notification_dispatcher 0.4.0

Inspired by Apple's NotificationCenter. Passes information around to registered observers.

Inspired by Apple's NotificationCenter. Passes information around to registered observers.

Installing

Add the following line to your pubspec.yaml file.

notification_dispatcher: ^0.4.0

Flutter Example

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      title: 'Flutter Demo',
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key}) : super(key: key);

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  @override
  void initState() {
    super.initState();

    // Add this instance as an observer and call _incrementCounter when we
    // receive a notification with the name 'increment'.
    NotificationDispatcher.instance.addObserver(
      this,
      name: 'increment',
      callback: (_) => _incrementCounter(),
    );
  }

  @override
  void dispose() {
    // Make sure to remove this instance as an observer to prevent callbacks
    // from running if we receive a notification with the name 'increment'.
    NotificationDispatcher.instance.removeObserver(this);
    super.dispose();
  }

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('NotificationDispatcher Demo'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            const Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        // Post a notification with the name 'increment' to fire our
        // _incrementCounter callback.
        onPressed: () =>
            NotificationDispatcher.instance.post(name: 'increment'),
        tooltip: 'Increment',
        child: const Icon(Icons.add),
      ),
    );
  }
}