CustomField And ScriptRunner Behaviours

[Gebremeskel Ambasager Tetemke]

I have two customfields: X and Y. The fields are dependent to each other; when X is populated with invalid data, Y becomes required field and X will be hidden. The same is true for X. When Y is  populated with invalid data, X becomes required field. If both are populated with invalid data, then take Y as valid and X becomes optional field. To do this, I tried to use Behaviour but couldn't do it. When I provided invalid data to X, Y didn't change to required field. the same is true for X.

[Mark Markov]

Hello @Gebremeskel Ambasager Tetemke

Where are you place you code? 

It must be placed on field X and Y, and not initialiser.

Initialiser runs only once when form loaded.