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Redux state does not update even when reducer called with correct data

For some reason, even though the reducer runs and console.log shows that the correct data was passed to it, the redux store was not updated.
Relevant files:
App.jsx
import {Provider} from 'react-redux';
import store from './store';
const Stack = createStackNavigator();
export default class App extends Component {
render() {
return (
<Provider store={store()}>
Store.js
import {createStore, applyMiddleware} from 'redux';
import rootReducer from '../reducers';
import thunk from 'redux-thunk';
const store = (initialState = {}) =>{
return createStore(
rootReducer,
initialState,
applyMiddleware(thunk)
)
}
export default store;
Register.tsx
...
<Pressable
style={styles.button}
onPress={() => this.props.submitRegistration(this.state)}
>
...
const mapDispatchToProps = (dispatch: any) => {
return {
submitRegistration: (data: any) => {
dispatch(UserActions.submitRegister(data))
}
}
}
export default connect(mapStateToProps, mapDispatchToProps)(Register);
UserActions
import { signUp } from '../../services/backend';
import { setUser } from '../../actions';
export function submitRegister(data: any) {
return async (dispatch: any) => {
const response = await signUp(data);
const responseData = await response.json();
if(responseData.token) {
console.log('here', responseData);
dispatch(setUser(responseData.user));
}
};
}
Action creator
export const setUser = (user: any) => ({
type: 'SET_USER',
user
});
User Reducer
import { SET_USER } from "../actions/actionTypes"
const initialState = {
user: {}
}
const User = (state = initialState, action: any) => {
switch(action.type) {
case SET_USER:
console.log('here action', action.user);
return { user: action.user}
default:
return state
}
}
export default User;
I would really appreciate any help possible. Seems like I misconfigured in someway because even when I set initial state :
const initialState = {
user: {firstName: "John"}
}
it's not reflected in the redux store.

In your action creator:
export const setUser = (user: any) => (
return {
type: 'SET_USER',
user
});

I can't fetch the data from reducer to component

I'm trying pass the data from reducer to component and receive as props.
But the data return UNDEFİNED, so I have tried console the data on reducer and action, but it's okey. There isn't any problem with the data coming from the API, but it always return to component undefined. Where is my fault?
Action
export default ProfileTab;
import axios from 'axios';
import { BASE, API_KEY } from '../config/env';
export const FETCHED_MOVIES = 'FETCHED_MOVIES';
export function fetchMovies() {
return (dispatch) => {
axios
.get(`${BASE}s=pokemon&apikey=${API_KEY}`)
.then((result) => result.data)
.then((data) =>
dispatch({
type: FETCHED_MOVIES,
payload: data.Search,
}),
);
};
}
Reducer
import { FETCHED_MOVIES } from '../actions/movies';
const initialState = {
fetching: false,
fetched: false,
movies: [],
error: {},
};
export default (state = initialState, action) => {
switch (action.type) {
case 'FETCHED_MOVIES':
return {
...state,
movies: action.payload,
};
default:
return state;
}
};
Component
import React, { Component } from 'react';
import { connect } from 'react-redux';
import PropTypes from 'prop-types';
import { fetchMovies } from '../../actions/movies';
class Case extends Component {
static propTypes = {
movies: PropTypes.object.isRequired,
};
constructor(props) {
super(props);
}
componentDidMount() {
this.props.fetchMovies();
}
onChangeHandler = (e) => {
this.setState({
input: e.target.value,
});
};
render() {
console.log(this.props.movies);
return (
<div>
<div className="movies-root">
<div className="movies-wrapper">
<div className="movies-container safe-area">
<h1>mert</h1>
</div>
</div>
</div>
</div>
);
}
}
const mapStateToProps = (state) => {
return {
movies: state.movies,
};
};
const mapDispatchToProps = {
fetchMovies,
};
export default connect(mapStateToProps, mapDispatchToProps)(Case);

Do this in the connect statement:
export default connect(mapStateToProps,{fetchMovies})(Case);
And remove the mapDispatchToProps function from your code.
Dispatching props as an object is quite incorrect. Try this, and it should work.

That's because your mapDispatchToProps function should return an object and take dispatch as parameter. Each field in your returned object should contain a function that dispatches your action.
So try something like this:
const mapDispatchToProps = dispatch => {
return {
fetchMovies: () => dispatch(fetchMovies())
}
}

Although there's already an accepted answer, I'm not sure how correct it is, as it's completely valid to pass mapDispatchToProps the way you did with the latest react (16.13.1) and react-redux (7.2.1) versions (I'm not sure about earlier versions).
Now, assuming your question contains the whole code, there are two important things missing:
Creating the store:
import { createStore } from "redux";
const store = createStore(reducer);
and passing it to the Provider component:
<Provider store={store}>
If you go ahead and do as above, you'll see that this.props.fetchMovies emits the following error:
Actions must be plain objects. Use custom middleware for async actions.
To fix it, do as it says and add a middleware, e.g. thunk:
import { createStore, applyMiddleware } from "redux";
import thunk from "redux-thunk";
const store = createStore(rootReducer, applyMiddleware(thunk));
What follows is the full code. Note that I "split" fetchMovies into two functions: sync and async, for illustrating the difference usage between the two. I also modified your code (made is shorter, mostly) for this answer's readability. You can also see a live demo here:
File app.js
import React, { Component } from "react";
import { connect } from "react-redux";
import { fetchMoviesSync, fetchMoviesAsyncMock } from "./api";
class App extends Component {
componentDidMount() {
this.props.fetchMoviesSync();
this.props.fetchMoviesAsyncMock();
}
render() {
return (
<div>
<div className="movies-root">
<div className="movies-wrapper">
<div className="movies-container safe-area">
{this.props.movies.join("\n")}
</div>
</div>
</div>
</div>
);
}
}
const mapStateToProps = (state) => ({ movies: state.movies });
const mapDispatchToProps = {
fetchMoviesSync,
fetchMoviesAsyncMock
};
export default connect(mapStateToProps, mapDispatchToProps)(App);
File api.js
export const FETCHED_MOVIES = "FETCHED_MOVIES";
export const fetchMoviesSync = () => ({
type: FETCHED_MOVIES,
payload: ["movie1", "movie2", "movie3", "movie4"]
});
export const fetchMoviesAsyncMock = () => (dispatch) => {
dispatch({
type: FETCHED_MOVIES,
payload: ["movie5", "movie6", "movie7", "movie8"]
});
};
File reducer.js
const initialState = {
movies: [],
};
export default (state = initialState, action) => {
switch (action.type) {
case "FETCHED_MOVIES":
return {
...state,
movies: state.movies.concat(action.payload)
};
default:
return state;
}
};
File index.js
import React from "react";
import ReactDOM from "react-dom";
import Case from "./app";
import reducer from "./reducer";
import { createStore, applyMiddleware } from "redux";
import { Provider } from "react-redux";
import thunk from "redux-thunk";
let store = createStore(reducer, applyMiddleware(thunk));
ReactDOM.render(
<Provider store={store}>
<Case />
</Provider>,
document.getElementById("container")
);
File index.html
<body>
<div id="container"></div>
</body>

How to dispatch an action and show the data in the app.js using react/redux

I don't know how to load the data of the fetchLatestAnime action in the react app.js file.
My mission is to show the endpoint data that I am doing fetch.
I have already implemented the part of the reducers and action, which you can see in the part below. The only thing I need is to learn how to display the data.
App.js
import React from 'react';
import './App.css';
function App() {
return (
<div className="App">
</div>
);
}
export default App;
actions/types.js
export const FETCHING_ANIME_REQUEST = 'FETCHING_ANIME_REQUEST';
export const FETCHING_ANIME_SUCCESS = 'FETCHING_ANIME_SUCCESS';
export const FETCHING_ANIME_FAILURE = 'FETCHING_ANIME_FAILURE';
actions/animesActions.js
import{
FETCHING_ANIME_FAILURE,
FETCHING_ANIME_REQUEST,
FETCHING_ANIME_SUCCESS
} from './types';
import axios from 'axios';
export const fetchingAnimeRequest = () => ({
type: FETCHING_ANIME_REQUEST
});
export const fetchingAnimeSuccess = (json) => ({
type: FETCHING_ANIME_SUCCESS,
payload: json
});
export const fetchingAnimeFailure = (error) => ({
type: FETCHING_ANIME_FAILURE,
payload: error
});
export const fetchLatestAnime = () =>{
return async dispatch =>{
dispatch(fetchingAnimeRequest());
try{
let res = await axios.get('https://animeflv.chrismichael.now.sh/api/v1/latestAnimeAdded');
let json = await res.data;
dispatch(fetchingAnimeSuccess(json));
}catch(error){
dispatch(fetchingAnimeFailure(error));
}
};
};
reducers/latestAnimeReducers.js
import {
FETCHING_ANIME_FAILURE,
FETCHING_ANIME_REQUEST,
FETCHING_ANIME_SUCCESS
} from '../actions/types';
const initialState = {
isFetching: false,
errorMessage: '',
latestAnime: []
};
const latestAnimeReducer = (state = initialState , action) =>{
switch (action.type){
case FETCHING_ANIME_REQUEST:
return{
...state,
isFetching: true,
}
case FETCHING_ANIME_FAILURE:
return{
...state,
isFetching: false,
errorMessage: action.payload
}
case FETCHING_ANIME_SUCCESS:
return{
...state,
isFetching: false,
latestAnime: action.payload
}
default:
return state;
}
};
export default latestAnimeReducer;
reducers/index.js
import latestAnimeReducers from './latestAnimeReducers'
import {combineReducers} from 'redux';
const reducers = combineReducers({
latestAnimeReducers
});
export default reducers;
index.js
import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import * as serviceWorker from './serviceWorker';
import resolvers from './redux/reducers/index';
import {createStore , applyMiddleware} from 'redux';
import {Provider} from 'react-redux';
import thunk from 'redux-thunk';
const REDUX_DEV_TOOLS = window.__REDUX_DEVTOOLS_EXTENSION__ && window.__REDUX_DEVTOOLS_EXTENSION__()
const createStoreWithMiddleware = applyMiddleware(thunk)(createStore);
const store = createStoreWithMiddleware(resolvers , REDUX_DEV_TOOLS)
ReactDOM.render(
<Provider store={store}>
<App />
</Provider>,
document.getElementById('root')
);
serviceWorker.unregister();

Ideally, this is how your app.js should look like. I created a working codesandbox for you here. Your initial latestAnime state was an empty array but the action payload you set to it is an object, so remember to pass payload.anime like i have done in the sandbox.
import React, { useEffect } from "react";
import { connect } from "react-redux";
import { fetchLatestAnime } from "./redux/actions/animesActions";
const App = props => {
const { fetchLatestAnime, isFetching, latestAnime, errorMessage } = props;
useEffect(() => {
fetchLatestAnime();
}, [fetchLatestAnime]);
console.log(props);
if (isFetching) {
return <p>Loading</p>;
}
if (!isFetching && latestAnime.length === 0) {
return <p>No animes to show</p>;
}
if (!isFetching && errorMessage.length > 0) {
return <p>{errorMessage}</p>;
}
return (
<div>
{latestAnime.map((anime, index) => {
return <p key={index}>{anime.title}</p>;
})}
</div>
);
};
const mapState = state => {
return {
isFetching: state.latestAnimeReducers.isFetching,
latestAnime: state.latestAnimeReducers.latestAnime,
errorMessage: state.latestAnimeReducers.errorMessage
};
};
const mapDispatch = dispatch => {
return {
fetchLatestAnime: () => dispatch(fetchLatestAnime())
};
};
export default connect(
mapState,
mapDispatch
)(App);

Why is my props bringing back the action function, not the date?

I have a react app that is pulling down some data, It turns a promise so I am using Thunk. However when I log this.props, the getShift action prints out as a function.
The log returns:
{getShifts: ƒ}getShifts: ƒ ()proto: Object
Action:
import settings from '../../aws-config.js';
import Amplify, { Auth, API } from 'aws-amplify';
export const GET_STAFF_SHIFTS = 'get_staff_shifts';
export const SHIFTS_LOAD_FAIL = 'shifts_load_fail';
export const getShifts = () => dispatch => {
console.log('Fetching list of shifts for user...');
const request = API.get("StaffAPI", "/shifts", {
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
}
})
.then(response =>
dispatch({
type: 'GET_STAFF_SHIFTS',
payload: response
})
)
.catch(err =>
dispatch({type: 'SHIFTS_LOAD_FAIL'})
)
}
reducer:
import { getShifts, GET_STAFF_SHIFTS} from '../actions';
export default function(state = {}, action) {
switch(action.type){
case GET_STAFF_SHIFTS:
return Object.assign({}, state,{
start_time: action.payload
})
default:
return state;
}
}
Action:
import React, { Component } from 'react';
import Amplify, { Auth, API } from 'aws-amplify';
import {connect} from 'react-redux';
import {bindActionCreators} from 'redux';
import {getShifts} from '../actions/index';
import settings from '../../aws-config.js';
Amplify.configure(settings);
class StaffRota extends Component {
componentWillMount() {
this.props.getShifts();
}
renderPosts(){
console.log(this.props);
return (
<div></div>
);
}
}
function MapDispatchToProps(dispatch) {
return bindActionCreators({ getShifts }, dispatch);
}
export default connect(null, MapDispatchToProps)(StaffRota);

The action creator is supposed to be a function, which is expected. So console logging this.props.getShifts will give you a function.
There are two issues here:
first thing you are dispatching the wrong action type
dispatch({type: 'GET_STAFF_SHIFTS', ... }) instead of dispatch({type: GET_STAFF_SHIFTS, ... }) which you are expecting in your reducer.
secondly you ought to use the redux state via a mapStateToProps function
function MapDispatchToProps(dispatch) {
return bindActionCreators({ getShifts }, dispatch);
}
function MapStateToProps(state) {
return {
shift: state.start_time OR state.your_reducer.start_time
}
}
export default connect(MapStateToProps, MapDispatchToProps)(StaffRota);
And use this state (that is mapped to prop) via this.props.shift.

Redux firing undefined action while using redux thunk

This issue likely stems from a misconfiguration of redux-thunk or a misunderstanding of how to write a thunk. I've tried a lot of different ways, but from what I can tell, this should work. However, I'm still getting a console message that says its firing a redux action of undefined.
Here is my store configuration
import React from 'react';
import ReactDOM from 'react-dom';
import { Provider } from 'react-redux';
import { applyMiddleware, createStore } from 'redux';
import thunk from 'redux-thunk';
import App from './components/App';
import rootReducer from './reducers';
const store = createStore(rootReducer, applyMiddleware(thunk));
ReactDOM.render(
<Provider store={ store }>
<App />
</Provider>,
document.getElementById('rootElement')
);
Here is my action:
import axios from 'axios';
export const GET_ABOUT_CONTENT_REQUEST = 'GET_ABOUT_CONTENT_REQUEST';
export const GET_ABOUT_CONTENT_FAILED = 'GET_ABOUT_CONTENT_FAILED';
export const GET_ABOUT_CONTENT_OK = 'GET_ABOUT_CONTENT_OK';
export const fetchAboutContent = () => {
const url = `http://localhost:3000/about`;
return (dispatch, getState) => {
if (getState.isInitialized === true){
console.log("desktop init should not be called when already desktop is init")
return Promise.resolve();
}
if (getState.about.isLoading) {
console.log('is loading');
return Promise.resolve();
}
dispatch({ type: GET_ABOUT_CONTENT_REQUEST });
axios.get(url)
.then(res => dispatch({
type: GET_ABOUT_CONTENT_OK,
res
}))
.error(err => dispatch({
type: GET_ABOUT_CONTENT_FAILED,
err
}));
}
}
Here is me firing the action in my component:
import React from 'react';
import { connect } from 'react-redux';
import { bindActionCreators } from 'redux';
import * as actions from '../../actions/about';
import getAboutContent from '../../reducers';
class AboutMe extends React.Component {
constructor(props) {
super(props);
}
componentWillMount() {
this.props.getAboutContent();
}
render() {
return <div>{ this.props.content }</div>
}
}
const mapStateToProps = (state) => ({
content: {} || getAboutContent(state)
})
const mapDispatchToProps = (dispatch) =>
bindActionCreators({ getAboutContent }, dispatch)
export default connect(
mapStateToProps, mapDispatchToProps
)(AboutMe);
I've tried quite a few configurations for mapDispatchToProps, i.e. connect(..., { fetchData: getAboutContent })..., and more. Any help is greatly appreciated.
Edit:
Here is the git repo, if that is helpful to anybody: https://github.com/sambigelow44/portfolio-page

Check your reducer name，you export fetchAboutContent, but import getAboutContent.

Code in action file is seems to be incorrect.
getState is a function.
const state = getState();
Change below code.
import axios from 'axios';
export const GET_ABOUT_CONTENT_REQUEST = 'GET_ABOUT_CONTENT_REQUEST';
export const GET_ABOUT_CONTENT_FAILED = 'GET_ABOUT_CONTENT_FAILED';
export const GET_ABOUT_CONTENT_OK = 'GET_ABOUT_CONTENT_OK';
export const fetchAboutContent = () => {
const url = `http://localhost:3000/about`;
return (dispatch, getState) => {
if (getState().isInitialized === true){
console.log("desktop init should not be called when already desktop is init")
return Promise.resolve();
}
if (getState().about.isLoading) {
console.log('is loading');
return Promise.resolve();
}
dispatch({ type: GET_ABOUT_CONTENT_REQUEST });
axios.get(url)
.then(res => dispatch({
type: GET_ABOUT_CONTENT_OK,
res
}))
.error(err => dispatch({
type: GET_ABOUT_CONTENT_FAILED,
err
}));
}
}
Also you need to return promise from axios call, just add return statement.
return axios.get(url)
.then(res => dispatch({
type: GET_ABOUT_CONTENT_OK,
res
}))
.error(err => dispatch({
type: GET_ABOUT_CONTENT_FAILED,
err
}));