---
title: Mark Required Fields As Such
order: 61
layout: page
---

[[mark-required-fields-as-such]]
= Mark required fields as such

Don’t make your users guess which fields in your form are required. Mark
them as such:

[source,java]
....
TextField tfFirstName = new TextField("First name");
tfFirstName.setRequired(true);
tfFirstName.setRequiredError("First name must be filled in!");
....

Required fields get a small *asterisk* after the caption (or after the
field itself, if it doesn’t have a caption), which is quite universally
understood to mean “required”. Of course, it certainly doesn’t hurt to
have “footnote” somewhere in your form that explains it anyway.

image:img/reqfield.png[Required field with asterisk]

Marking a field as required also implicitly adds a non-empty validator
to the field, preventing the form from being submitted unless a value
has been entered. The error message associated with that validator can
be set with the *setRequiredError()* method:

[source,java]
....
TextField tfFirstName = new TextField("First name");
tfFirstName.setRequired(true);
tfFirstName.setRequiredError("First name must be filled in!");
....

image:img/errortooltip.png[Required field with error]

Think carefully about which fields really are required, though. For
instance, asking unnecessary questions in a sign-up form has a tendency
to make people either cancel signing up, or enter nonsense information
in fields they deem nonessential. Only mark as required fields that you
really need the user to fill in, right there and then.