Let's build your example:
First, you would need a subform (NameSubform) with two fields, one for the first name and one for the last name (FirstName and LastName, respectively). Let's say you also add two buttons to this subform called Add and Del which, when clicked, add and remove an instance of NameSubform, respectively. In particular, the Del button removes the instance of NameSubform to which it pertains.
Then you would need a second subform (let's call this one TotalSubform), probably located below NameSubform, which contains a drop down list. Let's call it NameDropList.
The next step is to make sure that the TotalSubform moves up or down whenever the set of instances of NameSubform is modified. To do this, you could simply make the page subform (let's give it a name, say Page1Subform) have a flowed layout. You can do this by using the Content property on the Object palette's Subform tab. Set it to
Flowed.
Now you need to make NameSubform dynamic so that you can add and remove instances. You can do this by checking the
Repeat Subform for Each Data Item check box on the Object palette's Binding tab.
Finally, the NameDropList must be setup so that it adds, removes and modifies names from its list whenever instances of NameSubform are added or removed and whenever the values in the FirstName and LastName fields change. This can be done using the drop down list's Calculate event. This event is triggered everytime the form's data changes. As such, you can write script in this event to get the total number of instances of NameSubform and then loop through each one in order to get its FirstName and LastName field values, adding them to the list as you go.
I've attached a sample form which implements your example. Please let me know if you have any questions.
Stefan
Adobe Systems
