BlocActionMixin<ACTION, S> mixin

General purpose mixin on BlocBase. Provides new method BlocActionMixin.dispatch, to emit new action event.

Adds new stream with elements of type ACTION, independent of o Bloc state. It can be useful, when widget should react on "Actions" like showing popups, toast, navigation etc. Emitted actions does not affect widget itself.

BlocActionMixin is easy to use and connect to existing BlocBase classes. Simply:

class MessageActionCubit extends Cubit<BuildState> with BlocActionMixin<String, BuildState> {
  ...
}

Handling actions on the widget side, is simple. Just use useActionListener, like so:

 @override
  Widget build(BuildContext context) {
    // Handle separate action stream with values other than a state type
    useActionListener(cubit, (String action) {
       //do sth with action
      _showMessage(context, action);
    });
   ...
  }

You can also filter your actions using actionWhen.

    useActionListener(
      cubit,
      (String action) {
        //do sth with filtered action
        _showMessage(context, action);
      },
      actionWhen: (previousAction, action) => true,
    });

See also ActionCubit and ActionBloc

Mixin Applications

• ActionBloc
• ActionCubit

Properties

actions → Stream<ACTION>

no setter

actionStreamController → StreamController<ACTION>

no setter

hashCode → int

The hash code for this object.

no setter, inherited

isClosed → bool

Whether the bloc is closed.

no setter, inherited

previousAction ↔ ACTION?

getter/setter pair

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

state → S

The current state.

no setter, inherited

stream → Stream<S>

The current stream of states.

no setter, inherited

Methods

addError(Object error, [StackTrace? stackTrace]) → void

Reports an error which triggers onError with an optional StackTrace.

inherited

close() → Future<void>

Closes the instance. This method should be called when the instance is no longer needed. Once close is called, the instance can no longer be used.

dispatch(ACTION action) → void

emit(S state) → void

Updates the state to the provided state. emit does nothing if the state being emitted is equal to the current state.

inherited

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

onChange(Change<S> change) → void

Called whenever a change occurs with the given change. A change occurs when a new state is emitted. onChange is called before the state of the cubit is updated. onChange is a great spot to add logging/analytics for a specific cubit.

inherited

onError(Object error, StackTrace stackTrace) → void

Called whenever an error occurs and notifies BlocObserver.onError.

inherited

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited