This model element is described in the context of statechart diagrams (see Abschnitt 20.8, „Transition“).
Remember that action states do not have explicit triggers. The transition is implicitly triggered as soon as the entry event of the action state is complete. An explicit trigger should not therefore be set.
The current release of ArgoUML will not check that this constraint is met.
Transitions to and from an ObjectFlowState are dashed, to distinguish object flow from control flow.