Sometimes there is the need of validating a dialog element (control) with more logic than the "required" and regular expressions only. I'm thinking about email fields, of even a check for image dimensions or colours in the image control. It would be really nice to have che possibility to set a property in the control configuration with (for instance) "validationClass" and a class that extends some interface.

Usually I do something similar extending the control I want to validate, but it should be quicker if this behaviour is in the common parent for all controls.