relay 0.2.0

Library which uses modified BLoC pattern to listen to multiple updates in single builder widget.

Relay

Library which uses modified BLoC pattern to listen to multiple updates in single builder widget.

Import

import 'package:relay/relay.dart';

Example

Through simple implementation you can relay update from station and subscribe via RelayBuilder.

RelayBuilder Widget can listen to more than one updates you can provide observers parameter a list of updates.

Like in below example,

• first relay builder widget observes only on counter.
• second relay builder widget observes on both counter and name.

enum ExampleUpdate { counter, name, message }

class ExampleStore extends Store<ExampleUpdate> {
  int counter = 0;
  String name = '';
  String snackBarMessage;

  void increment() {
    if (counter < 10) {
      counter++;
      relay(ExampleUpdate.counter);
    } else {
      snackBarMessage = 'Maximum Limit Reached';
      relay(ExampleUpdate.message);
    }
  }

  void updateName(String text) {
    name = text;
    relay(ExampleUpdate.name);
  }
}

class Example extends StatefulWidget {
  @override
  ExampleState createState() => ExampleState();
}

class ExampleState extends State<Example>
    with ProviderMixin<ExampleStore, ExampleUpdate> {
  void onUpdate(ExampleUpdate update) {
    if (update == ExampleUpdate.message)
      Scaffold.of(context).showSnackBar(
          SnackBar(content: Text(getStore(context).snackBarMessage)));
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        child: Center(
          child: Column(
            children: <Widget>[
              RelayBuilder<ExampleStore, ExampleUpdate>(
                store: getStore(context),
                observers: [ExampleUpdate.counter],
                builder: (context, station) => Text('${station.counter}'),
              ),
              RelayBuilder<ExampleStore, ExampleUpdate>(
                store: getStore(context),
                observers: [ExampleUpdate.name, ExampleUpdate.counter],
                builder: (context, station) =>
                    Text('${station.name} : ${station.counter}'),
              ),
              TextField(
                onChanged: getStore(context).updateName,
                decoration: InputDecoration(
                  labelText: 'Name',
                ),
              )
            ],
          ),
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: getStore(context).increment,
        child: Icon(Icons.add),
      ),
    );
  }
}

Example With Use of Provider.

• main.dart

  Wrap Material App with Provider

    class MyApp extends StatelessWidget {
      @override
      Widget build(BuildContext context) {
        return Provider(
          manager: StoreManager(
            stores: {
              ExampleStore: () => ExampleStore(),
            },
          ),
          child: MaterialApp(
            title: 'Relay Example',
            home: Example(),
          ),
        );
      }
    }

• Widget

Extend ProviderWidget and ProviderState then you can access the station object in deep hierarchies also.