disposing 1.0.0+1

Disposing is a flutter package adds dispose method on many classes.

disposing

Disposing is a flutter package adds dispose method on many classes. It also provides Disposable and DisposableBag to easy to manage disposable instances.

Installation

Add dependencies to your pubspec.yaml

Dart only

dependencies:
  disposing: <LATEST_VERSION>

Flutter

dependencies:
  flutter_disposing: <LATEST_VERSION>

How to Use

1. First, you need to import disposing.dart file

import 'package:disposing/disposing.dart';

2. Convert instance to disposable

// You can convert StreamSubscription, StreamController, Timer and so on.
final streamDisp = stream.listen((v) => {}).asDisposable();
final timerDisp = timer.asDisposable();

3. (Optional) Add disposable instances to DisposableBag

final bag = DisposableBag();
bag.add(streamDisp);
bag.add(timerDisp);

Or you can add disposable directly

stream.listen((v) => {}).disposeOn(bag);
timer.disposeOn(bag);

4. Dispose them!

// Without DisposeBag
await streamDisp.dispose();
await timerDisp.dispose();

// With DisposeBag
await bag.dispose();

For Flutter

flutter_disposing adds Listenable extension methods and DisposableBagStateMixin class.

Listenable

Listenable is a base class of ChangeNotifier which is used by TextEditingController, FocusNode, ValueNotifier and many other flutter classes.

Use addDisposableListener to adds a listener function and returns disposable instance.

final controller = TextEditingController();
final disp = controller.addDisposableListener(() => print(controller.text));

DisposableBagStateMixin

This mixin adds disposeBag variable and dispose it when the widget's state is being disposed.

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

  @override
  _ExampleWidgetState createState() => _ExampleWidgetState();
}

class _ExampleWidgetState extends State<ExampleWidget>
    with DisposableBagStateMixin {
  final controller = TextEditingController();

  @override
  void initState() {
    Timer.periodic(Duration(seconds: 1), (t) => {}).disposeOn(disposeBag);
    controller.addDisposableListener(() => print(controller.text)).disposeOn(disposeBag);
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return TextField(
      controller: controller,
    );
  }
}

using

using is an utility method which will dispose disposable instance automatically after the callback execution is finished (like C# using statement).

await using(someDisposable, (disposable) async {
  // do something...
});
assert(someDisposable.isDisposed, true);