Sortable relation_select field instances and endpoints

Jorrit,

Are you talking about making sortable the instances of a Relation Select field on an entity edit page?

-Steve

If a relation field accepts multiple relations, those 'instances' are what I'm referring to, which I think need to be sortable.

Wouldn't "metadata to be specified for a relation" be actual fields on the relation(s)? See #1645534: Add entity fields to relation select field widget.

And would the field instance delta (int) be enough for your needs?

OK, so we're at the same place then. Let's make this happen.

I think theme_menu_overview_form will be a helpful example to help us implement Drupal's tabledrag.

Regarding the two things that could be sorted:

1. Relation Select field instances.
2. Relation Select relation endpoints.

You can see both pointed out by the blue brackets in this image. The red rectangles are relation fields.

Does this make sense? If so, which are you referring to: (1), (2), or both? I'm thinking both.

After re-reading everything I see that you are talking about (1), field instances, and are ignoring the use case of (2), endpoints. While one can easily sort more than one Relation Select endpoint by removing and re-adding endpoints in order, It seems reasonable to support endpoint as well as instance ordering as drupal_add_tabledrag() or similar might work for both. I haven't implemented tabledrag or any of this sorting before. Do you have any ideas or experience with this?

Jorrit, are you using any core UI such as tabledrag or similar?

Jorrit,

I've had only a small chance to check out your patch. I have a few notes. First:

One thing that keeps confusing me is why we need an additional 'weight' field on the relation entity. Why can't we just use field delta?

I think you are working on a use case that I don't quite grok. In what you seem to be accomplishing here, it appears that you want to essentially adjust the weights of relation field instances relative to the entity on which they are attached (i.e delta) ....AND you want these weights to be relevant in the global context of your site. In other words: It seems you are trying to manage your relations as they are referenced as instances of Relation Select fields at the same time that you are trying to manage your relations among themselves (globally -- hence, field delta does not help you)...

Relation Select field instances are not the same as relations.

Relation Select field instances create and reference relations.

Each relation instance has two contexts:

1. On its own -- it relates endpoints and has fields. It is identified by a relation id.
2. On an endpoint -- the current entity is an endpoint. The relation instance connects this entity with other endpoints.

Each Relation Select field instance has one context:

1. On an endpoint -- the current entity is an endpoint. The field instance may be one of many, in which case, as a field instance, it has a delta.

What you are wanting to do is provide an integer that functions as both the delta to each relation field instance AND a value that can (supposedly) be useful in the context outside of an endpoint(s).

Is this the understanding I should have of what you want to accomplish?

OK, Jorrit, I know we've had different use cases around this issue, but I'm going to go ahead with implementing sortable endpoints and instances *without* the weight field -- just using field delta. I know from our conversations that you're working on a separate module to do what you want to do. We'll see how it goes. Here's a patch that I know doesn't work, but starts down the path.

TODOs I can see at the moment:

1. Move sorting from instances to endpoints (that's most important to me at the moment).
2. Don't rely on weight field; use delta.
3. Support any arity
4. Rename widget or just integrate into stock RS widget.

NOTES on this patch:

1. 'theme callback' => 'ajax_base_page_theme', relation_select_field_is_empty() and a couple other things should be in other issues/patches.

So here's the patch...

Well I'll be damned, there *was* sortable endpoints, apparently. I noticed in https://vimeo.com/30394905 around 8:00m that endpoints seems to be sortable. Forget the above patch and let's get the old feature fixed. Tagging as a regression. Marking Bug.

The value for 'max arity' when set to 'infinity' was correctly set to '0' but the test for setting the item list as sortable was failing in that case since it was testing for >2.

Here's the same patch without the extra garbage.

and again

Cleaned up and committed to f91ec66. Thanks, trrroy.

It seems that we still can't order the relation.
I've create a relation between node with unlimited items, but I can't drag the item & change order.

Setting back to fixed since another issue exists that has a patch regarding sortable endpoints.: #1826538: Cannot sort endpoints before saving