onEvent method
Called whenever an event is added to the Bloc.
A great spot to add logging/analytics at the individual Bloc level.
Note: super.onEvent should always be called first.
@override
void onEvent(Event event) {
  // Always call super.onEvent with the current event
  super.onEvent(event);
  // Custom onEvent logic goes here
}
See also:
- BlocObserver.onEvent for observing events globally.
Implementation
@protected
@mustCallSuper
void onEvent(Event event) {
  // ignore: invalid_use_of_protected_member
  _blocObserver.onEvent(this, event);
}