GUI Development Paradigm

Question

Hi everybody!
I'm quite new in ALBPM and I have some questions about it, especially about user interfaces.
I've been developing JSP aplications (using MVC frameworks) for a long time, and I can't figure out how does it fit in the ALBPM world.
What's the paradigm for GUI development? At first, I believe the screenflow should act like the controler, the BPM object is the model, and the custom JSPs are the views.
But... sincerely for me, the Screenflow/BPM object/Custom JSPs seem less flexible than a regular MVC (Struts, JSF, ...)
My question is: Is it mandatory to use screenflows, or I'm able to use a MVC architecture inside ALBPM? If it's possible how should I implement it?
For example: I have a custom JSP with some menu items, and this items are links to other JSP pages. This behaviour should
be modeled using screenflows or can I use another approach? What's the best practice for this task?
In MVC architecture, the menu will be inside an html form with an action pointing to a servlet (a controller). And what about screenflows?
Well, I'd like to hear some opinions about this, especially because i'm triyng to get used to BPM paradigm, and in my opinion the best approach for this is hearing from people who had experienced this situation.
Thanks in advance,
Thiago

Answer 1

Hi Thiago,
I think I see what you're asking. Let me know if I'm missing your point.
I personally try to have a Model version of the BPM Object. I'll build this object first. This object just has the attributes, groups and methods I need. This object will be used to pass information from the process into the individual screenflows and procedures and subprocesses.
I'll then create a View version of the same BPM Object. I create this View BPM object is created by creating an heir from the original Model BPM Object (right mouse click the Model BPM Object and click "Create Heir"). When I know I'll need to collect several Model BPM Objects into one View object, I'll instead add these as attributes (each attribute would be of the type of the desired Model BPM Object). Built this way, this View Object would have all the attributes and methods of the Model object. You'd also add to this View Object the presentations you'll later use inside the screenflows and any methods you'll use inside these presentations.
At this point, you'll have a clean Model BPM Object - uncluttererd by presentations and presentation methods. You'll have View BPM Objects that will be used exclusively inside Global, Interactive, Global Creation and Interactive activity screenflows.
When I create a screenflow I always do it after I first have created a process with a BPM Object as an instance variable already defined in it. This object does not have to be perfectly defined. It just should be present in the process. If I decide later that I need additional attributes and methods, these can be added at any point in the development lifecycle. This object is the Model object I'll pass to my screenflows.
Second, after creating this process with the BPM Object (usually the process at this stage just shows the "Happy Path") I'll add the necessary Interactive activities used in the process. (finally getting to your question) I then create screenflows for each of the Interactive activities (right click the activity -> Main task -> pick screenflow from the dropdown -> New). As you're doing this from this panel, be sure to map the Model object as both an incoming and outgoing variable into and out of the screenflow. Some people also map the "result" predefined variable as an outgoing variable from the screenflow. If you do it this way, you'll not have to do any of the 4 argument mappings you'd have to do had you added the incoming and outgoing variables manually. If you decide to do this manually, many times you'll find yourself spending an hour tracing down where you lost the contents / changes made inside screenflows.
This best practice makes it easy to pass in and get back the Model object to and from the screenflow. Once inside the screenflow, you'd do the Model to View to Model object mapping described in my earlier post.
hth,
Dan