BC4J - To get the detail of details in a Master-Detail relationship

Question

Hi,
I am developing an application in JDev using Buss Components for Java.
I need to show the details from the details in a Master-Detail relationship of ViewLink Objects.
e.g I am browsing through a list of book publishers, if I pick one book publisher, all the books published by this publisher should be displayed. And when I pick one book out of these, the list of buyers should appear for this book.
Is it possible to do it via the wizards in JDev?
If not, is their any other way of doing it?
Thanks,
Any help would be appreciated.
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Answer 1

Sure. Arbitrary levels of master/detail are easy to handle. It's just the first time you set it up in the "Data Model" panel of your Application Module, the UI gestures may not be the most obvious.
Depending on whether you need to just browse the data, or both browse and update it, you would decide whether or not you need underlying Entity Objects for Publisher, Book, and Buyer.
To keep it simple, just assume you want to browse so the Entity Objects are not required to be involved.
You would develop three View Objects:
[list=1]
[*]Publishers - with a query like SELECT publisher_name, publisher_id FROM PUBLISHER ORDER BY publisher_name
[*]Books - with a query like SELECT title, isbn FROM book ORDER BY Title
[*]Buyers - with a query like SELECT name, company FROM buyer ORDER BY company, name
[list]
Then, you define two View Links:
[list=1]
[*]BooksFromPublisher - linking the Publishers view to the Books view, and
[*]BuyersForBook - linking the Books view to the Buyers view
[list]
Then, you define an Application Module that sets up the data model you want to work with in a particular application that reuses these reusable view object and view link components.
On the "Data Model" tab, you'll see the master/detail views available in the "Available" list like this:
- Publishers
|
+- Books
- Books
|
+- BuyersTo construct a master/detail/detail view with these "raw ingredients" do the following:
[list=1]
[*]Click on Publishers in the Available list, and click (>) to shuttle it into the data model
[*]In the data model tree, select the Publishers view to make it the active selection.
[*]Back in the Available list, click on the Books view that is indented under Publishers and click (>) to use Books as a detail of the current view in the data model.
[*]In the data model tree, select the Books view to make it the active selection.
[*]Back in the Available list, click on the Buyers view that is indented under Bookss and click (>) to use Buyers as a detail of the current view in the data model.
[list]
Hope this helps.
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