[ META] Add new interface for user selection of managed files

[daggerhart]

This relates to File entity and re-usable managed files system #1448

We need a view where users can find the media they need, select that media, and "submit" their selection. When submitted, the form returns the fid of the selected file to the caller.

This type of UI will be a fundamental aspect of any media library solution we create.

From one perspective, views bulk ops already provides much of the needed UI for this issue.

• Integrated with views
• Single-item selection with radios
• Multiple-item selection with checkboxes

But we don't exactly need to execute an operation on the selected items. It might take a bit of tinkering to get VBO to work perfectly for this need, but likely not impossible.

Thoughts / feedback?

[klonos]

@daggerhart can't we (re)use the view that provides /admin/content/files for this?

[klonos]

I must say that after the addition of the Image Library in Backdrop v1.15 back in Jan. 2020, I'm surprised that there aren't any request for this.

I have started a thread in Zulip to gauge the desire/need for this: https://backdrop.zulipchat.com/#narrow/stream/218635-Backdrop/topic/File.20Library.2FBrowser

[argiepiano]

For reference, I adapted the functionality of the image browser to browser/pick managed files. This is documented here: https://forum.backdropcms.org/forum/implementing-custom-file-browserpicker

[klonos]

Thanks for sharing that @argiepiano! 🙏🏼

[klonos]

...inspired by @argiepiano's forum post, I filed #6512 as a starting point to getting this done based on Views and the existing implementation of the Image Library in Backdrop core (see #3297).

That would be the first baby step of what I envision to eventually become a very lightweight/opinionated, views-based equivalent of the functionality offered by https://www.drupal.org/project/file_browser and https://www.drupal.org/project/entity_browser in Drupal. The Backdrop implementation of this would more or less be the following:

• You can use Views to create "file browsers" (which is basically nothing more then a new special type of view displays - see #6512)
• We provide 2 default such file browser views/displays OOTB (one for images, and one for files), and we make them the default method for selecting files/images (see next points).
• We rename the default "Image" and "File" widgets for image and file fields to "Image library" and "File browser" respectively (just their human-readable labels - machine names remain the same, for backwards compatibility).
• We add an option in these widgets, which allows people to select any of the available view displays of type "file browser" that are available in the site.
• Perhaps provide a simple UI to manage the file- and image-specific settings for this type of views displays (to make it less "scary" than having to edit all the options provided by the Views UI - advanced users will still know that these are basically nothing more than views, and would be free to edit them directly via the Views UI if they want).