df_will_dispose 0.5.3

A lightweight solution for managing the cancellation and disposal of resources in Flutter.

DF - Will Dispose

Dart & Flutter Packages by DevCetra.com & contributors.

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Summary

This package provides a lightweight solution for managing the cancellation and disposal of resources in Flutter. It's designed to streamline your code by allowing you to mark resources for cancellation or disposal at the time of their definition. The package includes both WillDispose and WillCancel utilities, which work similarly but target different types of resources: WillDispose for disposables like controllers and notifiers, and WillCancel for cancellables like stream subscriptions.

Quickstart

• Use this package as a dependency by adding it to your pubspec.yaml file (see here).
• For stateful widgets, use WillDisposeState or WillCancelState instead of State, or simply mix in DisposeMixin and WillDisposeMixin or CancelMixin, and WillCancelMixin to your existing state classes.
• Define your resources using the willDispose or willCancel functions, which will automatically dispose of or cancel the resource when the widget is removed from the widget tree.
• Any resource with a dispose() or cancel() method can be managed. If a resource does not have the appropriate method, NoDisposeMethodDebugError or NoCancelMethodDebugError will be thrown during disposal or cancellation.
• Common disposable resources include ChangeNotifier, ValueNotifier, FocusNode, most Flutter controllers, and Pods. Common cancellable resources include the StreamSubscription, CancelableOperation and the Timer.
• You can also create your own classes that implement DisposeMixin or CancelMixin, enabling them to work seamlessly with WillDisposeMixin and WillCancelMixin.
• For your convenience, here are simplified versions of the mixins that you can directly copy to your project if you'd prefer not to include this dependency.

Example 1 - Mixins:

DisposeMixin and WillDisposeMixin can be applied to any class to efficiently manage disposable resources. For StatefulWidget, you can further simplify your code by using WillDisposeState instead of State. These mixins allow you to easily mark resources like TextEditingController and ValueNotifier for automatic disposal when the widget is removed from the widget tree. This approach ensures that all resources are properly cleaned up without requiring manual intervention, streamlining resource management in your stateful widgets.

class _CounterState extends WillDisposeState<Counter> {
  // Define resources and schedule them to be disposed when this widget ia
  // removed from the widget tree.
  late final _secondsRemaining = willDispose(ValueNotifier<int>(60));
  late final _tickCounter = willDispose(ValueNotifier<int>(0));
  late final _timer = willDispose(
    Timer.periodic(
      const Duration(seconds: 1),
      _onTick,
    ),
  );

  void _onTick(Timer timer) {
    if (_secondsRemaining.value > 0) {
      _secondsRemaining.value--;
      _tickCounter.value++;
    } else {
      timer.cancel();
    }
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: [
        ValueListenableBuilder<int>(
          valueListenable: _secondsRemaining,
          builder: (context, value, child) {
            return Text(
              '$value seconds remaining',
              style: const TextStyle(fontSize: 24),
            );
          },
        ),
        const SizedBox(height: 20),
        ValueListenableBuilder<int>(
          valueListenable: _tickCounter,
          builder: (context, value, child) {
            return Text(
              'Ticks: $value',
              style: const TextStyle(fontSize: 24),
            );
          },
        ),
      ],
    );
  }

Example 2 - BuildContext:

In some cases, you may prefer or need to manage disposable resources within a StatelessWidget, or you might use a StatefulWidget but you don't want to incorporate the mixins. The willDispose method can still be used effectively in these scenarios by leveraging the BuildContext.

class ChatBox extends StatelessWidget {
  const ChatBox({super.key});

  @override
  Widget build(BuildContext context) {
    // Define resources and schedule them to be disposed when this widget is
    // removed from the widget tree.
    final textEditingController = context.willDispose(TextEditingController());
    final focusNode = context.willDispose(FocusNode());

    return Row(
      children: [
        TextField(
          controller: textEditingController,
          focusNode: focusNode,
        ),
        ElevatedButton(
          onPressed: () {
            final text = textEditingController.text;
              print('Submitted: $text');
            textEditingController.clear();
            focusNode.requestFocus();
          },
          child: const Text('Submit!'),
        ),
      ],
    );
  }
}

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Contributing and Discussions

This is an open-source project, and we warmly welcome contributions from everyone, regardless of experience level. Whether you're a seasoned developer or just starting out, contributing to this project is a fantastic way to learn, share your knowledge, and make a meaningful impact on the community.

Ways you can contribute:

• Buy me a coffee: If you'd like to support the project financially, consider buying me a coffee. Your support helps cover the costs of development and keeps the project growing.
• Share your ideas: Every perspective matters, and your ideas can spark innovation.
• Report bugs: Help us identify and fix issues to make the project more robust.
• Suggest improvements or new features: Your ideas can help shape the future of the project.
• Help clarify documentation: Good documentation is key to accessibility. You can make it easier for others to get started by improving or expanding our documentation.
• Write articles: Share your knowledge by writing tutorials, guides, or blog posts about your experiences with the project. It's a great way to contribute and help others learn.

No matter how you choose to contribute, your involvement is greatly appreciated and valued!

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Chief Maintainer:

📧 Email Robert Mollentze at [e-mail]

Dontations:

If you're enjoying this package and find it valuable, consider showing your appreciation with a small donation. Every bit helps in supporting future development. You can donate here:

https://www.buymeacoffee.com/robmllze

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License

This project is released under the MIT License. See LICENSE for more information.