How to add support for navigation menus to your WordPress theme
The new navigation menus system in WordPress 3.0 looks promising, but in my opinion it's not very usable yet. Anyway, here's one way to add navigation menus to your theme while maintaining backward compatibility:
In your theme's functions.php add something like the following code:
<?php
function mytheme_addmenus() {
register_nav_menus(
array(
'main_nav' => 'The Main Menu',
)
);
}
add_action( 'init', 'mytheme_addmenus' );
function mytheme_nav() {
if ( function_exists( 'wp_nav_menu' ) )
wp_nav_menu( 'menu=main_nav&container_class=pagemenu&fallback_cb=mytheme_nav_fallback' );
else
mytheme_nav_fallback();
}
function mytheme_nav_fallback() {
wp_page_menu( 'show_home=Start&menu_class=pagemenu' );
}
?>
In line 1 we add support for the navigation menus. The mytheme_nav() function is what you will use in the theme to display the menu. Inside that function we check if wp_nav_menu() exists, that means if we're running WordPress 3.0 (or later). If not we'll use the fallback function mytheme_nav_fallback().
Notice that the fallback also gets called if no navigation menus have been created in the admin area. That's what the fallback_cb parameter on line 4 does.To keep the HTM markup and the CSS consistent you'll have to use the container_class parameter on wp_nav_menu but the menu_class parameter for wp_page_menu.In your template use the following code to use your new custom function:
<?php mytheme_nav(); ?>
Resources
Ramblings
What's good about the new menu system:- Total control over what appears in the menu
- You can add posts, pages, categories and tags in the menu
- Very nice drag and drop interface
- You will have to teach your users how to use the system properly.
- If you create new pages they won't be added to your existing menu (except for top level pages).
- You can not control your page menus through the navigation menus interface. I think it is... very very odd that WordPress doesn't have a simple drag-and-drop interface to arrange pages.
- The previous point means that the new menu system is useless unless you update your theme.
- The
wp_nav_menu()call is inconsistent with the existingwp_page_menu()function.
Don't be to exited about the new menu system. It is is intentionally incomplete.
For example there is NO filter to filter the generated array of menus items. So, say goodbye to sub-menu and portions of menu display, you won't be able to do it with a powerful wordpress filter.
Why? Because the wordpress dev team has refused to include ONE more line of code and delayed it to WP 3.1.
Yeah. I'm really disappointed by the menu system. I've worked with it for maybe 30 minutes and found several flaws and omissions. The method I describe in the post is useful because users who want to use the nav menus can, but they don't have to.
Lox - I believe the developers addressed that isssue in 3.0.
Yeah, I think this is the relevant <a href="http://core.trac.wordpress.org/changeset/15256" rel="nofollow">last minute changeset</a>.
It's not like somebody is intentionally trying to make the nav menu system imperfect ;-)
How can we get the menu array or object to customize it the way we want. like we could do get_pages() to get pages is there any function like get_nav_menu().??
<code>wp_nav_menu()</code> can return instead of printing. If you'd rather get some data structures, a quick look at the <a href="http://xref.yoast.com/trunk/nav.html?_functions/wp_nav_menu.html" rel="nofollow">source</a> seems to indicate that one of the <code>wp_get_nav_menu*()</code> could do what you want.
add_theme_support( 'nav-menus' );
has changed to
add_theme_support( 'menus' );
Thanks John! Looks like this has changed before the 3.0 release. I updated the article. nav-menus still works but it apparently has been removed from the docs.
Do you have links to a better description of add_theme_support () -- i.e. information about where this actually is useful?
Can we add our own functionality in here? For example, could a plugin define something and then check to see if the theme supports it?
Also, using register_nav_menu () or register_nav_menus () call add_theme_support ('menu') internally.
The only docs I'm aware of are http://codex.wordpress.org/Function_Reference/add_theme_support and the source of course http://phpxref.ftwr.co.uk/wordpress/nav.html?_functions/add_theme_support.html
Looks like it's flexbile at first glance.
Thanks for the register_nav_menu() hint!
hi, very promessing! especially since i'm planning to call anchors with submenu items (which works in ten twenty).
to get it into my theme didn't work yet. i included what you say goes into the functions.php, after that the menu system shows up, but doesn't work, what i create doesn't show up, only the regular pages...?
what did i forget?
thank you
holger
i solved the problem: put this
at place for menu
Hrm. Sorry about this, but WordPress isn't smart enough to encode tags in comments etc, it just deletes all of that silently :-(
I'll look into fixing that.
This is highly annoying. WordPress doesn't simply hide tags it doesn't like, it deletes them from the database as well. No way to recover your comment.
Anyway, it should be fixed now <?php phpinfo(); // sue me ?>
thank you for your quick reply!
here again the code at pastepin:
http://wordpress.pastebin.com/eyuRMJYH
Ah, I see. I have updated the article, your pastebin doesn't use the custom function that I created for backward compatibility, but it will work if you don't need that.
Thanks Nicolas.
It worked great for me ... "straight out of the tin" and just what I was looking for. I was able to add a 2nd menu to the theme I was using in moments! I really appreciate the info!
Ian
That's great Ian! I'm glad I could help.
Why won't it work to simply have the wp_page_menu call after the else rather than a new function? I gave it a try and it doesn't work. Can anyone shed light on this for me? Thanks...
How does it not work? Also, the fallback is explained in the post.
Oh, it is making the call to the fallback in the wp_nav_menu parameters. No problems with that then. The code works for me as it is. Was what I needed actually... thanks.
:-)
the first tutorial (of three) that worked... :)
Hello Dear
i read your blog, its really nice
i have a query and i know that you know the answer of this
i am using wp nav menu to show 6 navigation menu in header here
http:// showprojects.net/projects/csrc/
Now i want when user clicks on any item(post,page,category,tag) in sub menu then the left sidebar will show all the submenus of that parent.
My question is similar to this thread
http://wordpress.stackexchange.com/questions/2802/display-a-only-a-portion-of-the-menu-tree-using-wp-nav-menu
Explaination
Root Menu
Sub menu 1
Sub menu 2 (clicked)
My sidebar will show only child sub menus of clicked root menu
Sub menu 1
Sub menu 2 (clicked)
Waiting for your answer.
Thanks
Vaseem Ansari
Hello Vaseem,
If you need general wordpress support I'd recommend you check out http://wordpress.org/support/ or http://codex.wordpress.org/IRC
Do you have any ideas why my wp nav function will not accept parameters?
I don't think it has anything to do with your function because even if I add it directly to the header.php without worrying about backwards compatibility it doesn't like the arguments.
Have you heard of any such things happening?
Thank you
I'd guess that you haven't defined the nav menu in the admin properly and that wordpress falls back to listing pages.
One way to adjust so not have to list separate classes for container in wp_nav_menu and wp_page_menu is this:
<code>
function mytheme_fallback() {
$output = '<nav class="pagemenu">';
$output .= wp_page_menu('show_home=Start');
$output .= '</nav>';
echo $output;
}