

WordPress has a hook called wp_head that sits in the header.php of most themes. To avoid it inserting unwanted code into the <head> of the document I used the remove_action function to disable the functions that were responsible. The following code was added to the functions.php file of my theme:

// Remove links to the extra feeds (e.g. category feeds)
remove_action( 'wp_head', 'feed_links_extra', 3 );
// Remove links to the general feeds (e.g. posts and comments)
remove_action( 'wp_head', 'feed_links', 2 );
// Remove link to the RSD service endpoint, EditURI link
remove_action( 'wp_head', 'rsd_link' );
// Remove link to the Windows Live Writer manifest file
remove_action( 'wp_head', 'wlwmanifest_link' );
// Remove index link
remove_action( 'wp_head', 'index_rel_link' );
// Remove prev link
remove_action( 'wp_head', 'parent_post_rel_link', 10, 0 );
// Remove start link
remove_action( 'wp_head', 'start_post_rel_link', 10, 0 );
// Display relational links for adjacent posts
remove_action( 'wp_head', 'adjacent_posts_rel_link', 10, 0 );
// Remove XHTML generator showing WP version
remove_action( 'wp_head', 'wp_generator' );

Source: WPEngineer.com: Cleanup WordPress Header

Removing an empty <span>

If you want to create excerpts you can either write them into the excerpt box or use the <--more--> quicktag in the WordPress editor. I just wanted the first paragraph of my posts to be used as the excerpt and so using the in-editor tag was the most practical approach I was aware of. However, when you do this WordPress will insert an empty <span> in the post’s content. This element has an id so that the area following the excerpt can be targeted by “more” or “continue reading” links. I removed both the empty <span> and the jump link by adding the following code to the functions.php file of the theme:

// removes empty span
function remove_empty_read_more_span($content) {
  return eregi_replace("(<p><span id=\"more-[0-9]{1,}\"></span></p>)", "", $content);
}
add_filter('the_content', 'remove_empty_read_more_span');

Source: Ganda Manurung: Remove Empty Span Tag On WordPress

// removes url hash to avoid the jump link
function remove_more_jump_link($link) {
  $offset = strpos($link, '#more-');
  if ($offset) {
    $end = strpos($link, '"',$offset);
  }
  if ($end) {
    $link = substr_replace($link, '', $offset, $end-$offset);
  }
  return $link;
}
add_filter('the_content_more_link', 'remove_more_jump_link');

Source: WordPress Codex: Customizing the Read More

Displaying images in the excerpt

For posts that display nothing but a photograph (yes, they will be shit but I’m hoping it gets me using my camera a bit more often) I wanted the image to show up in the archives. Equally, if the first paragraph of a post contained a link I wanted that to be preserved. The default the_excerpt() template tag doesn’t allow for this so it needed some modifying. I added a new function, which is just a modified version of the core excerpt function, to the functions.php file and then made sure that the template tag executed this function rather than the one contained in the core WordPress files.

function improved_trim_excerpt($text) {
   if ( '' == $text ) {
      $text = get_the_content('');
      $text = strip_shortcodes( $text );
      $text = apply_filters('the_content', $text);
      $text = str_replace(']]>', ']]&amp;gt;', $text);
      $text = strip_tags($text, '<p><img><a>');
      $excerpt_length = apply_filters('excerpt_length', 55);
      $words = explode(' ', $text, $excerpt_length + 1);
      if (count($words) > $excerpt_length) {
         array_pop($words);
         array_push($words, '[...]');
         $text = implode(' ', $words);
         $text = force_balance_tags($text);
      }
   }
   return $text;
}
remove_filter('get_the_excerpt', 'wp_trim_excerpt');
add_filter('get_the_excerpt', 'improved_trim_excerpt');

Source: Aaron Russell: Improving WordPress’ the_excerpt() template tag

I prefer not to have empty elements in the markup and so I needed a way to conditionally insert the “Older entries”, “Newer Entries”, etc., links into templates. The solution I’m using here, which isn’t perfect, is to add this to functions.php:

function show_posts_nav() {
  global $wp_query;
  return ($wp_query->max_num_pages > 1);
}

Source: Eric Martin: Conditional navigation links in WordPress

And then to wrap the navigation markup in the templates with the following:

<?php if (show_posts_nav()) : ?>
<nav>
   <ul>
      <li><?php next_posts_link('&#171; Older Entries') ?></li>
      <li><?php previous_posts_link('Newer Entries &#187;') ?></li>
   </ul>
</nav>
<?php endif; ?>

Summary

It’s fairly easy to create a simple site with HTML5 and to use WordPress to deliver it. At the moment there are issues with Internet Explorer because you cannot style HTML5 elements unless you use Javascript. However, HTML5 redefines the meaning of certain elements (such as <dl>, which has become a more versatile “description list”) and allows block elements to be wrapped in a link. Therefore, there is still benefit in using the HTML5 DOCTYPE even if you do not make use of the new elements.

Further reading

  1. HTML5 working draft
  2. HTML5 differences from HTML4
  3. Accessible Rich Internet Applications (WAI-ARIA) 1.0