How to set the form validation only for the fields that are shown

Question

In the admin side I have a XML form with 2 fields as below. Both the fields are marked as required=true

<field name="field1"
  type="text"
  label="Field1"
  required="true"/>

<field name="field2"
  type="text"
  label="Field2"
  required="true"/>

In the admin form (default.php) the fields are sown as below. field2 is required only on certain condition.

echo $this->form->renderField('field1');
if (condition){
  echo $this->form->renderField('field2');
}

When this form is getting submitted the server side validation validates both the fields irrespective on what is displayed on the form. I want to setup in such a way that validation only validates what's in the form.

Answer 1

I managed to achieve this via setFieldAttribute. In the XML form I removed the field2 required property and set that dynamically in the form as below.

echo $this->form->renderField('field1');
if (condition){
  $this->form->setFieldAttribute('field2','required','required');
  echo $this->form->renderField('field2');
}

Not sure whether this is the right approach however it works great...