如何在 App 启动时使用 redux 启动 fetch？

Question

设置一个简单的通知计数器后。我想在应用程序开始时获取通知以显示收到了多少通知。

配置如下：减速器：

index.js

import { combineReducers } from "redux";
import posts from "./posts";
import filteredPosts from "./filteredPosts";
import notifications from "./notifications";

export default combineReducers({
  posts,
  filteredPosts,
  notifications
});

notification.js

import * as types from "../actions/types";
const initialState = [];

export default (state = initialState, action) => {
  switch (action.type) {
    case types.LOAD_NOTIFICATIONS:
      return action.notifications;
    default:
      return state;
  }
};

动作

type.js

export const FILTERED_POST = "FILTERED_POST";
export const LOAD_POSTS = "LOAD_POSTS";
export const LOAD_NOTIFICATIONS = "LOAD_NOTIFICATIONS";

notification.js

import * as types from "./types";
import { fetchNotifications } from "../service/";

export const getNotifications = auth_token => dispatch =>
  fetchNotifications(auth_token)
    .then(res => {
      return res.json();
    })
    .then(data => {
      dispatch({
        type: types.LOAD_NOTIFICATIONS,
        notifications: data.notifications
      });
    })
    .catch(err => {
      console.log(err);
    });

和服务

index.js

import { apiEndpoint } from "./config";

export const fetchPosts = auth_token =>
  fetch(`${apiEndpoint}posts`, {
    method: "GET",
    headers: {
      Accept: "application/json",
      "Content-Type": "application/json",
      Access: auth_token
    }
  });

export const fetchNotifications = auth_token =>
  fetch(`${apiEndpoint}notifications`, {
    method: "GET",
    headers: {
      Accept: "application/json",
      "Content-Type": "application/json",
      Access: auth_token
    }
  });

api端点是api地址因此，在配置通知徽章组件并将其添加到路由器后，应用会加载帖子，因为是主屏幕而不是通知。

检查我将通知徽章组件作为主屏幕进行首次加载，但仍然没有收到通知。所以，请有人可以澄清如何在应用程序启动时或之前或之后使用 redux 获取？

export const Logged = createBottomTabNavigator(
  {
    Notification: {
      screen: Notification,
      navigationOptions: {
        tabBarLabel: "Notification",
        tabBarIcon: () => {
          <NotificationIcon />;
        }
      }
    },

Answer 1

好吧，有很多地方可能是错误的，首先我会使用像 postman, if the response is what you expect, then I would suggest creating a root component e.g AppComponent and within it, in your componentDidMount you can dispatch a getNotifications action using mapDispatchToProps

这样的工具检查端点的响应

如何在 App 启动时使用 redux 启动 fetch？

How to start fetch with redux on App start?

javascript

react-native

redux

redux-thunk

react-redux