No way to filter wp_terms_checklist() to prevent checked taxonomies jumping to the top

[husobj]

I frequently use categories and custom taxonomies.

By default when editing a post, any selected categories or hierarchical terms with jump to the top of the list.

I understand that in many scenarios this provides a better ui experience, but when you have a hierarchical taxonomy with multiple nested levels, it is actually a worse experience as the category jumps out of context and you cannot easily identify it's parent category.

This is particularly frustrating if you have subcategories with similar or the same name as another category - the often happens in ecommerce applications etc.

I'm not prosing that the default behaviour is change, but it would be nice to be able to filter the output at some point, probably in the wp_terms_checklist() function or Walker, to prevent selected categories jumping to the top.

[solarissmoke]

#10982

[nacin]

Re-opening. I agree a filter would be good here. #10982 and #3130 advocate a change in default behavior, this advocates a filter.

[husobj]

Nacin, Thanks for reopening.
I think a filter is definitely appropriate for this rather than saying "it must work like this" as there are defintely a few cases when you may want to override.

Scribu, thanks for the patch.
I think it should also pass the $taxonomy so you could choose to only do this for certain taxonomies.

[aaroncampbell]

I'm all for the filter. For flatter taxonomy structures or ones where parent category isn't important, floating to the top is fine.

[nacin]

For some reason, it feels like this filter isn't in the most appropriate place. This is modifying the behavior of a template function every time it fires, rather than at the point of where arguments are passed in to it, where it is called. Am I making sense?

[scribu]

Well, the alternative would be to filter all the arguments in the metabox handler, before calling wp_terms_checklist().

[husobj]

The wp_terms_checklist() function is called in the following places where you would probably want to be able to influence the output:

post_categories_meta_box()
wp_category_checklist();
_wp_ajax_add_hierarchical_term() - in ajax-actions.php
inline_edit() - in class-wp-posts-list-table.php

[scribu]

Besides wp_category_checklist(), all of the other areas are hard to access, hence the filter placement.

I was mostly focused on post_categories_meta_box().

[nacin]

Okay. Would it make sense to then place a filter around the entire passed in $args?

[husobj]

I suppose you could do. I can't really see that you'd want to filter the other $args but maybe it makes sense to provide that option.

For example, I suppose you could filter the $args['selected_cats'] value it you wanted to always check certain terms in certain situations, perhaps?

And I suppose the option of overriding the Walker could be quite fun too?

[husobj]

Something like 20054.3.patch?

[SergeyBiryukov]

Replying to husobj:

For example, I suppose you could filter the $args['selected_cats'] value it you wanted to always check certain terms in certain situations, perhaps?

Being able to set some default categories for a new post would probably make sense.

[nacin]

In [20710]:

Add a filter to wp_terms_checklist() that wraps the function's arguments.

Mainly designed to allow checked_ontop to be turned off.

props husobj.
fixes #20054.

[scribu]

Well, that simplified things a bit:

​https://github.com/scribu/wp-category-checklist-tree/commit/d1c3c1f449e1144542efa17dde84a9f52ade1739

[husobj]

Replying to scribu:

Well, that simplified things a bit:

​https://github.com/scribu/wp-category-checklist-tree/commit/d1c3c1f449e1144542efa17dde84a9f52ade1739

Just a bit! :)

[guar]

It works, but I feel it might have been simpler if I could have set these arguments as part of the register_taxonomy() function.

As it is I have to add conditionals to a filter to choose which taxonomy this filter is applied to (assuming I want to set this on a taxonomy by taxonomy basis rather than all).

I'd be happy to submit a patch if others think this is a good alternative method.

[SergeyBiryukov]

Replying to guar:

It works, but I feel it might have been simpler if I could have set these arguments as part of the register_taxonomy() function.

Feel free to create a new ticket with that suggestion.

[aaroncampbell]

Honestly I don't see the need. The checks wouldn't be very expensive since the taxonomy is passed in the args.

However, this ticket was closed as fixed seven months ago. If you want to try to get traction for the change you should open a new ticket.

[husobj]

Replying to guar:

It works, but I feel it might have been simpler if I could have set these arguments as part of the register_taxonomy() function.

I guess that would be useful too, but the benefit of the filter is that it can be used to affect existing instances of register_taxonomy() in the WordPress admin and plugins, without having to hack and change the register_taxonomy() args.