Add option to disable "Add new" button in relationship field

[1nfinite9]

Currently, the admin panel presents a button to add an item to a collection on the fly on a relationship field.

There could be use cases where a user should be only limited to just creating the current item and not add additional item to a relationship collection, so it would be nice to have an option to disable this button.

[jacobsfletch]

@1nfinite9 that button does not show if the user lacks create access. It sounds like you're looking for something very similar. Can you add some access control to your users?

[1nfinite9]

@jacobsfletch Apologies, I forgot to add that it would be nice to be able to do this without disabling it via access control. You'd still be able to create docs for that relationship individually, just not when editing or creating a doc that has a relationship to it.

[jacobsfletch]

@1nfinite9 totally, if we were to support this it would likely be a flag in somewhere in the config — something like relationships.create: boolean | function.

[1nfinite9]

@jacobsfletch Thanks! That's aligned with what I was looking for. Would the function be for providing custom actions to the button?

[jacobsfletch]

It would behave very similarly to the existing field-level conditional logic: https://payloadcms.com/docs/fields/overview#conditional-logic

We would need some API to set conditions on only parts of the field, as opposed to the whole thing.

[jacobsfletch]

@1nfinite9 I just opened a PR for this, check it out! #2070