notifier

Update any widget, from anywhere at anytime.

Getting Started

Inspired from Broadcast Receiver in Android.

Works for both iOS and Android.

Add the following dependency to your project's pubspec.yaml.
notifier: <latest_version>
There are two methods that make the core of Notifier.
  • notify(action, data) - Sending data for a certain action.
  • register(action, callback) - Listening to data changes for a certain action.
Steps
  • Add NotifierProvider at root of project's Widget tree.
void main() {
  runApp(
    NotifierProvider(
      child: MyApp(),
    ),
  );
}
  • Register a callback for a certain action in your Widget tree.
@override
  Widget build(BuildContext context) {
    return Column(
      children: <Widget>[
        Text('Data from Notifier:'),
        Notifier.of(context).register<String>('action', (data) {
          return Text('${data.data}');
        }),
      ],
    );
  }
  • From anywhere in your application, call the notify method.
@override
  Widget build(BuildContext context) {
    Notifier _notifier = NotifierProvider.of(context);

    return Scaffold(
      body: Center(
        RaisedButton(
          child: Text('Notify'),
          onPressed: () {
            _notifier.notify('action', 'Sending data from notfier!');
          },
        ),
      ),
    );
  }

Things to be aware of!

  • If a callback is registered on an action with a specific data type T, then passing data with data type other than T in notify method will throw error.

Libraries

main_notifier
notifier
notifier_data
notifier_impl
notifier_provider

Dart

VM

dart:ffi
Foreign Function Interface for interoperability with the C programming language. [...]

Web

dart:html
HTML elements and other resources for web-based applications that need to interact with the browser and the DOM (Document Object Model). [...]
dart:js
Low-level support for interoperating with JavaScript. [...]
dart:js_util
Utility methods to efficiently manipulate typed JSInterop objects in cases where the name to call is not known at runtime. You should only use these methods when the same effect cannot be achieved with @JS annotations. These methods would be extension methods on JSObject if Dart supported extension methods.