How to make dynamic validation Constraints in a form?

[enavarrocu]

How it's possible to make validation in a dynamic way?

Example of validation:

I have three form fields, filterType, low, high.

low must be between 0 and 128
high must be between 0 and 128
filterType can be LOW, HIGH or BOTH

if filterType is equal to "BOTH" low and high fields need to be validate
if filterType is equal to "LOW" low field need be validate
if filterType is equal to "HIGH" high field need be validate

I need an approach to do it because i try everything I can imagine. Another detail, the fields low and high will be enable or disable in relation to filterType.

Thanks in advance.

[LievenDoclo]

Add the following rules to your RulesSource when using a RulesValidator in your form:

Rules rules = new Rules(...);
rules.add(new RequiredIfTrue("low", rules.any("filter", new Constraint[] {rules.eq("both"), rules.eq("low")})));
rules.add(new RequiredIfTrue("high", rules.any("filter", new Constraint[] {rules.eq("both"), rules.eq("high")})));

[enavarrocu]

Add the following rules to your RulesSource when using a RulesValidator in your form:

Rules rules = new Rules(...);
rules.add(new RequiredIfTrue("low", rules.any("filter", new Constraint[] {rules.eq("both"), rules.eq("low")})));
rules.add(new RequiredIfTrue("high", rules.any("filter", new Constraint[] {rules.eq("both"), rules.eq("high")})));

Thanks LievenDoclo but the point is validate the values of fields low and high between 0 and 128 when filterType change. BTW filterType is a combo.

Thanks again.