Add filter in WP_Nav_Menu_Widget

[cyman]

There is currently no way to change the arguments of function wp_nav_menu( array( 'fallback_cb' => '', 'menu' => $nav_menu ) ); in file wp-includes/default-widgets.php for class WP_Nav_Menu_Widget as there is no hook applied to the argument.

Suggested solution:

wp_nav_menu( apply_filters( 'nav_menu_widget_args', array( 
  'fallback_cb' => '', 
  'menu' => $nav_menu 
) ) );

[cyman]

I am sure I could create a patch for this (I am theme and plugin developer), but it will be first time for me, so I will appreciate instructions/link how to do that.

[johnbillion]

Thanks for the report cyman.

The wp_nav_menu() function contains a filter which gets applied to the arguments for all nav menus (​see here).

$args = apply_filters ( 'wp_nav_menu_args', array $args );

Is this filter sufficient for your use case? You can target the menu using the menu parameter. Eg:

add_filter( 'wp_nav_menu_args', function( array $args ) {
    if ( 'my_menu' == $args['menu'] ) {
        // do something
    }
} );

If this isn't sufficient, and you think we might need a more targeted filter for the WP_Nav_Menu_Widget, then you can read up about Subversion and creating a patch on ​the SVN page of the WordPress handbook. Once you've created a patch file you can upload it to this ticket.

[cyman]

Thank you for a quick answer @johnbillion!

Yes, I am aware of the wp_nav_menu_args filter and how to target specific menus with if clauses.

However, this feels to me more a hack than elegant solution, especially in some cases (and I found other questioning the ​same thing elsewhere) when one'd like a specific menu classes or walker applied to all custom menus that appear in the sidebars.

Example usecase: I use the Tw Bootstrap for creating the theme, so I would like to apply the ​Bootstrap Navwalker and some Bootstrap classes to all the sidebar menus. While I don't want to use the navwalker for the custom menu positions in my theme (for example main navigation in header and footer navigation).

What I have to do now to achieve that is to register a new widget (which extends the WP_Nav_Menu_Widget) and define new widget method just to change the arguments of the wp_nav_menu function call. And then use unregister_widget to unregister default menu widget.

It would be much easier to add a filter in a theme to change these arguments for the existing custom menu widget. That would also be more consistent how other widgets/functions in the file default-widgets.php have hooks applied, for example the WP_Widget_Pages:

wp_list_pages( apply_filters( 'widget_pages_args', array(
	'title_li'    => '',
	'echo'        => 0,
	'sort_column' => $sortby,
	'exclude'     => $exclude
) ) );

I hope I explained my point.

I'll take a look at the SVN instructions (I use git daily, so I hope I don't have troubles) you linked to and create a patch file.

[johnbillion]

Replying to cyman:

I'll take a look at the SVN instructions (I use git daily, so I hope I don't have troubles) you linked to and create a patch file.

In that case, you can ​use Git to create an svn-compatible patch to make things easier for yourself.

[johnbillion]

Related: #22364

[cyman]

I attached the patch file per ​these instructions.

Fingers crossed I did everything right :)

[SergeyBiryukov]

The filter needs to be documented as per the ​documentation standards.

[cyman]

Replying to SergeyBiryukov:

The filter needs to be documented as per the ​documentation standards.

I will handle the docs this week, ok?

[SergeyBiryukov]

Sure.

[cyman]

Added the inline documentation.

[cyman]

Online docs added, what's the next step? (fyi: I am contributing to the core for the first time.)

[DrewAPicture]

Hi Cyman,

Thanks a lot for adding the hook documentation.

It occurs to me that instead of introducing a new filter here -- which would effectively be a duplicate of wp_nav_menu_args -- perhaps we should simply introduce a "context" parameter to the existing filter hook that would allow targeting of this particular context. Maybe something like 'menu-widget' (this context), vs 'none' or (main context).

[cyman]

Replying to DrewAPicture:

It occurs to me that instead of introducing a new filter here -- which would effectively be a duplicate of wp_nav_menu_args -- perhaps we should simply introduce a "context" parameter to the existing filter hook that would allow targeting of this particular context. Maybe something like 'menu-widget' (this context), vs 'none' or (main context).

I would not agree, all the other native WP widgets have the filters applied. This was the only exception in default-widgets.php.

While adding a context to the existing filter sounds like a great idea, I think that we should then also consider doing the same for the other native WP widgets in the default-widgets.php file - keeping the code consistent, right?

[DrewAPicture]

Replying to cyman:

While adding a context to the existing filter sounds like a great idea, I think that we should then also consider doing the same for the other native WP widgets in the default-widgets.php file - keeping the code consistent, right?

You were correct the first time. I think adding a completely new filter here falls more in-line with core conventions for widgets.

In 29463.diff​ I've broken the args array out to a separate variable for readability, as well as passed the $nav_menu object and $args array containing display arguments for the current widget. Access to $nav_menu and $args should make targeting specific widgets, menus, and sidebars much simpler.

[johnbillion]

This should go in but it's a bit late for 4.1.

[iseulde]

has-patch 4.2-early so moving to 4.2.

[MikeHansenMe]

Patch still applies.

[DrewAPicture]

29463.2.diff​ fixes a couple of things missing in 29463.diff. Good to go.

[SergeyBiryukov]

In 31325:

Add 'widget_nav_menu_args' filter for Custom Menu widget arguments.

props cyman, DrewAPicture.
fixes #29463.

[cadic]

#15550 was marked as a duplicate.