Approach for creating a dropdown for an entry's field based on a selected entry

Question

I'm running in to a situation that I don't know how to solve in Craft. I want admin CP users to select one entry from a list, and then based on that specific entry select a value from inside the selected entry from a dropdown.

We're using Craft to model a headless API through GraphQL and this dropdown selection affects business logic in my client application.

Research: looked at a few solutions, amongst which the https://plugins.craftcms.com/super-dropdown plugin. However, I couldn't find a way to capture the selected entry ID and fill the dropdown based on that value. So I don't think that's a way to solve this.

Basically what I would want to achieve.

1. User selects the entry they want to reference to
2. They select the desired field value from a conditional dropdown. The options are extracted from the selected entry.

Currently I've (sort of) solved the situation having the users type the value name in a separate text field. This is very fragile though, since a typo, change in value in the entry or even a space will not match it to the entered value in the original entry and break the functionality.

Graphic examples:

Answer 1

There's nothing in Craft core that will solve that use case, and I'm not aware of any plugins that would either.

To make your current workaround a little bit more resilient, I'd suggest converting whatever field containing the values that you want to use on the entries, into to an Entries (or Categories) field (i.e. that all possible values, such as "Week 2", are represented as entries, instead of just text). Then, make the "Observatiemoment" field into an Entries (or Categories) field as well, targeting the same source. This way, authors will be able to select the values via the element selection modal, instead of having to type them – which at least removes the risk of spelling errors (even if it won't be possible to also limit the choices to only values selected in the selected "Checklist" entry).