Working with sub-process

Creating a sub-process

Create a business process diagram, with a start event and a task Announce Proposal. Connect them with sequence flow.

To create a sub-process in a continued process flow, you can make use of the resource-centric interface. Simply move the mouse pointer over the shape you want to add a sub-process after it. Press on the resource icon for creating sub-process and drag it out. Release the mouse button and name the sub-process as Collect Opinion.

Select a type for the sub-process. This step is optional. But without setting the sub-process to be an embedded sub-process, we will not be able to connect with shapes within the sub-process. We will talk in more detail in section Connecting with shapes in sub-process. Now, right click on sub-process Collect Opinion and select Type > Embedded Sub-Process from the popup menu.

Expanding a sub-process

Task and sub-process are both activities in BPMN. Sub-process defers in that it lets you define finer level of process detail by mean of sub-process diagram. Now, drill down to the sub-process diagram by clicking on the plus button in sub-process.

This creates and opens a new business process diagram. Draw the diagram as shown below.

Now, go back to the upper level by clicking on the shortcut at the top left of diagram.

You got a thumbnail of sub-process diagram show in the sub-process shape, like this:

On a side note, if you do not want to show the sub-process content in top level, click on the minus button at the bottom of sub-process shape. But we do not do this now because we need an expanded sub-process shape in order to complete the next section.

Connecting with shapes in sub-process

In a top level business process diagram, we may need to connect to shapes inside sub-process. Take this case as example, we need to connect a sequence flow with the Receive E-mail task to initiate it.

1. Select Start Event from diagram toolbar.
   
2. Click on the sub-process. This creates and attaches the start event to the border of sub-process.
   
3. Press on the end of the connector that is connecting to sub-process Collection Opinion.
   
4. Drag to the start event.
   
5. Select Sequence Flow in diagram toolbar.
   
6. Press on the start event.
   
7. Drag to Receive-Email and release the mouse button. You got a diagram like this:
   
8. Repeat the previous step to create an end event that attaches to the sub-process border. Connect the task Forward to Responsible Person to the end event with a sequence flow. Create another end event outside the sub-process and make it connect with the previous end event. After all, the diagram become:
   

Forming a sub-process diagram with tasks

We many group several flow objects in a business process diagram as a sub-process. Let's try.

1. Draw a new business process diagram like this:
   
2. Select tasks Receive Email, Give General Reply and Forward to Responsible Person.
   
3. Right click on the selection and select Form Sub-Process Diagram from the popup menu.
   
4. The three tasks are now contained by sub-process. The top level diagram now looks like this: