I really seem to have trouble with react and hooks. I know that the problem could be do to react-dom. I am watching a tutorial that does it with 5 and im using 6. I looked at the documentation, but I honestly can't find the issue. It worked for my homepage, but now the product page doesn't work and I honestly couldn't find anything on past answers about this problem. Does anybody have an idea?? Thanks!
import React, {useState, useEffect} from 'react'
import { Link } from 'react-router-dom'
import { Row, Col, Image, ListGroup, Button, Card } from 'react-bootstrap'
import Rating from '../components/Rating'
import Loader from '../components/Loader'
import Message from '../components/Message'
import { useParams } from 'react-router-dom'
import { useDispatch, useSelector } from 'react-redux'
import { listProductDetails } from '../actions/productActions'
function ProductScreen({match}) {
const dispatch = useDispatch()
const productDetails = useSelector(state => state.productDetails)
const {loading, error, product} = productDetails
useEffect(() =>{
dispatch(listProductDetails(match.params.id))
},[])
ProductActions.js:
export const listProductDetails = (id) => async(dispatch) => {
try {
dispatch({type: PRODUCT_DETAILS_REQUEST})
const { id } = useParams();
const {data} = await axios.get(`/api/products/${id}`)
dispatch({
type: PRODUCT_DETAILS_SUCCESS,
payload: data
})
} catch (error) {
dispatch({
type: PRODUCT_DETAILS_FAIL,
payload: error.response && error.response.data.message
? error.response.data.message
: error.message,
})
}
}
productReducer.js:
export const productDetailsReducer = (state={product:{reviews:[]}},action) => {
switch(action.type){
case PRODUCT_DETAILS_REQUEST:
return {loading:true, ...state}
case PRODUCT_DETAILS_SUCCESS:
return {loading:false, product:action.payload}
case PRODUCT_DETAILS_FAIL:
return {loading:false, error: action.payload}
default:
return state
}
}
store.js:
import { legacy_createStore as createStore, combineReducers, applyMiddleware } from 'redux'
import thunk from 'redux-thunk'
import { composeWithDevTools } from 'redux-devtools-extension'
import {productListReducer,productDetailsReducer} from './reducers/productReducers'
const reducer = combineReducers({
productList: productListReducer,
productDetails: productDetailsReducer,
})
const initialState = {}
const middleware = [thunk]
const store = createStore(reducer, initialState,
composeWithDevTools(applyMiddleware(...middleware)))
export default store
export const listProductDetails = (id) => async(dispatch) => {
try {
dispatch({type: PRODUCT_DETAILS_REQUEST})
const { id } = useParams();
[...]
You are passing id as argument of listProductDetails then you are redefining it inside the function.
Move const { id } = useParams(); into ProductScreen and pass it as argument to function instead of using match.
Also listProductDetails returns an async function that takes dispatch as argument. So don't call dispatch(listProductDetails(id)) but instead call listProductDetails(id)(dispatch).
Also calling dispatch within the api is not a good idea. You generally want action function to return something to be dispatched within a React Component.
function ProductScreen() {
const dispatch = useDispatch();
const { id } = useParams();
const productDetails = useSelector((state) => state.productDetails);
const { loading, error, product } = productDetails;
useEffect(() => {
const fetchData = async (id) => {
dispatch({ type: PRODUCT_DETAILS_REQUEST });
dispatch(await listProductDetails(id));
};
fetchData(id);
}, [dispatch, id]);
return <div>APP</div>;
}
In ProductActions.js
export const listProductDetails = async (id) => {
try {
const { data } = await axios.get(`/api/products/${id}`);
return {
type: PRODUCT_DETAILS_SUCCESS,
payload: data,
};
} catch (error) {
return {
type: PRODUCT_DETAILS_FAIL,
payload:
error.response && error.response.data.message
? error.response.data.message
: error.message,
};
}
};
Related
I got following error at onAuthStateChanged method at store.dispatch(userActions.setUser(null));
Error: [Immer] produce can only be called on things that are draftable: plain objects, arrays, Map, Set or classes that are marked with '[immerable]: true'. Got '[object Object]'
I am trying to change to firebase authentication from jwt. So custom jwt authentication is using redux. Now when I call firebase's signOut(auth) method, onAuthStateChanged method give me this error. May I know how to write immerable object for user.
user_reducer.js
import produce from "immer";
import * as Action_Constants from "../actions/user_actions";
const initialState = null;
export const UserReducer = produce((state = initialState, action) => {
switch (action.type) {
case Action_Constants.SET_USER: {
return action.user;
}
case Action_Constants.FETCH_USER_COMPLETED: {
return action.user;
}
default:
return state;
}
});
user_actions.js
export const FETCH_USER = "FETCH_USER";
export const FETCH_USER_COMPLETED = "FETCH_USER_COMPLETED";
export const SET_USER = "SET_USER";
export const actionCreators = {
fetchUser: (id) => ({
type: FETCH_USER,
id,
}),
fetchUserCompleted: (user) => ({
type: FETCH_USER_COMPLETED,
user,
}),
setUser: (user) => ({
type: SET_USER,
user,
}),
};
I have deleted other firebase functions to simply the file.
auth_provider.jsx
import React, { useState, useEffect, useContext, createContext } from "react";
import { useLocation, Navigate } from "react-router-dom";
import { signIn, signUp } from "../helpers/gql_auth_helpers";
import paths from "../routes/paths";
import { store } from "../store/configure_store";
import { actionCreators as userActions } from "../store/actions/user_actions";
import { auth } from "../helpers/init-firebase";
import {
onAuthStateChanged,
signOut,
} from "firebase/auth";
const AuthContext = createContext(null);
let accessToken = "";
export const getAccessToken = () => accessToken;
export const setAccessToken = (token) => {
accessToken = token;
};
export const AuthProvider = ({ user: usr, children }) => {
const [user, setUser] = useState(usr);
useEffect(() => {
const unsubscribe = onAuthStateChanged(auth, (user) => {
if (user) {
setUser(user);
setAccessToken(user.getIdToken(true));
store.dispatch(userActions.setUser(user));
} else {
setUser(null);
setAccessToken(null);
store.dispatch(userActions.setUser(null));
}
});
return () => {
unsubscribe();
};
}, []);
async function logout() {
return signOut(auth);
}
const value = {
user,
accessToken,
logout,
};
return <AuthContext.Provider value={value}>{children}</AuthContext.Provider>;
};
export const useAuth = () => {
return useContext(AuthContext);
};
Getting a weird error where 'map' is undefined. I'm not sure if my functions are firing at the wrong time and that's resulting in no data being received.
I'm adding Redux into my simple little application that just pulls data from an API and displays it. It's a list of a bunch of Heroes. Like I said before, I think that the error is coming from different times in the ansyc API call and when Redux is firing. But then again I'm a novice so any help is much appreciated.
import React, {useEffect} from 'react'
import { connect } from 'react-redux'
import { fetchHeroes } from '../actions/heroesActions'
import { Hero } from '../components/Hero'
const HeroesPage = ({ dispatch, loading, heroes, hasErrors }) => {
useEffect(() => {
dispatch(fetchHeroes())
}, [dispatch])
const renderHeroes = () => {
if (loading) return <p>Loading posts...</p>
if (hasErrors) return <p>Unable to display posts.</p>
return heroes.map(hero => <Hero key={hero.id} hero={hero} />)
}
return (
<section>
<h1>Heroes</h1>
{renderHeroes()}
</section>
)
}
// Map Redux state to React component props
const mapStateToProps = state => ({
loading: state.heroes.loading,
heroes: state.heroes.heroes,
hasErrors: state.heroes.hasErrors,
})
export default connect(mapStateToProps)(HeroesPage)
export const GET_HEROES = 'GET HEROES'
export const GET_HEROES_SUCCESS = 'GET_HEROES_SUCCESS'
export const GET_HEROES_FAILURE = 'GET_HEROES_FAILURE'
export const getHeroes = () => ({
type: GET_HEROES,
})
export const getHeroesSuccess = heroes => ({
type: GET_HEROES_SUCCESS,
payload: heroes,
})
export const getHeroesFailure = () => ({
type: GET_HEROES_FAILURE,
})
export function fetchHeroes() {
return async dispatch => {
dispatch(getHeroes())
try {
const response = await fetch('https://api.opendota.com/api/heroStats')
console.log(response)
const data = await response.json()
dispatch(getHeroesSuccess(data))
} catch (error) {
dispatch(getHeroesFailure())
}
}
}
index.js where I created the store
// External imports
import React from 'react'
import { render } from 'react-dom'
import { createStore, applyMiddleware } from 'redux'
import { Provider } from 'react-redux'
import thunk from 'redux-thunk'
import { composeWithDevTools } from 'redux-devtools-extension'
// Local imports
import App from './App'
import rootReducer from './reducers'
const store = createStore(rootReducer, composeWithDevTools(applyMiddleware(thunk)))
render(
<Provider store={store}>
<App />
</Provider>,
document.getElementById('root')
)
import React, {useEffect} from 'react'
import { useSelector } from 'react-redux'
import { fetchHeroes } from '../actions/heroesActions'
import { Hero } from '../components/Hero'
const HeroesPage = () => {
const data = useSelector(state => state.heroes);
useEffect(() => {
fetchHeroes();
}, [])
const renderHeroes = () => {
if (data.loading) return <p>Loading posts...</p>
if (data.hasErrors) return <p>Unable to display posts.</p>
return data.heroes.map(hero => <Hero key={hero.id} hero={hero} />)
}
return (
<section>
<h1>Heroes</h1>
{renderHeroes()}
</section>
)
}
export default HeroesPage
action file
// import store from your createStore file and access dispatch from it
dispatch = store.dispatch
export const GET_HEROES = 'GET HEROES'
export const GET_HEROES_SUCCESS = 'GET_HEROES_SUCCESS'
export const GET_HEROES_FAILURE = 'GET_HEROES_FAILURE'
export const getHeroes = () => ({
type: GET_HEROES,
})
export const getHeroesSuccess = heroes => ({
type: GET_HEROES_SUCCESS,
payload: heroes,
})
export const getHeroesFailure = () => ({
type: GET_HEROES_FAILURE,
})
export const fetchHeroes = () => {
dispatch(getHeroes())
try {
const response = await fetch('https://api.opendota.com/api/heroStats')
console.log(response)
const data = await response.json()
dispatch(getHeroesSuccess(data))
} catch (error) {
dispatch(getHeroesFailure())
}
}
reducer file
import * as actions from '../actions/heroesActions'
export const initialState = {
heroes: [],
loading: false,
hasErrors: false,
}
export default function heroesReducer(state = initialState, action) {
switch (action.type) {
case actions.GET_HEROES:
return { ...state, loading: true }
case actions.GET_HEROES_SUCCESS:
return { heroes: action.payload, loading: false, hasErrors: false }
case actions.GET_HEROES_FAILURE:
return { ...state, loading: false, hasErrors: true }
default:
return state
}
}
Need help, just started to learn React. I'm trying to pass variables with json data to a component for further use, but catching the errors. what should I change to use variables with json() data from Store.js in the product.js component? THanks for your time!
https://jsfiddle.net/constant101/xu7zdn26/3/ for better visibility
//Store export(receiving data from the server and assigning them to variables)
import React, {useState, useEffect} from 'react'
import axios from 'axios'
export const ListContext = React.createContext([]);
export const ItemContext = React.createContext([]);
function Store() {
const [storeProducts, setStoreProducts] = useState([]);
const [detailProduct, setDetailProduct] = useState([]);
useEffect(() => {
axios.get('/products/')
.then(res => {
console.log(res)
setStoreProducts(res.data)
})
},[])
console.log('storeProducts:', storeProducts)
useEffect(() => {
axios.get('/products/:productId')
.then(res => {
console.log(res)
setDetailProduct(res.data)
})
},[])
console.log('detail product:', detailProduct)
return (
<ListContext.Provider value={[storeProducts, setStoreProducts]}>
<ItemContext.Provider value={[detailProduct, setDetailProduct]}>
<product/>
</ItemContext.Provider>
</ListContext.Provider>
);
}
export const detailProduct
//product.js ( file that uses data from the fetch)
import React, { useReducer, createContext, useContext, useState } from 'react';
import {ListContext, ItemContext } from '../Store';
import { useProductActions } from '../actions';
import { SET_PRODUCT_DETAILS } from '../actions/types';
const [storeProducts] = useContext(ListContext);
const [detailProduct] = useContext(ItemContext);
let tempProducts = [];
storeProducts.forEach(item => tempProducts.push({ ...item })
);
const initialState = {
products: tempProducts,
productDetails: { ...detailProduct }
};
console.log(storeProducts)
const productReducer = (state, action) => {
switch (action.type) {
case SET_PRODUCT_DETAILS:
return {
...state,
productDetails: action.payload
};
default:
throw new Error('Invalid action type');
}
};
export const ProductContext = createContext(initialState);
export const useProductState = () => {
return useContext(ProductContext);
};
export const ProductProvider = ({ children }) => {
const [state, dispatch] = useReducer(productReducer, initialState);
const productActions = useProductActions(state, dispatch);
return (
<ProductContext.Provider value={{ productState: state, productActions }}>
{children}
</ProductContext.Provider>
);
};
Well, assuming your request is right, i saw a syntax mistake. You should pass
<ListContext.Provider value={{storeProducts, setStoreProducts}}> instead of
<ListContext.Provider value={[storeProducts, setStoreProducts]}>
The reason:
a provider requires a prop called value with an Object inside.
In that case, you were passing an array.
it would be the same if you did:
<ListContext.Provider
value={{
storeProducts: storeProducts,
setStoreProducts: setStoreProducts
}}
>
but to follow the DRY principle, it's recommended to do that way described earlier
Ive been trying to do this with react hooks and the useSelector/useDispatch. What happens is, I am able to see the data and state change in the Redux DevTools however, when logging to the console, I either get an empty array or undefined. I am also not able to render the data to the screen expectedly.
Posts Component
import React, {useState, useEffect} from 'react'
import PropTypes from 'prop-types'
import {useSelector, useDispatch} from 'react-redux'
import {getPosts} from '../actions/postActions'
const Posts = props =>{
const dispatch = useDispatch();
const postData = useSelector(state=> state.items, []) || []; //memoization?
const [items, setItems] = useState(postData)
console.log(postData);
useEffect(() => {
dispatch(getPosts());
}, []);
return(
<h1>{postData[0]}</h1>
)
}
export default Posts
ACTIONS
import {GET_POSTS, NEW_POSTS} from '../actions/types'
export const getPosts =()=> dispatch =>{
//fetch
console.log('fetching')
const url = 'https://jsonplaceholder.typicode.com/posts/'
fetch(url)
.then(res => res.json())
.then(posts=> dispatch({type: GET_POSTS, payload: posts}))
}
reduxDevTools image
I think the problem is coming from this line:
const postData = useSelector(state=> state.items, []) || [];
If you want postData to initially be an array, it's best to set it as an array in your reducer.
Working example (click Posts tab to make API call):
actions/postActions.js
import api from "../utils/api";
import * as types from "../types";
export const getPosts = () => async dispatch => {
try {
dispatch({ type: types.POSTS_FETCH });
const res = await api.get("posts");
dispatch({
type: types.POSTS_SET,
payload: res.data
});
} catch (err) {
dispatch({
type: types.POSTS_FAILED_FETCH,
payload: err.toString()
});
}
};
reducers/postsReducer.js
import * as types from "../types";
const initialState = {
data: [],
error: "",
isLoading: true
};
export default (state = initialState, { type, payload }) => {
switch (type) {
case types.POSTS_FETCH:
return initialState;
case types.POSTS_SET:
return {
...state,
data: payload,
error: "",
isLoading: false
};
case types.POSTS_FAILED_FETCH:
return {
...state,
error: payload,
isLoading: false
};
default:
return state;
}
};
containers/FetchPostsHooks/index.js
import React, { useEffect } from "react";
import { useSelector, useDispatch } from "react-redux";
import { getPosts } from "../../actions/postActions";
import Spinner from "../../components/Spinner";
import DisplayPosts from "../../components/DisplayPosts";
const Posts = () => {
const dispatch = useDispatch();
const { isLoading, data, error } = useSelector(state => state.posts, []);
useEffect(() => {
dispatch(getPosts());
}, [dispatch]);
return isLoading ? (
<Spinner />
) : error ? (
<p>{error}</p>
) : (
<DisplayPosts data={data} />
);
};
export default Posts;
I am trying to fetch data from an api, but I am getting an error: TypeError: this.props.getPeople is not a function, while everything looks good through the code, as below:
people-component.js
import React, { Component } from 'react';
import './people-component-styles.css';
import { Container, Row, Col, Card } from 'react-bootstrap';
import { connect } from 'react-redux';
import { getPeople } from '../../actions/index'
import 'react-lazy-load-image-component/src/effects/blur.css';
import 'animate.css/animate.min.css';
export class People extends Component {
componentDidMount() {
// console.log(this.props);
this.props.getPeople();
}
render() {
// console.log(this.props);
return (
<Row className='main'>
hello!
</Row>
);
}
}
const mapStateToProps = state => ({
people: state.people
})
const mapDispatchToProps = dispatch => ({
getPeople: () => dispatch(getPeople())
})
export default connect(
mapStateToProps,
mapDispatchToProps
)(People);
actions/index.js
export const getPeople = () => {
console.log("yes");
return async dispatch => {
const response = await fetch('https://dma.com.eg/api.php?action=getPeople', {
method: 'GET'
})
const json = await response.json();
dispatch({ type: "GET_PEOPLE", payload: json });
}
}
reducers/index.js
const INITIAL_STATE = {
people: []
}
const rootReducer = (state = INITIAL_STATE, action) => {
switch (action.type) {
case "GET_PEOPLE":
return ({
...state,
people: state.people.concat(action.payload)
})
default:
return state;
}
};
export default rootReducer
I was importing People component as name while it's exported as default, thanks to #Brian Thompson .. it's fixed.