StreamSubscription sc = StreamSubscription(); Stream s = Stream(); sc.addStream(s); var bs = sc.stream.asBroadcastStream(); // this works…

1.定义消息 在开始建立webSocket之前,我们需要定义消息,如:发送人,发送时间,发送人id等.. import 'dart:convert'; class ChatMessageData { final String id; final String msg; final DateTime created; final String name; final int role; ChatMessageData( this.id, this.msg, this.name, this.role…

1. Flutter 是什么? Flutter是谷歌的移动UI框架,可以快速在iOS和Android上构建高质量的原生用户界面. Flutter可以与现有的代码一起工作.在全世界,Flutter正在被越来越多的开发者和组织使用,并且Flutter是完全免费.开源的. 2. Flutter 特性有哪些? 快速开发(毫秒级热重载) 绚丽UI(内建漂亮的质感设计Material Design和Cupertino Widget和丰富平滑的动画效果和平台感知) 响应式(Reactive,用强大而灵活的AP…

https://stackoverflow.com/questions/51396769/flutter-bad-state-stream-has-already-been-listened-to The most common form of Stream can be listened only once at a time. If you try to add multiple listeners, it will throw Bad state: Stream has already b…

Streams represent a sequence of asynchronous events. Each event is either a data event, also called an element of the stream, or an error event, which is a notification that something has failed. When a stream has emitted all its events, a single "do…