Conditional value list in a portal?

[anachron]

I've searched / read all the previous posts I could find on this, but still can't get it together somehow. Here's what I want to do:

I have Table A, Youths. I have Table B, Hours Worked.

There is a simple relationship "Youth Hours" between Youths <--> Hours Worked, based on the YouthID (unique ID.)

In a layout based on Youths, I have a portal that displays "Youth Hours".

For each Hours Worked entry in that portal, I want to be able to drag down and select a Category (Onsite, off-site, home) and then, in the next drop down menu, have the appropriate sub-category show up. (Mapped out below for clarity)

If:

Category = Onsite

SubCategory choices should be, "Red, Blue, Green"

Category = Off-site

SubCategory choices should be, "Brown, Black, Orange"

Category = Home

SubCategory choices should be, "purple, pink"

So far I've tried using a calculated field in Hours Worked, with a Case ( ) statement that is supposed to yield the appropriate subcategory, with the value list based on that calculated field. This works fine on the master layout, but breaks when used inside my portal. It shows every value inside every portal row, no matter what Category is selected for that portal row.

I'm sure this is cake; can someone put me out of my misery with a few words of guidance, or perhaps an example file?

Thank you..

[SlimJim]

If the situation is as finite and fixed as you stated the following is probably as simple as any other method. Make a table Category with two fields category and subcategory. Make eight records in the Category table of the eight combinations of category, subcategory. Relate an occurrence of Category to Hours Worked via the category field. Now define your category value list as you have done with the three entries, or - better - as the values of the field category in the Category table, show all values; define a subcategory value list as values from the field subcategory in the Category table, show only related records via the Category relationship. In the portal set up the field tab order to go from category to subcategory.

[anachron]

Thanks for this tip.

For the record, the problem still occurred, that is, in a given portal row, ALL of the possible sub-values kept showing up rather than just the appropriate sub-values for that row, until I made a self-relation between the Categories table and itself, and then used that as the source of the field for the value list.