flutter - 如何创建一个新的其他流流，返回所有发出的值的列表（块模式）？

Question

我有三个这样的流：

  final _light1RoomCtlr = BehaviorSubject<String>();
  final _light2RoomCtlr = BehaviorSubject<String>();
  final _light3RoomCtlr = BehaviorSubject<String>();
  Stream<String> get getLight1Room => _light1RoomCtlr.stream;
  Function(String) get setLight1Room => _light1RoomCtlr.sink.add;
  Stream<String> get getLight2Room => _light2RoomCtlr.stream;
  Function(String) get setLight2Room => _light2RoomCtlr.sink.add;
  Stream<String> get getLight3Room => _light3RoomCtlr.stream;
  Function(String) get setLight3Room => _light3RoomCtlr.sink.add;

我想将它们全部合并，以便在需要时获取所有发出的值。

问题是..我正在使用 bloc 模式并且我没有 initState() 函数，所以我无法初始化东西..所以 dart 不会让我在同一个文件上做这样的事情：

 final List<String> _lightRooms = List<String>();
  Observable.merge([getLight1Room, getLight2Room, getLight3Room]).listen((room) =>
    _lightRooms.add(room);
  ));

我已经尝试了很多东西，但我不断收到错误消息：只有静态成员是可初始化的..或类似的东西..我如何使用反应式编程和 bloc 模式进行此操作？如果我在我需要的小部件上进行监听，我可能会丢失另一个小部件的信息。我尝试了 rxjs 示例，但在这里它不起作用，因为这只是类定义的东西。

Answer 1

您可以使用 combineLatest2、combineLatest4、combineLatest5 等

例如：

import 'dart:async';

import 'package:login_bloc/src/blocs/validators.dart';
import 'package:rxdart/rxdart.dart';

class Bloc with Validators {
  final _email = BehaviorSubject<String>();
  final _password = BehaviorSubject<String>();

  Stream<String> get email => _email.stream.transform(validateEmail);
  Stream<String> get password => _password.stream.transform(validatePassword);
  Stream<bool> get submitValid =>
      Observable.combineLatest2(email, password, (e, p) => true);

  Function(String) get changeEmail => _email.sink.add;
  Function(String) get changePassword => _password.sink.add;

  submit() {
    final validEmail = _email.value;
    final validPassword = _password.value;

    print('valid data:');
    print(validEmail);
    print(validPassword);
  }

  dispose() {
    _email.close();
    _password.close();
  }
}