Question

如果我从一个隔离区向主要隔离区发送邮件，则主要隔离区无法接收完整的邮件。我的测试代码很糟糕：

import 'package:flutter/material.dart';
import 'dart:isolate';
import 'dart:async';

void main() {
  init();
  runApp(MyApp());
}

void test(SendPort port) {
  var cnt = 1;
  Timer.periodic(new Duration(microseconds: 10), (Timer timer){
    port.send(cnt++);
  });
}

void init() {
  ReceivePort port = new ReceivePort();
  print("create an isoalte...");
  Isolate.spawn(test, port.sendPort);
  port.listen((msg){
    print("the return is: $msg");
  });
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(

        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {

    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(

        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

如果我每秒发送一次消息是可以的，那么频率将影响主隔离接收消息，如果主isoalte繁忙，它将丢弃消息吗？端口是否使用消息队列相互通信？是同步还是异步？

Answer 1

端口通信使用消息队列并异步接收事件。如果正在运行的代码没有返回事件循环，则隔离将不会处理任何传入消息。它仍然应该接收所有消息并缓冲它们，直到有时间调用处理程序为止。

通过端口的两个隔离发送消息将丢弃dart 2.5版本的一些消息

1 个答案: