Flutter StreamController基础应用，异步刷

StreamController基础使用，不带缓存数据

TestStreamControl 界面

import 'package:flutter/material.dart';
import 'package:flutter_home/ui/pages/paybillquery/sss.dart';

class TestStreamControl extends StatefulWidget{
  @override
  State<StatefulWidget> createState() {
    return  TestStreamControlState();
  }
}
class TestStreamControlState extends State<TestStreamControl>{
  LoginBloc _loginBloc;
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("StreamControl基础"),),
      body: Center(child: RaisedButton(onPressed: (){

        _loginBloc?.login(context, "zyj", "123456");

      },child: Text("登录"),),),
    );
  }
  @override
  void initState() {
    //初始化Stream
    _loginBloc = LoginBloc();
    super.initState();
  }
  @override
  void dispose() {
    //销毁Stream
    _loginBloc.dispose();
    super.dispose();
  }
}

LoginBloc 封装StreamController

//这里主要处理登录页面的逻辑
import 'dart:async';
import 'package:dio/dio.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_home/model/user_models.dart';  

class LoginBloc {

  UserModel _userModel;
  StreamController<UserModel> _streamController;

  LoginBloc(){
    _userModel=UserModel();
    _streamController= StreamController();
  }
  Stream<UserModel> getStream(){
    return _streamController.stream;
  }

  void login(BuildContext context,String name,String pwd) async{
    //做耗时操作
    if(name==""){
      print("请输入用户名");
      return;
    }
    if(pwd==""){
      print("请输入密码");
      return;
    } 
     
    _streamController.sink.add(_userModel);
    Response response =await Dio().request("www.baidu.com");
    if (response.statusCode == 200) {
      _userModel.phone="15732191826";
      _streamController.add(_userModel);
    } 
  }
  void dispose(){
    _streamController.close();
  }
}