How to hide a Drop-down (Choice list) when it's empty?

[youming2007]

Hi ALL,

I have 2 drop-downs with a parent-child relationship:

  - Drop-down 1 is parent

  - Drop-down 2 is child (depends on Drop-down 1)

When parent's value is changed, child's values are populated automatically using Dictionary configuration (not Client Script).

Question 1:

  For example:

    Drop-down 1 has values: A, B and C

    When drop-down 1's value is set as A, drop-down 2 is populated with: -- None --, X and Y

    When drop-down 1's value is set as B, drop-down 2 is populated with: -- None -- and Z

    When drop-down 1's value is set as C, drop-down 2 is populated with: -- None -- only (NO value is set)

  When child is empty (only with -- None -- value), I want to hide child drop-down. Otherwise, I want to show it. Any ideas guys?

Question 2:

  When using both Dictionary configuration and Client script (Type = onChange) on the same drop-down, the execution order is Client script > Dictionary configuration.

  For example:

    Drop-down 1 has values: A, B and C

    When drop-down 1's value is set as A, drop-down 2 is populated with:

      - X, Y, Z by Dictionary configuration

      - X', Y', Z' by Client script

    => Client script is executed first, then Dictionary configuration. As a result, Drop-down 2 is populated with X, Y, Z

Can I switch or control the order of this behavior. I want Dictionary configuration is executed first, then Client script. Is it possible?

Many thanks,

[Archana Reddy2]

The above script works for this. Have you tried it modifying the field names?

[Archana Reddy2]

Ok, let me make it more clear.

Is this how you configured choices of child choice field in dictionary? If yes, modify the field names and labels and give a try with the above client script. It should work.

Otherwise, just share the screenshots of your dictionary and script that you have tried with. This helps.

Thanks

[youming2007]

Hi archanareddy,

I understood your script. Here is my screenshot:

  Parent: Category (Value = -- None --, A and B)

  Child: [Criterion 1]

    - Value = -- None --, X and Y when parent = A

    - Value = -- None -- when parent = B

In both case, -- None -- is selected. So, based on your script, child is always hidden

However, I realized that onChange() on Child is called after Child is populated. It's what I'm looking for. Instead of checking newValue == '', I used control.options.length to determine if the control has only -- None -- value (length = 1).

Anyway, thanks for your help.

Thanks,

[Archana Reddy2]

Client script will also work if you know which options of Parent field makes Child field options to only None. 

Anyways, glad you figured it out.