If you are new to WordPress and are still experimenting with the permalink structure to best fit your needs, you might consider using this function to create internal links for your site. Using the URL generated by the_shortlink() will always resolve correctly, using the verbose URL of the permalink structure may cause issues if you change the structure and do not manually edit all the internal links you have previously posted.

Please note, by “internal links” I am refering to the links used within the content of a post or page on your site pointing to another post or page on your site. A WordPress installation has the “smarts” to correctly resolve the links it generates if you change the permalink structure but it will not go back and “fix” anything you manually typed yourself as part of your page or post entry.

There is great potential for the user, the designer, and the developer using this function. I recommend adding it to all themes. Here is the most basic default usage of the_shortlink():

<?php the_shortlink(); ?>

This is the code I have decided to use on this site:

<?php the_shortlink( __('Short Link'), '', ' &#124; ', '' ); ?>

… which you can see just after the comments or subscribe link in the post meta details.

Of course you can always use the ‘Get Shortlink’ button found on the page and post administration panels to get your shortlink, but making use of this single line of code allows your readers to gain that same benefit, too.

Let’s start with the same basic outline and list the default options for each function. We will start with wp_nav_menu() ¹ first:

wp_nav_menu( array(
    'menu'              => '',
    'container'         => 'div',
    'container_class'   => '',
    'container_id'      => '',
    'menu_class'        => 'menu',
    'menu_id'           => '',
    'echo'              => true,
    'fallback_cb'       => 'wp_page_menu',
    'before'            => '',
    'after'             => '',
    'link_before'       => '',
    'link_after'        => '',
    'depth'             => 0,
    'walker'            => '',
    'theme_location'    => ''
    ) );

We follow with wp_list_categories() ^{2, 3} which is often wrapped in a <ul class=”menu”> tag:

<ul class="menu">
wp_list_categories( array(
    'include'           => '',
    'exclude'           => '',
    'exclude_tree'      => '',
    'child_of'          => 0,
    'hide_empty'        => 1,
    'orderby'           => 'name',
    'order'             => 'ASC',
    'use_desc_for_title'=> 1,
    'number'            => NULL,
    'hierarchical'      => true,
    'show_count'        => 0,
    'pad_counts'        => 0,
    'style'             => 'list',
    /* 'style' set to list "creates list items for an unordered list" */
    'show_option_all'   => '',
    'show_option_none'  => __('No categories'),
    'show_last_update'  => 0,
    'feed'              => '',
    'feed_type'         => '',
    'feed_image'        => '',
    'current_category'  => 0,
    'taxonomy'          => 'category',
    'title_li'          => __( '' ),
    /* 'title_li' set to '' for menus from the default 'Categories' */
    'echo'              => 1,
    'depth'             => 0,
    'walker'            => 'Walker_Category'
    ) );
</ul>

Here is the break-down of the wp_list_categories() default options from above:

• 'include' – not used
• 'exclude' – not used
• 'exclude_tree' – not used
• 'child_of' – not used
• 'hide_empty' – not used
• 'orderby' – not used
• 'order' – not used
• 'use_desc_for_title' – not used
• 'number' – not used
• 'hierarchical' – not used
• 'show_count' – not used
• 'pad_counts' – not used
• 'style' – not used
• 'show_option_all' – not available
• 'show_option_none' – not available
• 'show_last_update' – not available
• 'feed' – not available
• 'feed_type' – not available
• 'feed_image' – not available
• 'current_category' – not available
• 'taxonomy' – not available
• 'title_li' – not used
• 'echo' – similar to wp_nav_menu(); true versus 1 as value
• 'depth' – same as wp_nav_menu()
• 'walker' – see below for additional notes

Although there are great many options available to be used with wp_list_categoires() most are not used (as noted in the list above) in place of the user interface of wp_nav_menu() found under Appearance | Menu in the dashboard. The options that are marked as “not available” are currently not directly supported by wp_nav_menu() without the application of filters. The last few options remaining match up almost exactly with wp_page_nav() in a similar fashion as was shown with wp_list_pages().

Just like the wp_list_pages() consideration, the wp_nav_menu() fallback_cb option may be set to 'fallback_cb' => 'wp_list_categories'. This backward compatibility may also be addressed with a custom function as was noted, too.

Note: In most cases you would leave the wp_nav_menu() 'walker' option set to its default NULL although wp_list_categories() uses its own default walker class.

Like the last post in the series we will look at the default arguments used by each function, starting with wp_nav_menu() ¹:

wp_nav_menu( array(
    'menu'              => '',
    'container'         => 'div',
    'container_class'   => '',
    'container_id'      => '',
    'menu_class'        => 'menu',
    'menu_id'           => '',
    'echo'              => true,
    'fallback_cb'       => 'wp_page_menu',
    'before'            => '',
    'after'             => '',
    'link_before'       => '',
    'link_after'        => '',
    'depth'             => 0,
    'walker'            => '',
    'theme_location'    => ''
    ) );

The following is a default “menu” version of wp_list_pages() ^{2, 3}, often wrapped within a <ul class=”menu”> tag:

<ul class="menu">
<?php wp_list_pages( array(
    'sort_column'       => 'menu_order, post_title',
    'include'           => '',
    'exclude'           => '',
    'exclude_tree'      => '',
    'child_of'          => 0,
    'show_date'         => '',
    'date_format'       => get_option('date_format'),
    'title_li'          => __(''),
    /* 'title_li' set to '' for menus from the default 'Pages' */
    'authors'           => '',
    'echo'              => 1,
    'link_before'       => '',
    'link_after'        => '',
    'depth'             => 0,
    'walker'            => ''
    ) ); ?>
</ul>

Here is the break-down of the wp_list_pages() default options from above:

• 'sort_column' – not used
• 'include' – not used
• 'exclude' – not used
• 'exclude_tree' – not used
• 'child_of' – not used
• 'show_date' – not used
• 'date_format' – not used
• 'title_li' – not used, see below for additional notes
• 'authors' – not used
• 'echo' – similar to wp_nav_menu(); true versus 1 as value
• 'link_before' – same as wp_nav_menu()
• 'link_after' – same as wp_nav_menu()
• 'depth' – same as wp_nav_menu()
• 'walker' – same as wp_nav_menu()

Similar to wp_page_menu(), the ‘sort_column’, ‘include’, ‘exclude’, ‘exclude_tree’, and ‘child_of’ are replaced via the end-user’s specific choices. The ‘show_date’ and its related ‘date_format’ option, as well as the ‘author’ argument, are not available within the default wp_nav_menu() structure. Once again, the balance of the default options in wp_list_pages() matches the defaults found in wp_nav_menu().

Also consider setting the wp_nav_menu() fallback_cb option to 'fallback_cb' => 'wp_list_pages'. This backward compatibility may also be addressed with a custom function as posted by Nicolas Kuttler.

Note: If the 'title_li' => __('') option was being used it may also require the removal of the wrapping <ul> tag in the existing menu structure created with wp_list_pages().

This post will be dealing with function arguments in common between wp_nav_menu() and wp_page_menu(). Follow-up posts will be covering wp_list_pages() and wp_list_categories(). I will not be covering the specific use for each function’s arguments; the idea is to help show how these options correlate to one another.

Let’s start with the full default of wp_nav_menu() ¹ explicitly displayed:

wp_nav_menu( array(
    'menu'              => '',
    'container'         => 'div',
    'container_class'   => '',
    'container_id'      => '',
    'menu_class'        => 'menu',
    'menu_id'           => '',
    'echo'              => true,
    'fallback_cb'       => 'wp_page_menu',
    'before'            => '',
    'after'             => '',
    'link_before'       => '',
    'link_after'        => '',
    'depth'             => 0,
    'walker'            => '',
    'theme_location'    => ''
    ) );

Followed by the same explicit defaults of wp_page_menu() ^{2, 3}:

wp_page_menu( array(
    'sort_column'       => 'menu_order, post_title',
    'include'           => '',
    'exclude'           => '',
    'show_home'         => false,
    'menu_class'        => 'menu',
    'echo'              => true,
    'link_before'       => '',
    'link_after'        => ''
    ) );

Now onto updating wp_page_menu() to wp_nav_menu(), which turns out to be rather simple.

Here is the break-down of the wp_page_menu() default options from above:

• 'sort_column' – not used
• 'include' – not used
• 'exclude' – not used
• 'show_home' – not used (see bonus section below)
• 'menu_class' – same as wp_nav_menu()
• 'echo' – same as wp_nav_menu()
• 'link_before' – same as wp_nav_menu()
• 'link_after' – same as wp_nav_menu()

First off ‘sort_column’, ‘include’, and ‘exclude’ are replaced by the end-user’s choices using the UI of wp_nav_menu() found under Appearance | Menu in the dashboard. The balance of the default options are the same in wp_nav_menu(), with the exception of 'show_home' => false which is the “bonus” content.

Upgrading from wp_page_menu() to wp_nav_menu() may be as easy as a simple find and replace operation.

// Modified Post - requires WordPress version 3.0 or greater
function modified_post(){
  global $wp_version;
  if (version_compare($wp_version, "2.999", ">")) {
    /* If the post date and the last modified date are different display modified post details */
    if ( get_the_date() <> get_the_modified_date() ) {
      echo '<div class="modified-post">'; /* CSS wrapper for modified post details */
      echo 'Last modified by ' . get_the_modified_author() . ' on ' . get_the_modified_date();
      echo '</div><!-- .modified-post -->';
    }
  }
}

Of course, you may have noticed the check for WordPress version 3.0 or greater. This is required as the function get_the_date() on line 6 is currently only found in versions of WordPress starting at 3.0

Once the above code has been added to your functions.php file and you are using a version of WordPress greater than or equal to 3.0 then all you need to do is drop the following line of code inside the loop of the template file you want to display the modified post details on.

<?php modified_post(); ?>

Also included is a CSS class element for easy styling. The code can be easily edited to add more elements, too.

Now, what good is this little bit of code? Have a look around and see it in action.

Using the default definition from the register_sidebar() function found in ../wp-includes/widgets.php of WordPress version 3.0-alpha 3.0-beta1² (see below):

	$defaults = array(
		'name' => sprintf(__('Sidebar %d'), $i ),
		'id' => "sidebar-$i",
		'description' => '',
		'before_widget' => '<li id="%1$s" class="widget %2$s">',
		'after_widget' => "</li>\n",
		'before_title' => '<h2 class="widgettitle">',
		'after_title' => "</h2>\n",
	);

… and the default Navigation Menu widget, the following CSS style elements are generated:

• #nav-menu-<widget instance>
• .widget
• .widget_nav_menu
• .widgettitle

… with these elements generated specifically by the wp_nav_menu() function found in ../wp-includes/default-widgets.php of WordPress version 3.0-alpha 3.0-beta1²:

• .menu-<menu name>-container²
• #menu-<menu name>
• .menu
• #menu-item-<unique identifier*>
• .menu-item-type-<types: page, category, Custom>¹
• .menu-item²
• .menu-item-type-<post_type, custom, or taxonomy>²
• .menu-item-object-<page, or category>²
• .current_page_item
• .sub-menu¹

This is just an initial listing of my observations as of the March 16, 2010 3.0-alpha version of WordPress. Look for future updates; and, please feel free to make note of your own observations below.

Bonus – A suggested addition to style.css for theme developers:

/* WordPress 3.0 Navigation Menu default widget */
.widget_nav_menu .menu {margin: 0;}
.widget_nav_menu .menu li {
  display: block;
  float: none;
  /* text-align: left; */
}

Copyright © 2010 WP First Aid All rights reserved.

Which begs the question, what about those posts made before the year 2010? This is where a dynamic copyright function would come in very handy. It would be more correct to have this display in the footer:

Copyright © 2009-2010 WP First Aid All rights reserved.

Most WordPress themes will include, at a minimum, code that will generate a current year copyright statement, perhaps something along these lines:

<?php _e( 'Copyright &copy; ' ); ?>
<?php echo date( 'Y' ); ?>
<strong> <?php bloginfo( 'name' ); ?> </strong>
<?php _e( 'All rights reserved.' ); ?>

To make this code into a function and add some dynamics lets start with a simple PHP construct:

function dynamic_copyright() {
  // code goes here
}

To get the first year a post was written on the blog we need to find the first post. This can be done with this code snippet:

  $all_posts = get_posts( 'order=ASC' );
  $first_post = $all_posts[0];
  $first_date = $first_post->post_date_gmt;

We started by getting all of the posts with the get_posts() function. We assigned the first post, which is found at index 0 (zero) to its own variable. Then we assign that post’s date (in GMT) to its own variable.

We now have isolated the date of the first post on the blog and can perform further operations on it. The basic dynamic part of the function is complete. If the first post is removed and the “new” first post has a different date, then the above snippet will simply use the new post’s date.

The balance of the function is only a slight modification of the original “minimum” sample code from above:

  _e( 'Copyright © ' );
  echo substr( $first_date, 0 ,4 ) . "-" . date( 'Y' );
  echo ' <strong>' . get_bloginfo( 'name' ) . '</strong> ';
  _e( 'All rights reserved.' );

The key is highlighted at line 6. We echo, or display, the first four characters of the $first_date string which is the year; add a hyphen; and, then call a standard PHP function to add the current year as a four digit representation.

Here is the entire dynamic_copyright() function, including comments:

function bns_dynamic_copyright() {
  /* Get all posts */
  $all_posts = get_posts( 'post_status=publish&order=ASC' );
  /* Get first post */
  $first_post = $all_posts[0];
  /* Get date of first post */
  $first_date = $first_post->post_date_gmt;

  /* Display common footer copyright notice */
  _e( 'Copyright © ' );
  /* Display first post year and current year */
  if ( substr( $first_date, 0, 4 ) == date( 'Y' ) ) {
  /* Only display current year if no posts in previous years */
    echo date( 'Y' );
  } else {
    echo substr( $first_date, 0, 4 ) . "-" . date( 'Y' );
  }
  /* Display blog name from 'General Settings' page */
  echo ' <strong>' . get_bloginfo( 'name' ) . '</strong> ';
  _e( 'All rights reserved.' );
}

Of course, this function is compliments of BuyNowShop.com and has their customary bns prefix as it will be appearing in all of their themes.

Just like I did, you can copy and paste the entire sample bns_dynamic_copyright() code above into your theme’s functions.php file; then, replace the code in your theme’s footer.php file that generates your old static copyright notice with this line of code:

<?php bns_dynamic_copyright(); ?>

Your theme will now display a dynamic copyright notice as you continue your writings for many years to come. Congratulations!

A snippet of the Profile screen

NB: This tip is offered under the premise you are using a self-hosted installation of WordPress and your web host provider has installed the cPanel application to allow you to manage your web site.

Let’s start …

1. Access the cPanel for your web site; and, locate the phpMyAdmin applet, it is generally found in the Databases section.
2. Start phpMyAdmin.
3. Locate and access your WordPress database.
4. Find the wp_users table

wp_users table in your WordPress database

Next, click on the left most icon to browse the users in the wp_users table.

The user list

Then, click on the “pencil” icon beside the user you wish to edit. This will display the screen we will be using to change the username.

The edit user screen

Now, edit the user_login (and the user_nicename) to your new login username. Click on the “GO” button in the bottom right corner (not shown in the image) of the edit screen. Voila!

You can now change the username in a WordPress self-hosted installation. Well Done!

PS: Applying this technique using other methods to access the database is possible, this one only deals with using the cPanel / phpMyAdmin combination.

PPS: Remember to make back-ups! Always!

Here is the trac ticket: http://core.trac.wordpress.org/ticket/11414, so it is being addressed.

In the meantime, I have decided to install the Ajax Calendar plugin as a substitute. There are many other calendar plugins available but this one suits my current needs.

Using a sample plugin (download zip file below) I will show you a simple how-to that makes use of the_widget() function. There is no codex page at WordPress.org for this function as of this writing, but there are some references you can find:

• WordPress trac ticket #9701
• WordPress trunk reference

The “trunk” reference provides an easy to follow layout of the function:

the_widget (line 1291 in file ../wp-includes/widget.php)

Output an arbitrary widget as a template tag

    * since: 2.8

void the_widget (string $widget, [array $instance = array()], [array $args = array()])

    * string $widget: the widget's PHP class name (see default-widgets.php)
    * array $instance: the widget's instance settings
    * array $args: the widget's sidebar args

We are going to use the sample plugin to replace the values in the function. We will start with this:

<?php /* Using the_widget() to make a plugin template tag */
the_widget(
  string $widget,
  $instance = array(),
  $args = array ()
);
/* NB: This will not work ... yet! */ ?>

First we will replace the “string $widget” with the plugin class name (see line 19):

<?php
/*
Plugin Name: WPFirstAid Sample Widget
Plugin URI: http://wpfirstaid.com
Description: Plugin with multi-widget functionality that displays stuff ...
Version: 0.1
Author: Edward Caissie
Author URI: http://edwardcaissie.com/
*/

/* Add function to the widgets_init hook. */
add_action( 'widgets_init', 'load_my_wpfa_sample_widget' );

/* Function that registers our widget. */
function load_my_wpfa_sample_widget() {
	register_widget( 'WPFA_Sample_Widget' );
}

class WPFA_Sample_Widget extends WP_Widget {

	function WPFA_Sample_Widget() {
      /* Widget settings. */
  		$widget_ops = array('classname' => 'wpfa-sample', 'description' => __('Displays some stuff.'));
  		/* Widget control settings. */
  		$control_ops = array('width' => 200, 'height' => 200, 'id_base' => 'wpfa-sample');
  		/* Create the widget. */
  		$this->WP_Widget('wpfa-sample', 'WPFirstAid Sample', $widget_ops, $control_ops);
  	}

	function widget( $args, $instance ) {

The function now looks like this:

<?php /* Using the_widget() to make a plugin template tag */
the_widget(
  WPFA_Sample_Widget,
  $instance = array(),
  $args = array ()
);
/* NB: This will not work ... yet! */ ?>

Next we will replace the “$instance = array()” part of the function with the appropriate code from the sample (see lines 70-75), in this sample case simply start with the “$defaults” values:

	function widget( $args, $instance ) {
      extract( $args );
      /* User-selected settings. */
      $title        = apply_filters('widget_title', $instance['title'] );
      $choices      = $instance['choices'];
      $show_choices = $instance['show_choices'];
      $optionals    = $instance['optionals'];

      /* Before widget (defined by themes). */
      echo $before_widget;

      /* Title of widget (before and after defined by themes). */
      if ( $title )
        echo $before_title . $title . $after_title;

      /* Display stuff based on widget settings. */
      if ( $show_choices ) {
        echo $choices . ' is in ... step to your ' . $optionals;
      } else {
        echo __('No appointments today');
      }

      /* After widget (defined by themes). */
      echo $after_widget;
  }

	function update( $new_instance, $old_instance ) {
      $instance = $old_instance;

      /* Strip tags (if needed) and update the widget settings. */
      $instance['title']          = strip_tags( $new_instance['title'] );
      $instance['choices']        = strip_tags( $new_instance['choices'] );
      $instance['show_choices']   = $new_instance['show_choices'];
      $instance['optionals']      = $new_instance['optionals'];

      return $instance;
  }

  function form( $instance ) {
      /* Set default widget settings. */
      $defaults = array(
          'title'                 => __('WPFirstAid Sample'),
          'choices'               => 'The Doctor',
          'show_choices'          => true,
          'optionals'             => 'right'
      );
      $instance = wp_parse_args( (array) $instance, $defaults );
		?>

		<p>
			<label for="<?php echo $this->get_field_id( 'title' ); ?>"><?php _e('Title:'); ?></label>

The function now looks like this:

<?php /* Using the_widget() to make a plugin template tag */
the_widget(
  WPFA_Sample_Widget,
  $instance = array(
        'title'                 => __('WPFirstAid Sample'),
        'choices'               => 'The Doctor',
        'show_choices'          => true,
        'optionals'             => 'right'
  ),
  $args = array ()
);
/* NB: This will not work ... yet! */ ?>

Now we just need to replace the last parameter, “$args = array()” with the appropriate information. Depending on the theme, and whether or not there exists widget areas in the theme, the simplest place to start is with clearing the standard widget arguments that reference before and after the widget, as well as before and after the widget title. The function will now look like this:

<?php /* Using the_widget() to make a plugin template tag */
the_widget(
  WPFA_Sample_Widget,
  $instance = array(
        'title'                 => __('WPFirstAid Sample'),
        'choices'               => 'The Doctor',
        'show_choices'          => true,
        'optionals'             => 'right'
  ),
  $args = array (
  'before_widget'   => '',
  'before_title'    => '',
  'after_title'     => '',
  'after_widget'    => ''
  )
);
/* NB: This will work, now! */ ?>

Just copy and paste into your theme; and, after making suitable changes to match your installed active plugin, it will now be used like a template tag!

Well Done! and, here is the sample plugin: WPFirstAid Sample Widget (47). Enjoy!

This post was inspired by this comment at BuyNowShop.com, thank you @finid.