Isolate bidirectional communication example

main.dart

import 'dart:isolate';

void main() async {
  final recvPort = ReceivePort();

  await Isolate.spawn<SendPort>((port) {
    print('[2] received port');

    final recvMsg = ReceivePort();

    port.send(recvMsg.sendPort);

    print('[2] sent my port');

    recvMsg.listen((message) {
      print('[2] Received ${message.name}');

      port.send('Thanks for ${message.name}!');
    });
  }, recvPort.sendPort);

  final recvStream = recvPort.asBroadcastStream();
  final sendPort = await recvStream.first;

  print('[1] Sending Foo');
  sendPort.send(Animal("Foo"));

  print('[1] Sending Bar');
  sendPort.send(Animal("Bar"));

  await for (final message in recvStream) {
    print('[1] #2 Replied: $message');
  }
}

class Animal {
  final String name;

  Animal(this.name);
}

/*
Results in:

[2] received port
[2] sent my port
[1] Sending Foo
[1] Sending Bar
[2] Received Foo
[2] Received Bar
[1] #2 Replied: Thanks for Foo!
[1] #2 Replied: Thanks for Bar!


Note: for simplicity, this will hang just because it's awaiting forever
*/