Smart forms: Dynamic, user-generated dropdown, instead of using domains or subtypes

[AlfredBaldenweck]

From this post

I'd like to be able to make text fields have a drop down dynamically, based on an arcade expression that the user defines themselves.

My use-case, given in the post linked above, is to grab values from a related record as an option.

So, if the relationship is something like:

Table 1	ORIG_ID	Field2
0	Paris
1	London
2	Madrid

Table 2	Fruit	RELID
0	Pomme	Paris
1	Poire	Paris
2	Citron	Paris
3	Apple	London
4	Pear	London
5	Manzana	Madrid

I'd like the dropdown for Field2 in the origin table to give me the options of Pomme, Poire, and Citron when I'm doing something in the record for Paris.

I specifically want to be able to do this using Arcade because my use case is actually more complicated: Parent Table has a 1:M relationship with Child1 and a 1:M relationship with Child2. I'd like to use values from Child1 in the dropdown of Child2.

Thanks!

[AlfredBaldenweck]

Looks like this user is trying to do something similar in Experience Builder: Edit field adding a code and display 3 differnt de... - Esri Community

[MarkusSchenardi]

This functionality is a must. Domains are not enough flexible to handle fast changing lookup-lists. 

Changes on domains require service interruptions and administrative permissions, which is an absolute no-go.

Use case 1:

1.  hold a list of material and cost in a table > changes rapidly
2. let the user create a new feature (e.g. a pipe) and select the material based on the table
3. calculate a cost estimation based on values of the table (price, diameter, extra costs etc).

Use case 2:

1. have a list of people (fast changing)
2. have an attribut to store for example a project manager based on the table