isolate_contactor 1.7.0

An easy way to create a new isolate, keep it active and comunicate with it. It supports sending and receiving values between main and child isolate multiple times via stream.

Isolate Contactor

An easy way to create a new isolate, keep it running and comunicate with it. It supports sending and receiving values between main and child isolate multiple times via stream, so you can build your widget with StreamBuilder and always listen to the new value from your isolate.

This package is different from the compute method, IsolateContactor allows the isolate to run, send, receive data until you terminate it. It'll save a lot of starting time.

Basic Usage (with build-in function)

There are multiple ways to use this package, the only thing to notice that the function have to be a static or top-level function to make it works.

Create a top-level or static function

double add(dynamic value) => value[0] + value[1];

Create IsolateContactor instance for that function

IsolateContactor<double> isolateContactor = await IsolateContactor.create(add);

Listen to the result of the isolate

The result will be passed into stream listener, so you need to make sure that the stream has been called before sending message to the isolate for computing.

In Dart native:

isolateContactor.onMessage.listen((message) {
  print('Result of the `add` function: $message');
});

In Flutter:

StreamBuilder(
  stream: isolateContactor.onMessage,
  builder: (context, snapshot) {
    if (!snapshot.hasData) {
      return const Center(
        child: CircularProgressIndicator(),
      );
    }
    return Text(
        'Result of the `add` function: ${snapshot.data}');
  },
),

Send data to isolate for computing

isolateContactor.sendMessage([10.0, 20.0]);

You can also await for the result

final result = await isolateContactor.sendMessage([10.0, 20.0]);

Create your own isolate function

This is also not too complicated to use, you're completely control your isolate function with this method. You just need to create a function of this form:

// Create your own function here
void isolateFunction(dynamic params) {
  // Initial the controller for child isolate
  final controller = IsolateContactorController<double>(
    params, 
    onDispose: () {
      print('Dispose isolateFunction');
    }
  );

  // Get your initialParams.
  // Notice that this `initialParams` different from the `params` above.
  final initialParams = controller.initialParams;
  print(initialParams);

  // Listen to the message receiving from main isolate
  controller.onIsolateMessage.listen((message) {
    // Do your stuff here
    final result = add(message[0], message[1]);
    
    // Send value back to your main process in stream [onMessage]
    controller.sendResult(result);
  });
}

Then create IsolateContactor for that function

IsolateContactor<double> isolateContactor =  await IsolateContactor.createOwnIsolate(
      isolateFunction,
      initialParams: 'This is initialParams',
      debugMode: true,
    );

Then you can use isolateContactor like above example

Limitation

Support web platform with limited features. The package use Future to provide the same features to Isolate.

Contributions

If you encounter any problems or feel the library is missing a feature, please feel free to open an issue. Pull request are also welcome.

To-do list

• Await for the result from isolate when using isolateContactor.sendMessage.
• Allow creating multiple child isolates at the same time to solve multiple inputs sent from main isolate. Move this feature to isolate_manager: pub | git
• Add real isolate for web platform with service-worker.js.