Integrate meta box support for the new editor

[desrosj]

Meta box functionality for the new editor exists in gutenberg/lib/meta-box-partial-page.php. This should exist in WordPress Core.

[andizer]

I have one question about the approach. Do you want this as a class to contain all functionality? Or should it be done the same way it has been done in gutenberg/lib/meta-box-partial-page.php?

[youknowriad]

Just a notice that we're doing small tweaks in this PR ​https://github.com/WordPress/gutenberg/pull/10676
In case anyone already started doing a patch.

[pento]

45112.diff​ is a first pass at adding meta box support. It needs unit tests added, and testing in conjunction with the patch on #45037.

[ocean90]

45112.2.diff​ includes ​https://github.com/WordPress/gutenberg/pull/10850.

[pento]

In 43778:

Block Editor: Add helper functions to collect meta box information.

To allow the block editor to render meta boxes, it needs to collect information about how those meta boxes are registered, and format it for the block editor to make use of.

See #45112.

[pento]

In 43779:

Meta Boxes: Add __back_compat_meta_box and __block_editor_compatible_meta_box flags to meta boxes.

When meta boxes are registered, they can use the __back_compat_meta_box and __block_editor_compatible_meta_box flags, to show whether this registration just exists for if the classic editor is loaded, and whether this meta box is compatible with the block editor.

When a meta box marks itself as incompatible with the block editor, and WP_DEBUG is enabled, a warning will show inside that meta box in the classic editor.

As all core meta boxes have been recreated in the block editor, they can be marked with the __back_compat_meta_box flag.

See #45112.

[pento]

Meta box support has been ported.

[ocean90]

@pento Was there a reason for not using 45112.2.diff​?

[pento]

Only that I missed that you'd added the patch, sorry about that. 🙂

[ocean90]

In 43792:

Meta Boxes: Sync checks for valid meta boxes from do_meta_boxes() to the_block_editor_meta_boxes().

See #45112.

[afercia]

While the notice appears only when define( 'WP_DEBUG', true ), ideally it shouldn't appear at all for meta boxes widgets exclusively meant to be used in the Dashboard. Right now, any dashboard widget added by plugins gets the notice:

[afercia]

For completeness, in the Gutenberg screen:

[TimothyBlynJacobs]

Adding to this, I think it should really only run on post type screens as opposed to whitelisting the dashboard. I know I've used the meta box API for completely custom admin pages, I'm sure others have as well.

[nerrad]

Replying to TimothyBlynJacobs:

Adding to this, I think it should really only run on post type screens as opposed to whitelisting the dashboard. I know I've used the meta box API for completely custom admin pages, I'm sure others have as well.

+1 to this. We also use the metabox API on custom admin pages.

[zodiac1978]

#45173 was marked as a duplicate.

[Nikschavan]

In the 5.0 beta.1, the meta boxes registered from the theme are not displayed, It works correctly when Gutenberg plugin is activated.

To reproduce

1. install WP 5.0 beta.1 on a fresh site and install any theme that registers a meta box (example - Astra)

The meta box will not be displayed in the block editor.

2. Install and activate Gutenberg from the plugin repository and the meta boxes will be displayed now.

[Nikschavan]

Upon some debugging it seems action do_action( 'add_meta_boxes', $post_type, $post ); is not fired inside the block editor.

Whe gutenberg is activated it gets fired from gutenberg_collect_meta_box_data() - ​https://github.com/WordPress/gutenberg/blob/master/lib/register.php#L172

[zodiac1978]

Related #45172

[Nikschavan]

45112.3.diff​ fires the action add_meta_boxes before the the_block_editor_meta_boxes() is called in /src/wp-admin/edit-form-blocks.php.

[DrewAPicture]

Looks like [43779] introduced a problem with static meta box display callbacks expressed as 'Class::method'. Patch on #45192 should take care of it.

[swissspidy]

#45195 was marked as a duplicate.

[swissspidy]

#45200 was marked as a duplicate.

[jeherve]

The error message appears to be triggered on dashboard widgets as well, as reported above and here:

• ​https://github.com/WordPress/gutenberg/issues/11058

[43830] does not solve the problem.

Since wp_add_dashboard_widget uses add_meta_box here, should __block_editor_compatible_meta_box be set to false in that meta box's $callback_args to solve the issue for all dashboard widgets? I don't believe any dashboard widget is meant to support the block editor yet.

[ocean90]

Without Gutenberg activated, I'm seeing all the default meta boxes in the Advanced Panels section, see advanced-panels.png​. Can someone confirm?

[websupporter]

Without Gutenberg activated, I'm seeing all the default meta boxes in the Advanced Panels section, see advanced-panels.png​. Can someone confirm?

I can reproduce it with the current beta2.

[noisysocks]

Replying to ocean90:

Without Gutenberg activated, I'm seeing all the default meta boxes in the Advanced Panels section, see advanced-panels.png​. Can someone confirm?

Yes, that looks like a bug. I've created #45249 to track it. Thanks!

[jeherve]

Replying to jeherve:

The error message appears to be triggered on dashboard widgets as well, as reported above and here:

• ​https://github.com/WordPress/gutenberg/issues/11058

[43830] does not solve the problem.

Since wp_add_dashboard_widget uses add_meta_box here, should __block_editor_compatible_meta_box be set to false in that meta box's $callback_args to solve the issue for all dashboard widgets? I don't believe any dashboard widget is meant to support the block editor yet.

To close the loop, it seems that this was fixed in [43856].

[pento]

In 44131:

Block Editor: Add helper functions to collect meta box information.

To allow the block editor to render meta boxes, it needs to collect information about how those meta boxes are registered, and format it for the block editor to make use of.

Merges [43778] from the 5.0 branch to trunk.

See #45112.

[pento]

In 44132:

Meta Boxes: Add __back_compat_meta_box and __block_editor_compatible_meta_box flags to meta boxes.

When meta boxes are registered, they can use the __back_compat_meta_box and __block_editor_compatible_meta_box flags, to show whether this registration just exists for if the classic editor is loaded, and whether this meta box is compatible with the block editor.

When a meta box marks itself as incompatible with the block editor, and WP_DEBUG is enabled, a warning will show inside that meta box in the classic editor.

As all core meta boxes have been recreated in the block editor, they can be marked with the __back_compat_meta_box flag.

Merges [43779] from the 5.0 branch to trunk.

See #45112.

[jeremyfelt]

In 44141:

Meta Boxes: Sync checks for valid meta boxes from do_meta_boxes() to the_block_editor_meta_boxes().

Merges [43792] from the 5.0 branch to trunk.

Props ocean90.
See #45112.