- Contract need listener do something and need callback when job is done
dynamic event) → void
brodcast a new event on the event bus with the specified
Contract event) → Future< bool>
- caller open contract, need call back when job done
) → Future< void>
- This is generally only in a testing context.
T>( dynamic func(dynamic)) → StreamSubscription
Listens for events of Type
Tand its subtypes.