I have a "Member" object. New members register with a registration form that is only used for a first time registration. This registration form collects only a small portion of the data that is allowed after registration. This is to keep the initial amount of information the new member has to enter to a minimum.
Once someone has become a member, they can add much more personal info to the database in the way of a tabbed form that has multiple objects on it. One of those tabs (for another business object) is called "ContactInfo". Here the member can put in email addresses, home page urls, phone #'s, and more. This ContactInfo business object is owned by (child relationship) the Member object and multiple objects are not allowed. Since the new member needs some way to create the new information in the ContactInfo object, I have the "Add New" button checked in the form presentation for this referred attribute. So far, everything is working great, and this newly registered member adds their contact info to the form. When they hit save, all is well.
Here's the problem...when a member is in the edit mode of the tabbed form, it always allows them to "Add New" even if they have already added this information previously. If a member decides to add another instance of this information, the program readily accepts it. I want to limit the input of this information to a one time occurrence, which I thought the parent-child relationship would accomplish when not allowing multiples. It would be nice to have the "Add New" button show up only if the instance of that object has not been created yet. Does what I'm describing require a rule, or process to accomplish, or can it be done another way? Thanks.