Vaadin 7 Validation (BeanValidator and setrequired) - vaadin

Question

Hi I have just started Vaadin 7 and have got the BeanValidator working. But, I have some issues. The code I am using is the following:
BeanItem<RegisterBean> item = new BeanItem<RegisterBean>(new RegisterBean());
final FieldGroup binder = new FieldGroup(item);
final TextField email = new TextField("email");
email.addValidator(new BeanValidator(RegisterBean.class, "email"));
The validates fine using the BeanValidator. With the #NotNull tag I am able to validate for Null values as well. However, I would like to give the user visual clues that the field in the form can't be left blank. For this, I used:
email.setRequired(true);
However, after adding the setRequired the BeanValidation for the form no longer works?
Is this a limitation?
How do I get around it?

Answer 1

You should probably rely on the bean validation itself and use the fieldgroup.
My model looks as follows:
#NotNull(message="Please enter a valid email address.")
#Email(message="Please enter a valid email address.")
#Size(min = 3, max = 255, message="Please enter a valid email address.")
#Column(name="P_EMAIL", nullable=true, length=255)
private String email;
In your view do either buildAndBind
Field<?> email = binder.buildAndBind("email");
Or use the annotation #PropertyId("email") in your field declaration. The rest is magic.
Instead of FieldGroupuse BeanFieldGroup.
A problem will be that validation is made preliminary. So install the validators on click. More to that topic can be found here: http://morevaadin.com/content/bean-validation-and-vaadin-comprehensive-example/

Answer 2

To complete the example above, using a BeanFieldGroup, as it got validators, you can use the setValidationVisible method of an AbstractField to turn off preliminary validation, then to turn on in a blurListener and in the buttons clickListeners.
AbstractTextField cName = binder.buildAndBind("Name","name", AbstractTextField.class);
cName.setNullRepresentation("");
cName.setValidationVisible(false);
cName.addBlurListener(new MyBlurListener(cName)); //<-- turn on setValidationVisible there
myButton.addClickListener(event -> {
try {
cName.setValidationVisible(true);
binder.commit();
} catch (CommitException e){
Notification.show("Sending error");
}
});