ajwah_bloc 1.8.5 ajwah_bloc: ^1.8.5 copied to clipboard
Rx based state management library. Manage your application's states, effects, and actions easy way.
ajwah_bloc #
Rx based state management library. Manage your application's states, effects, and actions easy way.
States #
Every state class must derived from BaseState<T>
class. And it is mandatory to pass the
state name
and initialState
. The BaseState<T>
class has an abstract method Stream<T> mapActionToState(T state, Action action);
. This method should be invoked by sysytem passing current state and action. You should mutate the state based on action.
Example CounterState
import 'package:ajwah_bloc/ajwah_bloc.dart';
import 'package:ajwah_block_examples/actionTypes.dart';
class CounterModel {
int count;
bool isLoading;
CounterModel({this.count, this.isLoading});
copyWith({int count, bool isLoading}) {
return CounterModel(
count: count ?? this.count, isLoading: isLoading ?? this.isLoading);
}
CounterModel.init() : this(count: 10, isLoading: false);
}
class CounterState extends BaseState<CounterModel> {
CounterState() : super(name: 'counter', initialState: CounterModel.init());
Stream<CounterModel> mapActionToState(
CounterModel state, Action action) async* {
switch (action.type) {
case ActionTypes.Inc:
state.count++;
yield state.copyWith(isLoading: false);
break;
case ActionTypes.Dec:
state.count--;
yield state.copyWith(isLoading: false);
break;
case ActionTypes.AsyncInc:
yield state.copyWith(isLoading: true);
yield await getCount(state.count);
break;
default:
yield state;
}
}
Future<CounterModel> getCount(int count) {
return Future.delayed(Duration(milliseconds: 500),
() => CounterModel(count: count + 1, isLoading: false));
}
}
Using state in components #
Ajwah provides a comfortable way to use states in components and dispatching actions.
Just call the createStore(states:[], /*effects:[] optional*/)
method and there you go.
We can use select
method to get state
data (passing state name): select('counter')
. or select2(...)
.
These methods return Stream<T>
. Now pass this Stream inside a StreamBuilder to make a reactive widget.
Example #
StreamBuilder<CounterModel>(
stream: select<CounterModel>('counter'),
builder:(BuildContext context, AsyncSnapshot<CounterModel> snapshot) {
if (snapshot.data.isLoading) {
return CircularProgressIndicator();
}
return Text(
snapshot.data.count.toString(),
style: Theme.of(context).textTheme.title,
);
},
)
Also for dispatching state's action - we can use dispatch(...)
Effects (optional) #
Every effect class must derived from BaseEffect
class. And it is optional to pass the
effectKey
. But it's mandatory if you want conditionally remove the effects by using
store.removeEffectsByKey('effectKey')
. The BaseEffect
class has one abstract method List<Stream<Action>> registerEffects(Actions action$, Store store$);
. This function should be invoked by system passing reference of Actions and Store classes. Please keep in mind that effects should not work until you register them.
Example
import 'package:ajwah_bloc/ajwah_bloc.dart';
import 'package:rxdart/rxdart.dart';
import '../../actionTypes.dart';
class CounterEffect extends BaseEffect {
Stream<Action> effectForAsyncInc(Actions action$, Store store$) {
return action$
.whereType(ActionTypes.AsyncInc)
.debounceTime(Duration(milliseconds: 500))
.mapTo(Action(type: ActionTypes.Inc));
}
List<Stream<Action>> registerEffects(Actions action$, Store store$) {
return [effectForAsyncInc(action$, store$)];
}
}
Api #
dispatch(String actionType, [dynamic payload])
Stream<T> select<T>(String stateName)
Stream<T> select2<T>(T callback(Map<String, dynamic> state))
addState(BaseState stateInstance)
removeStateByStateName(String stateName)
addEffects(BaseEffect effectInstance)
removeEffectsByKey(String effectKey)
Stream<List<dynamic>> exportState()
importState(Map<String, dynamic> state)
addEffect(EffectCallback callback, {String effectKey})