IsolateFlutter

IsolateFlutter is a useful package for you who want to make and manage Isolate. It is based on dart:isolate so it only support iOS and Android.

It's like compute(): Spawn an isolate, run callback on that isolate, passing it message, and (eventually) return the value returned by callback. But it not top-level constant so you can create multiple Isolates at the same time.

Requirements

Flutter >=3.35.0, Dart ^3.9.0. Verified against Flutter 3.44.

Installation

dependencies:
  isolate_flutter: ^4.0.0

import 'package:isolate_flutter/isolate_flutter.dart';

Usage

Create and start an isolate

final _value = await IsolateFlutter.createAndStart(_testFunction, 'Hello World');
print(_value);

Create and manager an isolate (not run immediately)

Create an isolate. It returns null if the isolate could not be created:

final IsolateFlutter? _isolateFlutter = await IsolateFlutter.create(_testFunction, 'Hello World');

Start and get the value returned by _testFunction

final _value = await _isolateFlutter?.start();
print(_value);

Pause a running isolate
```
_isolateFlutter?.pause();
```
Resume a paused isolate
```
_isolateFlutter?.resume();
```
Stop and dispose a an isolate
```
_isolateFlutter?.stop();
```
stop() kills the isolate, so work that is still in flight is abandoned. The Future returned by start() never completes in that case.

Reading the state

_isolateFlutter?.isRunning;
_isolateFlutter?.isPaused;
_isolateFlutter?.isStopped; // also true before the isolate has ever started

Example test function

The callback must be a top-level function or a static method — it cannot be a closure or an instance method, because it has to be sent to another isolate.

Future<String> _testFunction(String message) async {
  Timer.periodic(const Duration(seconds: 1), (timer) => print('$message - ${timer.tick}'));
  await Future<void>.delayed(const Duration(seconds: 30));
  return '_testFunction finish';
}

Errors

If the callback throws, the error and its stack trace are forwarded to the calling isolate, so start() / createAndStart() rethrow the original error:

try {
  await IsolateFlutter.createAndStart(_testFunction, 'Hello World');
} on StateError catch (e) {
  print(e);
}

Author

IsolateFlutter is developed by Thong Dang. You can contact me at thongdn.it@gmail.com

If you like my project, you can support me or star (like) for it.

Thank you! ❤️