UserApp form field validation without messages
This seems like it should be simple, but I'm drawing a blank here. In a simple PRD form, I want to validate my inputs. If the field is "wrong", I want to error the field, both to highlight the error, and to disable the submission of a form with an error. Seems like form.showError() is a natural fit here, but I do not want it to show a message. So this:
if (v.length == 1) // whatever
works - but with the "Field Name: ." shown at the top of the form. I don't want that. Just invalidate the field. Whatever form.showError() does to invalidate the field, but without the message part.
I can disable the Submit button, I know how to do that. It seems like it should be simple, even obvious, how to mark a form field as "invalid".