If you are modeling an active State configuration on a State Machine diagram, and you need to represent several States as being active concurrently, you can achieve this by firstly creating a State Machine element or Composite State element and secondly subdividing that element with Regions. You set out the State configuration such that there is only ever one of the concurrently active States per Region. Multiple transitions can occur from a single event dispatch, so long as the similarly-triggered transitions are divided by Regions.

Regions display on an element on a diagram as subdivisions of a structured compartment, underneath other compartments such as tags, responsibilities, attributes and operations.

Access    Right-click on element | Advanced | Define Concurrent Substates

Create a Region in a Composite State or State Machine element




On the State Regions dialog, the Name field defaults to <anonymous>.



If you want to create Regions that have no title, simply click on the Save button once for each Region to create.

If you want to create named Regions, type the name and click on the Save button for each Region.



When you have created as many Regions as you need, click on the Close button.

You can now populate the Regions with elements from the State Diagram Toolbox.



·Changes to the elements in a Region are committed when the diagram is saved; if you want to undo the changes, reload the diagram without saving
·Any States, State Nodes (Pseudo-States) or Synch elements added to a Region are owned by that Region and, ordinarily, cannot be dragged into another Region; however, if you attempt to drag a State between Regions, the move embedded element to region menu option displays which - if you select it - allows the transfer to complete

Learn more

·State Machines (diagrams)
·State Machine (element type)