[wp-trac] [WordPress Trac] #18623: Allow themes to pre-register multiple custom backgrounds

[WordPress Trac]

#18623: Allow themes to pre-register multiple custom backgrounds
--------------------------------------+-----------------------------
 Reporter:  zamoose                   |       Owner:
     Type:  feature request           |      Status:  new
 Priority:  normal                    |   Milestone:  Future Release
Component:  Customize                 |     Version:  3.3
 Severity:  minor                     |  Resolution:
 Keywords:  dev-feedback needs-patch  |     Focuses:
--------------------------------------+-----------------------------

Comment (by celloexpressions):

 The `theme.php` part of obenland's latest patch [attachment:18623.4.diff]
 should theoretically still work, so there's a basis for the internal bits
 there (and it's based on headers, per above).

 The path to feature parity between headers and backgrounds, in terms of
 the images UI, goes through #36581 at least philosophically. Alternatively
 if we don't want to include the cropping part, we could build whatever
 would be needed to support this in UI directly in
 `WP_Customize_Background_Image_Control`, although I would definitely
 prefer an implementation that is reusable via the API and generic core
 controls. As most of the headers code in the customizer is obsolete
 (predating JS-templated controls), we should not use it directly.

 I would suggest that anyone interested in improving background images have
 a higher-level discussion somewhere (perhaps Slack) to evaluate whether we
 do want to strive for feature parity with header images, and also figuring
 out how to approach the cropping and `background-size` property situation
 (see related tickets). That would better inform the approach that would
 work the best here. Also need a decision on whether the old custom
 background screen (only available for no-JS users now) should still be
 updated.

--
Ticket URL: <https://core.trac.wordpress.org/ticket/18623#comment:34>
WordPress Trac <https://core.trac.wordpress.org/>
WordPress publishing platform