In EE2.x the validate function was being called even if the field wasn’t required and the function returned TRUE if the data was empty. In the new version, it seems that validate isn’t being called when the value is empty
Example, taken from the text fieldtype:
function validate($data)
{
if ($data == '')
{
return TRUE;
}Packet Tide owns and develops ExpressionEngine. © Packet Tide, All Rights Reserved.