Suppose we have the same classes structure as shown in the How to: Use UpCasting help topic.
Our goal is to provide two details collections into a DetailView that will allow end-users to view objects of the LocalEmployee and ForeignEmployee classes separately in a Department DetailView.
In order to do this, we will declare two calculated details collections in the Department class and also write some code to update these collections when objects are added in or deleted from the main (associated) Employees collections.
By design the Employees collection is intended to list both local and foreign employees and also to allow end-users to perform any operations with them. The LocalEmployees and ForeignEmployees collections are intended to view objects only. So, the corresponding nested ListViews will be readonly.
How to: Set Relationships Between Objects
How to: Calculate a Property Value Based on Values from a Detail Collection
How to filter persistent objects against their type
Collection properties and the New/Delete/Link/Unlink Actions
Files to look at:• BO.cs (VB: BO.vb)