从ngrx / store获取数据

时间:2017-03-19 13:49:06

标签: angular ngrx

一切都适用于简单类型,但我无法使用对象。

这是我的减速机:

import { Action } from '@ngrx/store'
import { RssFeed } from "../rss/rss";

export interface AppState {
  demoData: number;
  feeds: RssFeed[];
}

const initialState: AppState = {
  demoData: 0,
  feeds: []
};

export const INCREMENT = 'INCREMENT';
export const DECREMENT = 'DECREMENT';

export function feedsReducer(state: AppState = initialState, action: Action): AppState {

  switch(action.type) {
    case INCREMENT: {

      return {
        demoData: state.demoData + 1,
        feeds: []
      }
    }
    case DECREMENT: {

        return {
          demoData: state.demoData - 1,
          feeds: []
        }
      }
    default:
      return state;
  }
}

app.module:

import { StoreModule } from '@ngrx/store';
import { feedsReducer } from './actions/rss';

imports: [
    StoreModule.provideStore({ feeds: feedsReducer })
  ],

成分:

import {Store } from '@ngrx/store';
import { AppState, INCREMENT, DECREMENT } from '../actions/rss'

export class RssComponent {

  state: Observable<AppState>;

  constructor(private store: Store<AppState>) {
    this.state = store.select('feeds');

addDemoData() {
    console.log(this.state);
    this.store.dispatch({type: INCREMENT})
  }

我在控制台中有这个状态:

Store {_isScalar: false, _dispatcher: Dispatcher, _reducer: Reducer, source: Store, select: function…}
而不是我的国家。为什么?

我认为错误在这里:

store.select('feeds');

但我不知道要传递给store.select()。

3 个答案:

答案 0 :(得分:5)

我这样解决了,但我不确定这是好方法:

store.select('feedsReducer').subscribe((data: AppState) => this.state = data );

答案 1 :(得分:2)

这是一个能够推断类型的简单解决方案(比使用字符串更好):

store
  .select(state => state.feeds)
  .do(feeds => this.feeds = feeds)
  .subscribe();

答案 2 :(得分:2)

你可以在模板中使用异步管道(记住feed是一个可观察的而不是数组):

-- feeds.component.ts

this.feeds = store.select(state => state.feeds)

-- feed.component.html

<li *ngFor="let feed of feeds | async">

参考:https://angular.io/api/common/AsyncPipe