I am working on a plugin, which creates a couple of Virtual pages, and I wish these links to be available in Menu admin page, to let users have the liberty to add them as they create menus.
I want to add a Meta box in Menu administration, very similar to Page/Category meta boxes, to let users select what page to add in their menu.
Apparently, the only possible research is in the core itself.
Here, /wp-includes/nav-menu.php, we can get how to insert the meta box:
add_action('admin_init', 'so_13875144_nav_menu_meta_box');
function so_13875144_nav_menu_meta_box() {
add_meta_box(
'my-custom-nav-box',
__('Custom Box'),
'so_13875144_display_menu_custom_box',
'nav-menus',
'side',
'default'
);
}
function so_13875144_display_menu_custom_box() {
/* Not sure about this global var */
//global $_nav_menu_placeholder;
//$_nav_menu_placeholder = ( 0 > $_nav_menu_placeholder ) ? intval($_nav_menu_placeholder) - 1 : -1;
?>
<p id="menu-item-custom-box">
<label class="howto" for="custom-menu-item-custom-box">
<span><?php _e('URL'); ?></span>
<input id="custom-menu-item-custom-box" name="menu-item[<?php echo $_nav_menu_placeholder; ?>][menu-item-custom-box]" type="text" class="code menu-item-textbox" value="my text" />
</label>
</p>
<?php
}
But, the hard part, which I haven't managed to make work, is to save the value.
This is the file /wp-admin/nav-menus.php that has to be studied.
Tried to hook into the action wp_update_nav_menu, but the custom meta box input field is not being passed into $_POST.
WordPress Answers may have some hint: https://wordpress.stackexchange.com/search?q=wp_update_nav_menu
I know I'm late to the party but just for anyone else trying to do this...
b__ is right, that is the way to get it to show on the page except it is much easier to use checkboxes than any other field because there is an inbuilt javascript function that looks for checkboxes.
All you need to do is copy the html from an existing checkbox -
<li><label class="menu-item-title"><input type="checkbox" class="menu-item-checkbox" name="menu-item[-1][menu-item-object-id]" value="2"> Sample Page</label><input type="hidden" class="menu-item-db-id" name="menu-item[-1][menu-item-db-id]" value="0"><input type="hidden" class="menu-item-object" name="menu-item[-1][menu-item-object]" value="page"><input type="hidden" class="menu-item-parent-id" name="menu-item[-1][menu-item-parent-id]" value="0"><input type="hidden" class="menu-item-type" name="menu-item[-1][menu-item-type]" value="post_type"><input type="hidden" class="menu-item-title" name="menu-item[-1][menu-item-title]" value="Sample Page"><input type="hidden" class="menu-item-url" name="menu-item[-1][menu-item-url]" value=""><input type="hidden" class="menu-item-target" name="menu-item[-1][menu-item-target]" value=""><input type="hidden" class="menu-item-attr_title" name="menu-item[-1][menu-item-attr_title]" value=""><input type="hidden" class="menu-item-classes" name="menu-item[-1][menu-item-classes]" value=""><input type="hidden" class="menu-item-xfn" name="menu-item[-1][menu-item-xfn]" value=""></li>
but give them each a unique ID and put your details in for the URL, title etc.
Then, add a submit button at the end to add to the menu -
<input type="submit" class="button-secondary submit-add-to-menu right" value="<?php esc_attr_e('Add to Menu'); ?>" name="YOUR NAME" id="YOUR ID" onclick="(function(){$('#THE DIV YOU HAVE PUT YOUR LIST IN').addSelectedToMenu( api.addMenuItemToBottom );})"/>
And that should add the item to the list.
This is a pretty old question but I was trying to do this today so in case it points anyone in the right direction...
I won't cover adding the meta box, as it's covered above. I'll also only cover a custom link as I haven't looked into adding a post, page, term link etc.
Just to cover the logic of how I got there...Looking at wp-admin/js/nav-menu.js, for a custom link you'll want to use window.wpNavMenu.addItemToMenu(). This ajax submits to the function wp_ajax_add_menu_item() in wp-admin/includes/ajax-actions.php. This then submits to wp_save_nav_menu_items() in wp-admin/includes/nav-menu.php. The upshot from looking at these files is that all menu items are of a post_type, taxonomy, post_type_archive or custom type.
Hook the javascript to the HTML as you wish, but if you want to submit a custom link, you need to call addItemToMenu() as follows:
var url = 'http://example.com';
var title = 'Link text';
window.wpNavMenu.addItemToMenu({
'-1': {
'menu-item-type': 'custom',
'menu-item-url': url,
'menu-item-title': title,
}
}, window.wpNavMenu.addMenuItemToBottom);
Menu item type has to be "custom" otherwise it requires info for a post, page etc. with which to associate the menu item.
