If you want a runtime object to change its State on a Transition, you need to define a Trigger on the Transition by assigning an Event Type to a Transition. A runtime object will change its State when it receives a Trigger on the Transition. A Trigger can be a Signal Event, a Time Event, or a Change Event.


The StopWatch's State Machine diagram with defined Triggers on the Transitions.


Optionally, you can also use a Send Signal Action of an Activity as a Signal Event of Transition. As shown in the following figure, the stopped State can wait for the off Send Signal Action of the do Activity to proceed to the final State.

The off Send Signal Action of the do Activity as a Signal Event of Transition.

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