Difference between Callable Object for execution and Display

Question

Hi,
         I am new to Guided Procedures.When i am creating a callable object under an Action ,i find callable object for execution and callable object for display in the dropdown.What is the difference between the two types of callable objects.
Thanks,
Bala

Answer 1

Hi Bala,
GP comes with a set of registered callable object types that define which applications you can directly expose as callable objects and enable their handling in the context of GP processes.
So the different COs can handle your specific application requirements or process flow requirements appropriately at runtime.
You refer those COs in actions. To make the action functional, you attach at least one callable object to it. In addition to the object that is executed when the action is called, you can attach a callable object that is displayed after the execution. The first one is mandatory. You must attach a callable object for execution. It can be either a callable object with a visible part, such as a Web Dynpro or BSP callable object, or one for background execution.
Optionally, you can attach a callable object for display. It is required to have a visible part – for example, you cannot select a callable object for background execution.
At runtime, this object is displayed if the processor wants to open the process step after it has been completed, or if a process contributor has view permissions on the action.
To make it easier, I will give you an example with submitting and approving a composite form. Say, the employee fills in an order for something, submits it and the manager then approves or rejects it.
First, in order for the employee to view the form, you can use a Form Display callable object as a display callable object for actions where the execution object is a form. It displays the name and description of the form and provides a link for download. If the user has view permissions on the step, he or she can view the display object and download the form itself. So, this CO is connected basically with the user experience and what he/she sees displayed on the screen, no matter what happens in the background (e.g. you can have a pre-filling service in the background that prefills some fields of the form, but what the user sees is only the form fields with certain info already prefilled in them).
Next, for the manager to approve or reject the form of the employee, you need a CO that is only for execution, for example a Process Control CO for File Approval For forms, you can use it in a process in which a form is sent by e-mail. As soon as the form is submitted back to the system, the receiver can view it, save a copy of the form, and depending on his or her decision, can approve or reject it.
This really is a very simplified example, but I hope it helped a little in some way or another
Here is a link to the Callable Objects in GP documenatation, hope it also clears up some questions:
http://help.sap.com/saphelp_nw70/helpdata/en/d2/d174413aff5458e10000000a1550b0/frameset.htm
Also, a link to the documentation for exposing COs:
http://help.sap.com/saphelp_nw70/helpdata/en/08/d88041a17e060de10000000a1550b0/frameset.htm
HTH:)
Greets,
Petra