Defining an attribute which value depends on value of others

[raweck]

How to define for a task or a document an attribute which value depends on value of another or others attributes?

Example:
We have two attributes for task: "Country" and "Football team". User can set these attributes selecting positions on lists. When user set the "Country" attribute, the "Football team" attribute should allow set only teams from this country.

Thanks for any answer

[raweck]

How can I call a component-generator class java function when user set/modify another attribute on form?
Is it possible to call java function of component-generator class when events in web browser occurs (onclick, onchange,…)?
If it is possible maybe it is my way to implement attribute which depends on value of others.

Best regards

[gavinc]

It sounds possible, but not something we've done before.

On the component that needs to change the value of another you can setup a method to call when the list is changed via the JSF "valueChangeListener" attribute, this will force a page refresh and therefore force the other list to re-draw.