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Dispatching multiple actions in redux duplicates the state parameters

I have used created two actions and their respective reducers. When i dispatch any single action, both actions initial states are being saved to state where the parameters of the states are duplicated.
actions/index.js
import { COUNTER_CHANGE, UPDATE_NAVIGATION } from "../constants";
export function changeCount(count) {
return {
type: COUNTER_CHANGE,
payload: count,
};
}
export function updateNavigation(obj) {
return {
type: UPDATE_NAVIGATION,
payload: obj,
};
}
reducers.js
import { COUNTER_CHANGE, UPDATE_NAVIGATION } from "../constants";
import logger from "redux-logger";
const initialState = {
count: 0,
navigation: {},
};
export const countReducer = (state = initialState, action) => {
switch (action.type) {
case COUNTER_CHANGE:
return {
...state,
count: action.payload,
};
default:
return state;
}
};
export const updateNavigation = (state = initialState, action) => {
switch (action.type) {
case UPDATE_NAVIGATION:
return {
...state,
navigation: action.payload,
};
default:
return state;
}
};
// export default countReducer;
reducer/index.js
import { countReducer, updateNavigation } from "../reducers/countReducer";
import { combineReducers } from "redux";
const allReducers = combineReducers({
countReducer,
updateNavigation,
});
export default allReducers;
Dispatching actions
componentDidMount = () => {
const { navigation } = this.props;
this.props.updateNavigation(navigation);
};
const mapDispatchToProps = (dispatch) => {
return { ...bindActionCreators({ changeCount, updateNavigation }, dispatch) };
};
As we can see here I have triggered only updateNavigation action. But it updates states with duplicate parameters in redux state as shown below
The expected o/p will be
countReducer : {count : 0}
updateNavigation : {navigation :{}}

The shape of state for each reducer is incorrect. See defining-state-shape docs and try this:
export const countReducer = (state = { count: 0 }, action) => {
switch (action.type) {
case COUNTER_CHANGE:
return {
...state,
count: action.payload,
};
default:
return state;
}
};
export const updateNavigation = (state = { navigation: {} }, action) => {
switch (action.type) {
case UPDATE_NAVIGATION:
return {
...state,
navigation: action.payload,
};
default:
return state;
}
};
import { countReducer, updateNavigation } from "../reducers/countReducer";
import { combineReducers } from "redux";
const allReducers = combineReducers({
countReducer,
updateNavigation,
});
const store = createStore(allReducers);
console.log(store.getState());
Output:
{ countReducer: { count: 0 }, updateNavigation: { navigation: {} } }

In your action/index.js
import { COUNTER_CHANGE, UPDATE_NAVIGATION } from "../constants";
export function changeCount(count) {
dispatch( {
type: COUNTER_CHANGE,
payload: count,
});
}
export function updateNavigation(obj) {
dispatch({
type: UPDATE_NAVIGATION,
payload: obj,
});
}
Dispatch the data without returning it

React redux prop object property undefined

I am new to React Redux. I am not sure what is wrong on my code. There is no error on the terminal but when I take a look on the browser there is a TypeError. ItemsProduct was on the props. I was wondering why it returns an error when I am trying to access the properties.
productDescription.js
import React, { Component } from "react";
import { Link } from "react-router-dom";
import { connect } from "react-redux";
import axios from "axios";
import {
fetchProductsRequests,
fetchProductsSuccess,
fetchProductError,
} from "../../actions/productActions";
class ProductDescription extends Component {
componentDidMount() {
this.props.fetchProducts();
}
render() {
return (
<>
<div className="grid grid-cols-3 gap-6 mb-10">
<div className="col-start-2 col-end-4">
<h4>{this.props.itemsProduct[0].name}</h4>
</div>
</div>
</>
);
}
}
const mapStateToProps = (state, ownProps) => {
return {
itemsProduct: state.rootProduct.products.filter(
(prod) => prod.id == ownProps.match.params.id
),
};
};
const mapDispatchToProps = (dispatch) => {
return {
fetchProducts: () => {
dispatch(fetchProductsRequests());
axios
.get("http://localhost:3000/js/products.json")
.then((response) => {
dispatch(fetchProductsSuccess(response.data));
})
.catch((error) => {
dispatch(fetchProductError(error.message));
});
},
};
};
export default connect(mapStateToProps, mapDispatchToProps)(ProductDescription);
productActions.js
export const FETCH_PRODUCTS_REQUESTS = "FETCH_PRODUCTS_REQUESTS";
export const FETCH_PRODUCTS_SUCCESS = "FETCH_PRODUCTS_SUCCESS";
export const FETCH_PRODUCTS_ERROR = "FETCH_PRODUCTS_ERROR";
export const fetchProductsRequests = () => {
return {
type: FETCH_PRODUCTS_REQUESTS,
};
};
export const fetchProductsSuccess = (product) => {
return {
type: FETCH_PRODUCTS_SUCCESS,
payload: product,
};
};
export const fetchProductError = (error) => {
return {
type: FETCH_PRODUCTS_ERROR,
payload: error,
};
};
productReducer.js
const initialState = {
loading: true,
products: [],
error: "",
};
const productReducer = (state = initialState, action) => {
switch (action.type) {
case "FETCH_PRODUCTS_REQUESTS":
return {
...state,
loading: true,
};
case "FETCH_PRODUCTS_SUCCESS":
return {
loading: false,
products: action.payload,
error: "",
};
case "FETCH_PRODUCTS_ERROR":
return {
loading: false,
products: [],
error: action.payload,
};
default:
return state;
}
};
export default productReducer;
Root Reducer
import { combineReducers } from "redux";
import productReducer from "./productReducer";
const rootReducer = combineReducers({
rootProduct: productReducer,
});
export default rootReducer;

You can do a quick check if there is data coming from your axios by doing this (it will prevent any undefined or null values)
dispatch(fetchProductsSuccess(response.data || 'no data'));
Also you should return your state in the reducer as follows:
case "FETCH_PRODUCTS_SUCCESS":
return {
...state,
loading: false,
products: action.payload,
error: "",
};
case "FETCH_PRODUCTS_ERROR":
return {
...state,
loading: false,
products: [],
error: action.payload,
};
Your
itemsProduct: state.rootProduct.products.filter(
(prod) => prod.id == ownProps.match.params.id
),
may return an empty array meaning you will not be able to retrieve that object in your view
<h4>{this.props.itemsProduct[0].name}</h4>

React-Redux - TypeError: state.menu is not iterable

I am working on a React application and I am using Redux to store the state. I have the following code:
menu.reducer.js:
import { INCREASE_CATEGORY_RANK, DECREASE_CATEGORY_RANK } from './menu.types';
const INITIAL_STATE = []
export default (state = INITIAL_STATE, action) => {
switch (action.type) {
case INCREASE_CATEGORY_RANK: {
console.log("Printing state");
console.log(state);
const menuArray = [...state.menu];
menuArray.sort((a,b) => (a.rank > b.rank) ? 1 : -1);
return {
...state,
menu: menuArray
}
}
case DECREASE_CATEGORY_RANK: {
return state.map(category => {
if (category._id === action.payload._id && category.rank !== -1) {
const oldrank = category.rank;
return {
...category,
rank: oldrank - 1
}
} else {
return category;
}
})
}
default:
return state;
}
}
menu.types.js:
export const INCREASE_CATEGORY_RANK = "INCREASE_CATEGORY_RANK";
export const DECREASE_CATEGORY_RANK = "DECREASE_CATEGORY_RANK";
menu.actions.js:
import { apiUrl, apiConfig } from '../../util/api';
import { INCREASE_CATEGORY_RANK, DECREASE_CATEGORY_RANK } from './menu.types';
export const getMenu = () => async dispatch => {
const response = await fetch(`${apiUrl}/menu`);
if (response.ok) {
const menuData = await response.json();
dispatch({ type: GET_MENU, payload: menuData })
}
}
export const increaseCategoryRank = category => dispatch => {
dispatch({ type: INCREASE_CATEGORY_RANK, payload: category })
}
export const decreaseCategoryRank = category => dispatch => {
dispatch({ type: DECREASE_CATEGORY_RANK, payload: category })
}
category-arrows.component.jsx:
import React, { Component } from 'react';
import { connect } from 'react-redux';
import { increaseCategoryRank, decreaseCategoryRank } from '../../redux/menu/menu.actions';
import './category-arrows.styles.scss';
class CategoryArrows extends Component {
render() {
const { category, increaseCategoryRank, decreaseCategoryRank } = this.props;
return (
<div class="arrows-container">
<div class="up-arrow" onClick={() => this.props.increaseCategoryRank(category)}></div>
<div class="category-rank">
<p>{category.rank}</p>
</div>
<div class="down-arrow" onClick={() => this.props.decreaseCategoryRank(category)}></div>
</div>
)
}
}
export default connect(null, { increaseCategoryRank, decreaseCategoryRank } )(CategoryArrows);
For my Reducer function, the initial state is retrieved from a database. The Reducer code deals with the menu array, which is an array of objects:
I want to copy the menu array from the state in my Reducer function, so that I can sort it, and then reassign the sorted menu array to the state.
I have tried to console.log() the state to see what it is in my Reducer function. When I click on the up-arrow div in category-arrows.component.jsx, the INCREASE_CATEGORY_RANK action is dispatched. When I check the Console, I get the following:
However when I copy the menu array from the state in the INCREASE_CATEGORY_RANK case in my Reducer function, I get the following error:
I am not sure why I am getting the above error and how to resolve it. Any insights are appreciated.

It looks like the reducer expect an array not an object:
export default (state = INITIAL_STATE, action) => {
switch (action.type) {
case INCREASE_CATEGORY_RANK: {
return [...state].sort((a,b) => (a.rank > b.rank) ? 1 : -1);
}
}
}

Getting TypeError: _this2.props.handleClick is not a function when passing redux prop from container to presentational component in react

Pretty new to Redux. I'm trying to pass a handleClick event as a prop from a container component to a presentational component, the handleClick event is supposed to call upon an action which has been received as a prop with mapDispatchToProps.
Could someone tell me how to do this correctly please?
I'm building a calculator, just started, this only has three actions so far, add, Record_input_1 and Record_Input_2.
containers/ButtonsContainer.js:
import React, { Component } from 'react';
import { Buttons } from '../components/Buttons'
import { Record_Input_1 } from '../actions/sum-action';
import { connect } from 'react-redux';
import { bindActionCreators } from 'redux';
class ButtonsContainer extends Component {
constructor(props) {
super(props);
this.handleClick = this.handleClick.bind(this);
}
handleClick(num) {
return this.props.onRecordInput1(num)
}
render() {
return(
<Buttons handleClick={this.handleClick} />
)
}
mapStateToProps = (state) => {
return {
inputValue1: state.inputValue1,
inputValue2: state.inputValue2,
answer: state.answer
}
}
mapDispatchToProps = (dispatch) => {
return bindActionCreators({
onRecordInput1: Record_Input_1,
onRecordInput2: Record_Input_2
}, dispatch);
}
}
export default connect(mapStateToProps, mapDispatchToProps)(ButtonsContainer);
components/Buttons.js
import React, { Component } from 'react';
class Buttons extends Component {
render() {
const buttonMaker = (buttons, row) => {
for (let value of buttons) {
row.push(<button onClick={() => this.props.handleClick(value)} key={value}>
{value}
</button> )
}
}
let row1 = [];
let buttons1 = [1,2,3]
buttonMaker(buttons1, row1)
let row2 = [];
let buttons2 = [4,5,6]
buttonMaker(buttons2, row2)
let row3 = [];
let buttons3 = [7,8,9]
buttonMaker(buttons3, row3)
return (
<div>
<div>{row1}</div>
<br />
<div>{row2}</div>
<br />
<div>{row3}</div>
</div>
)
}
}
export default Buttons;
actions/sum-actions/js:
export const ADD = 'ADD';
export const RECORD_INPUT_1 = 'RECORD_INPUT_1';
export const RECORD_INPUT_2 = 'RECORD_INPUT_2';
export const add = (newInput1, newInput2) => {
return {
type: ADD,
newAnswer: newInput1 + newInput2
}
}
export const Record_Input_1 = (newInput1) => {
return {
type: RECORD_INPUT_1,
newInput1
}
}
export const Record_Input_2 = (newInput2) => {
return {
type: RECORD_INPUT_2,
newInput2
}
}
reducders/sum-reducer.js:
import { ADD, RECORD_INPUT_1, RECORD_INPUT_2 } from '../actions/sum-action'
export const initialState = {
inputValue1: '',
inputValue2: '',
answer: 0
}
export const sumReducer = (state = initialState, action) => {
switch (action.type) {
case ADD:
return [
...state,
{
answer: action.newAnswer
}
]
case RECORD_INPUT_1:
return [
...state,
{
inputValue1: action.newInput1
}
]
case RECORD_INPUT_2:
return [
...state,
{
inputValue2: action.newInput2
}
]
default:
return state;
}
}
store.js:
import { combineReducers, createStore } from 'redux';
import { initialState, sumReducer } from './reducers/sum-reducer';
const rootReducers = combineReducers({
sumReducer
})
export default createStore(rootReducers, initialState, window.devToolsExtension && window.devToolsExtension());
The buttons display ok, when I click on one I get this error:
TypeError: _this2.props.handleClick is not a function
for:
8 | render() {
9 | const buttonMaker = (buttons, row) => {
10 | for (let value of buttons) {
> 11 | row.push(<button onClick={() => this.props.handleClick(value)} key={value}
12 | {value}
13 | </button> )
14 | }

You are declaring mapStateToProps and mapDispatchToProps within ButtonsContainer. You are then passing those two methods to react-redux's connect as if they were declared outside of ButtonsContainer, hence they are undefined. Try moving them out of ButtonsContainer as shown here. It should look something like this:
class ButtonsContainer extends Component {
...
}
const mapStateToProps = (state) => {
return {
inputValue1: state.inputValue1,
inputValue2: state.inputValue2,
answer: state.answer
}
}
const mapDispatchToProps = (dispatch) => {
return bindActionCreators({
onRecordInput1: Record_Input_1,
onRecordInput2: Record_Input_2
}, dispatch);
}
export default connect(mapStateToProps, mapDispatchToProps)(ButtonsContainer);

How to dispatch two actions (one is async), in redux-thunk?

Dispatch multiple actions in redux-thunk and receive infinite loop.
I am trying to turn on a spinner before a request goes to the back-end and stop spinner after request succeeds or fails.
Does anyone have any idea about where I've done mistake?
My code looks like this.
logic.js
import * as actions from "./actions";
export const getData = () => {
return dispatch => {
dispatch(actions.startSpinner());
setAuthorizationToken(getToken());
axiosInstance
.get("/data")
.then(response => {
dispatch(actions.stopSpinner()); //I guess this is problem ?
dispatch(actions.getData(response.data));
})
.catch(err => {
console.log(err);
dispatch(actions.stopSpinner());
});
};
};
And file actions.js
export const startSpinner = () => {
return { type: actionTypes.START_SPINNER };
};
export const stopSpinner = () => {
return { type: actionTypes.STOP_SPINNER };
};
export const getData = data => {
return {
type: actionTypes.GET_DATA,
payload: data
};
};
And reducer for it spinner.js
import actionTypes from "../actionTypes";
export default (state = false, action) => {
switch (action.type) {
case actionTypes.START_SPINNER: {
return (state = true);
}
case actionTypes.STOP_SPINNER: {
return (state = false);
}
default: {
return state;
}
}
};
And reducer for data dataReducer.js
import actionTypes from "../actionTypes";
const defaultState = [];
export default (state = defaultState, action) => {
switch (action.type) {
case actionTypes.GET_DATA: {
let newState = [...action.payload];
return newState;
}
default: {
return state;
}
}
};