Constrain child picklist based on parent picklist

Question

I have a Case object which has 'Category' picklist with values 'Plumbing','Electrical' etc to handle the issue customer is reporting. Need to have a child object 'Parts' and it needs a Parts Picklist with values 'Pipe' ,'Elbow joint' , 'Switch','Wire'. We need the 'Parts' picklist on child object to show only the relevant values based on selection of 'Category' at case level. Is this possible at all using configuration or will this need a Lightning component ?

Tried workflows, flows to stamp the parent value on the child record but it simply doesn't constrain the child picklist while the record is being created first time. Subsequent edits do respect the constraint.

Any advice on how to proceed ?

Thanks.

Answer 1

Have you tried a solution mentioned at https://trailblazers.salesforce.com/answers?id=9063A000000tJbIQAU

So if the controlling picklist is on the Parent object with values "A,B,C" and the dependent picklist is on the Child object with values associated to "A,B.C", you can re-create the parent controlling picklist "A,B,C" on the Child object and re-create the picklist dependency on the child object too. The workflow, on updating the parent object controlling picklist, will update the Child controlling pickklist, which has the same values, and then the dependency is done.

Answer 2

Assuming these are single select picklists, one other option is to use different record types on the parts object.

You can control which picklists values are visible for the record type.

When you create the child record from the case, you would need to pre select the record type appropriately. That could get interesting, I could url hack my way through it in classic, but would need to think about how to make it nice for lex.