【问题标题】:Bidirectional communication with isolates in Dart 2Dart 2 中与隔离物的双向通信
【发布时间】:2019-02-15 00:17:22
【问题描述】:
我正在尝试隔离,我想知道如何让其中一些进行繁重的计算,当根隔离询问他们当前的计算值时,他们会“按需”响应。
据我所知,唯一可以用作新创建的隔离消息的对象是 SendPort,这意味着只有生成的隔离可以与根隔离。我尝试发送一个 元组,但由于 ReceivePort 不是 SendPort,它被认为是非法的。
简而言之:
root good
root 隔离如何?
【问题讨论】:
标签:
dart
dart-isolates
dart-2
【解决方案2】:
用Gunter 的comment 我做了这个:
import 'dart:async';
import 'dart:io';
import 'dart:isolate';
Stopwatch stopwatch = new Stopwatch();
main(args) async {
ReceivePort rPort = new ReceivePort();
rPort.listen((data) {
print("<root> $data received");
if (data is List) {
String action = data[0];
if (action == "register") {
(data[1] as SendPort).send(stopwatch.elapsedMilliseconds);
}
}
});
stopwatch.start();
await Isolate.spawn(elIsolate, rPort.sendPort);
print("isolate spawned in ${stopwatch.elapsedMilliseconds} msecs"); //isolate spawned in 377 msecs
}
void elIsolate(SendPort sPort) {
ReceivePort rPort = new ReceivePort();
rPort.listen((data) {
print("<Isolate> '$data' received"); //<Isolate> '387' received
});
sPort.send(["register", rPort.sendPort]);
}
而使用Kevin 的answer 代码简化为:
import 'dart:async';
import 'dart:io';
import 'dart:isolate';
import 'package:stream_channel/stream_channel.dart';
Stopwatch stopwatch = new Stopwatch();
main(args) async {
ReceivePort rPort = new ReceivePort();
IsolateChannel channel = new IsolateChannel.connectReceive(rPort);
channel.stream.listen((data) {
print("<root> '$data' received at ${stopwatch.elapsedMilliseconds} msecs"); //<root> 'hello world' received at 1141 msecs
channel.sink.add(stopwatch.elapsedMilliseconds);
});
stopwatch.start();
await Isolate.spawn(elIsolate, rPort.sendPort);
print("isolate spawned in ${stopwatch.elapsedMilliseconds} msecs"); //isolate spawned in 1111 msecs
}
void elIsolate(SendPort sPort) {
IsolateChannel channel = new IsolateChannel.connectSend(sPort);
channel.stream.listen((data) {
print("<Isolate> '$data' received");
});
channel.sink.add("hello world");
}