So, today’s post will explore something you’ve seen as a user ever time you login to WordPress: the admin navigation on the left hand side of your screen. As a developer, I often want to give you (the user) access to some configuration options related to the plugin, feature, or page that I’m working on. Well, as you might expect, WordPress has a couple of functions and hooks to help us add a custom menu item to your admin navigation. Here’s how it works:

Adding a new admin section

First we will add a function which will write our custom page

function dinkum_page() {
	// Check if the user has enough rights.
	if (!current_user_can('manage_options'))  {
		wp_die( __('You don\'t have permissions to access this page.') );
	}
 
	// Write our custom html
	echo '<h2> Hello there!</h2>';
	echo '<div class="wrap">';
	echo 'We can put our custom form here or any content we need!! ';
	echo '</div>';
}

Then, we need a function to add our menu options. Here it is:

function dinkum_menu() {
	add_menu_page( 'Dinkum', 'Dinkum', 'manage_options', 'dinkum-section', 'dinkum_page' );
}

And finally we have to use the magic WordPress tool: the action hook!

add_action('admin_menu', 'dinkum_menu');

Here is the result:

Taking this concept a step further is the ability to add some items to our new “Dinkum” section? Easy! We can use the add_submenu_page function.

function dinkum_menu() {
 
	add_menu_page( 'Dinkum', 'Dinkum', 'manage_options', 'dinkum-section', 'dinkum_page' );
	add_submenu_page( 'dinkum-section', 'Setting', 'Setting', 'manage_options', 'dinkum-section-setting', 'dinkum_page');
}

And finally, in the recently WordPress 3.1, we have a new admin bar. Did you know it? You need to be logged to see it, of course.

Now its time to add some code. We attach our function to the admin_bar_menu hook

add_action('admin_bar_menu', 'dinkum_adminbar_menu');

Add the options

function dinkum_adminbar_menu(){
	global $wp_admin_bar;
	$wp_admin_bar->add_menu(
		array(	'id' => 'dinkum-menu',
				'title' => __( 'Dinkum' ),
				'href' => get_admin_url(null, 'admin.php?page=dinkum-section')
		)
	);
 
	$wp_admin_bar->add_menu(
		array(	'parent' =>'dinkum-menu',
				'id' => 'dinkum-menu-setting',
				'title' => __( 'Setting' ),
				'href' => get_admin_url(null, 'admin.php?page=dinkum-section-setting')
		)
	);
 
}

And here is the result. Quite nice, right? :)

If you want to read more about menus, take a look here

And you can download the files here

Emiliano Jankowski is Senior Developer at Dinkum Interactive, specializing in creating elegant solutions to complex problems. Emiliano also leads Dinkum’s internal technology development projects, leveraging expertise with WordPress and CodeIgniter despite ten years experience in ASP and .NET. Emiliano is an avid scuba diver and lives in both Barcelona and Buenos Aires.

What does WordPress say?

“Hooks are provided by WordPress to allow your plugin to ‘hook into’ the rest of WordPress; that is, to call functions in your plugin at specific times, and thereby set your plugin in motion.”

So, basically hooks, will let you modify content, add features, and much more, without touching anything of the WordPress Core.

There are two types of hooks:

• Actions: This kind of hooks are launched by the WordPress Core at specifics points during execution, or when specific events occur. Like publishing a post, changing themes and so on.
• Filters: They will let you to modify content on the fly. You can, for instance, modify a post content before it is shown to the user or just doing the opposite like modifying some user content before saving it to the database.

Let see some examples to truly understand the magic of hooks!

Filter hooks

function set_default_content($content) {
        $default_post_content = "This is our default post text!!";
        if (!isset($content) || trim($content)=='')
                return $default_post_content;
 
        return $content;}
 
add_filter("the_content", "set_default_content");

function change_title_color() {
	echo '
<!--
                    #site-title a {
                            color: #08FF00; /* lovely green :) */
                    }
-->
 
';
}

add_action('wp_head', 'change_title_color');

 remove_filter('filter_hook','filter_function') 
 
remove_action('action_hook','action_function')

Emiliano Jankowski is Senior Developer at Dinkum Interactive, specializing in creating elegant solutions to complex problems. Emiliano also leads Dinkum’s internal technology development projects, leveraging expertise with WordPress and CodeIgniter despite ten years experience in ASP and .NET. Emiliano is an avid scuba diver and lives in both Barcelona and Buenos Aires.

Since Dinkum Interactive is a big WordPress fan and uses the platform itself, I took a few moments to take Scribe for a test drive in this SEO tool review and here’s what I found:

Overall, I think that it’s a good tool especially for those with less experience. This was the  first time I’ve ever used this WordPress plug-in; when I selected pressed the “Analysis” button I had no idea of what to expect.  My initial score was a 78% and after a few tweaks I was able to bump it up to 100%.

I think Scribe is particularly useful for those learning Search Engine Optimization (SEO) techniques and can be a good reminder for those of us that already have experience. With that said, I think that it might be a worthwhile investment to keep yourself honest while learning; it may not be a must have indefinitely.

What did you think about Scribe (be kind…)? Would it be helpful to you? Would you use it?

Bill Rowland