If you want a Context, runtime object, and runtime value#Runtimeobject to change its State on a Transition, you need to define a State Machine diagram elements#Trigger on the Transition by Assigning Event Type. A runtime object will change its State when it receives a Trigger on the Transition. A Trigger can be a Event#SignalEvent, a Event#TimeEvent, or a Event#ChangeEvent.
The StopWatch's State Machine diagram with defined Triggers on the Transitions.
Tip
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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