emit method
Updates the state
to the provided state
.
emit does nothing if the state
being emitted
is equal to the current state
.
To allow for the possibility of notifying listeners of the initial state, emitting a state which is equal to the initial state is allowed as long as it is the first thing emitted by the instance.
- Throws a StateError if the bloc is closed.
Implementation
@protected
@visibleForTesting
@override
void emit(State state) {
try {
if (isClosed) {
throw StateError('Cannot emit new states after calling close');
}
if (state == _state && _emitted) return;
onChange(Change<State>(currentState: this.state, nextState: state));
_state = state;
_stateController.add(_state);
_emitted = true;
} catch (error, stackTrace) {
onError(error, stackTrace);
rethrow;
}
}