Apply styles to Layout Builder layout regions

+1

Per #3353493-12: Add ui_styles_page sub module → . On the long term ui_styles_layout_builder will go into:
- ui_styles_block for the block part
- ui_styles_layout for the layout part (section and regions)

Problem: there is currently nothing to alter all layout plugins automatically. This problematic is common for all plugins implementing PluginFormInterface.

I found out 📌 Introduce hook_plugin_subform_alter() for use with PluginFormInterface Needs work , which seems to be exactly what is needed to alter the configuration form automatically anywhere the plugin is used.

I think, this would be useful for ui_styles_block too, to avoid using a hook_form_alter, and so be generic between block layout and Layout Builder.

So we can either:
- wait for the Core issue to be merged, then implement a generic solution.
- delay ui_styles_layout creation (and ui_styles_layout_builder_deprecations) and manage the regions inside ui_styles_layout_builder for the moment.

I also imagined a solution to alter layout plugins which use the LayoutOptions class form the Layout Options module, by providing a layout class which extends Layout Options class, but not generic at all.

After discussion with @pdureau, 2 days ago.

Ok to currently do it in ui_styles_layout_builder until Core provides a generic alteration mechanism.

I wonder if on the long term it would not be better to provide a new LayoutOptions plugin for the styles.

But as we may have also discussed to go full UI Patterns even for layouts, then it should be a UI Patterns Settings plugin...

So currently sticking to the same logic of only adding parts in the form.

I tried to use hook_preprocess_layout but the problem is that in this hook there is the layout settings, the layout plugin definition but not the layout plugin instance. So not possible to access third party settings.

I wonder if UI Styles data should then be stored inside the settings???

(I wanted to target something generic in preparation of refactoring, to avoid the hook_entity_view_alter())

I will rework the form and configuration structure at the same time.

Otherwise it will require adaptations in gin_lb.

Finally, currently no config storage reorganisation.

Automatically closed - issue fixed for 2 weeks with no activity.