I have a validator that check an input.
i what that the validator displayed "valid" if the value is valid,
and "invalid" if the value is hasnt passed the validation.
can i manage this without adding an addional lable for the valid state(by setting the visibility: true/false)?
does the validator control has am alternative value, or i have to override it?
No, the validators are designed to render text if there was a validation error, and to be unobtrusive if not.
Of course, you could create a new Validator inheriting from BaseValidator that would do this.
There's an article giving a good overview of how to do this.