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controlled range-slider component in react with redux

i am learning redux with react and trying to create an app where i have a range-slider, whose value dictates how many Box components will be rendered on the screen.
i am trying to make the range-slider a controlled component but can't make it change the store. i am getting no errors.
the component:
import React from 'react';
import { connect } from 'react-redux';
import { setBoxNumber } from '../actions/actions';
const Slider = ({ boxNumber, handleChange }) => {
return(
<div>
<div>
{boxNumber}
</div>
<div>
<input
onChange={handleChange}
value={boxNumber}
type="range"
min="12"
max="480"
/>
</div>
</div>
)
}
const mapStateToProps = (state) => {
return { boxNumber: state.boxNumber }
}
const mapDispatchToProps = (dispatch) => {
return {
handleChange: (event) => dispatch(setBoxNumber(event.target.value))
}
}
export default connect(mapStateToProps, mapDispatchToProps)(Slider);
the reducer:
import { combineReducers } from 'redux';
export const boxNumberReducer = (boxNumber = 40, action) => {
switch(action.payload) {
case 'SET_BOX_NUMBER':
return action.payload;
default:
return boxNumber;
}
}
export default combineReducers({
boxNumber: boxNumberReducer
})
the action:
export const setBoxNumber = (number) => {
return {
type: 'SET_BOX_NUMBER',
payload: number
}
}
i also tried to call the handleChange method with an arrow function on change, like i would do with a controlled react component without redux, but it's making no difference

I think your reducer is configured incorrectly. You can pass all the initial states inside the variable initialState like this.
//reducer.js
import { combineReducers } from "redux";
const initialState = {
boxNumber: 40,
};
const boxReducer = (state = initialState, action) => {
switch (action.type) {
case "SET_BOX_NUMBER":
return {
...state,
boxNumber: action.payload,
};
default:
return state;
}
};
export default combineReducers({
boxReducer,
});
This is how your index.js file should look like:
//index.js
import React from "react";
import ReactDOM from "react-dom";
import Slider from "./Slider.js";
import { Provider } from "react-redux";
import { createStore } from "redux";
import reducer from "./redux/reducer";
const store = createStore(reducer);
ReactDOM.render(
<Provider store={store}>
<Slider />
</Provider>,
document.getElementById("root")
);
You need to update your mapStateToProps in Slider.js to access the states in your reducer.
//Slider.js
const mapStateToProps = (state) => {
return { boxNumber: state.boxReducer.boxNumber };
};
This is a simple fix. As your app gets bigger, you'll need more reducers and thus it's better to keep a separate file for that.

Redux and Axios get. method not returning any data

Need some help.
As I am trying to get some understanding of React/REdux global state I made some simple get request.
This is done with Axios, thunk, Redux, but i can't get this working
I have Post.js file, nothing fancy
import React, { Component } from 'react';
import PropTypes from 'prop-types';
import PostForm from './PostForm';
export class Post extends Component {
static propTypes = {
posts: PropTypes.any,
fetchPosts: PropTypes.func,
};
componentDidMount() {
const { fetchPosts } = this.props;
fetchPosts();
}
render() {
const { posts } = this.props;
return (
<div>
<PostForm addPost={this.onSubmit} />
<br />
<div>
{posts.map(post => (
<div key={post.id}>
<h3>{post.title}</h3>
<p>{post.body}</p>
</div>
))}
</div>
</div>
);
}
}
export default Post;
Next i have my PostContainer.js
import { connect } from 'react-redux';
import Post from './Post';
import { fetchFromApi } from '../reducers/postReducers';
const mapStateToProps = state => ({
posts: state.posts,
});
const mapDispatchToProps = dispatch => ({
fetchPosts: () => dispatch(fetchFromApi()),
});
export default connect(mapStateToProps, mapDispatchToProps)(Post);
My reducer
import Axios from 'axios';
/* action type */
const FETCH_POSTS = 'FETCH_POSTS';
/* action creator */
export const fetchStarted = payload => ({ payload, type: FETCH_POSTS });
/* thunk */
export const fetchFromApi = () => {
return (dispatch, getState) => {
Axios.get('https://jsonplaceholder.typicode.com/posts?_limit=5').then(res =>
dispatch(fetchStarted(res.data))
);
};
};
/* reducer */
export default function reducer(state = [], action = {}) {
switch (action.type) {
case FETCH_POSTS: {
return {
...state,
data: action.payload,
};
}
default:
return state;
}
}
and my store
import { combineReducers, applyMiddleware, createStore } from 'redux';
import thunk from 'redux-thunk';
import { composeWithDevTools } from 'redux-devtools-extension';
import postReducer from './reducers/postReducers';
const initialState = {
posts: {
data: {},
},
};
const reducers = {
posts: postReducer,
};
Object.keys(initialState).forEach(item => {
if (typeof reducers[item] == 'undefined') {
reducers[item] = (state = null) => state;
}
});
const combinedReducers = combineReducers(reducers);
const store = createStore(
combinedReducers,
initialState,
composeWithDevTools(applyMiddleware(thunk))
);
export default store;
All of that is doing not much. My map method is trying to map empty posts object. And for some reason my fetchPosts is not dispatched. I have reade some old posts here but still can't get this working
Thanks
Edit
this is my app.js file with container
import React from 'react';
import './App.css';
import Post from './components/PostContainer';
import { Provider } from 'react-redux';
import store from './store';
function App() {
return (
<Provider store={store}>
<div className='App'>
<Post />
</div>
</Provider>
);
}
export default App;

I managed to get this working.
Data was not there when my posts array was render. After passing simple if statemante all is working

redux-saga takeEvery only called when you click on btn, componentDidMount doesn`t call action correct

Sory for my English!
I am doing test work on React.js. The task is to make a regular blog. I ran into an unwanted problem. As a rule, componentDidMount makes entries, ready data and is called once.
I invoke the loadPosts action in the CDM to get the data.
The takeEvery effect sees the necessary saga, but does not cause it, but skips it.
When I press a button, everything works fine.
I'm new to React. All i tried is google
repository with project
branch - dev-fullapp
index.js
import store from "./redux/store";
const app = (
<BrowserRouter>
<Provider store={store}>
<App />
</Provider>
</BrowserRouter>
);
store.js
import { createStore, compose, applyMiddleware } from "redux";
import createSagaMiddleware from "redux-saga";
import apiSaga from "./sagas/index";
import rootReducer from "./reducers/index";
const initialiseSagaMiddleware = createSagaMiddleware();
const storeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;
const store = createStore(
rootReducer,
storeEnhancers(applyMiddleware(initialiseSagaMiddleware))
);
initialiseSagaMiddleware.run(apiSaga);
export default store;
sagas.js
import { put, call, takeEvery } from "redux-saga/effects";
import { fetchGetPosts } from "../apis/index";
import { setErrorPosts, setPosts } from "../actions/actions-posts";
function* workerGetPosts() {
try {
const posts = yield call(fetchGetPosts);
yield put(setPosts(posts));
} catch (err) {
yield put(setErrorPosts(err));
}
}
export default function* watchSaga() {
yield takeEvery(POSTS.LOADING, workerGetPosts);
}
actions.js
import { POSTS } from "../constants";
export const loadPosts = () => {
console.log('action-load')
return {
type: POSTS.LOADING
}
};
export const setPosts = payload => ({
type: POSTS.LOAD_SUCCESS,
payload
});
export const setErrorPosts = error => ({
type: POSTS.ERROR,
error
});
rootReducer.js
import { combineReducers } from "redux";
import postsReducer from "./reducer-posts";
import loadReducer from "./reducer-load";
const rootReducer = combineReducers({
posts: postsReducer,
isLoad: loadReducer
});
export default rootReducer;
reducer-posts.js
import { POSTS } from "../constants";
const postState = {
posts: []
};
function postsReducer(state = postState, action) {
switch (action.type) {
case POSTS.LOAD_SUCCESS:
return {
...state,
posts: [...action.payload]
};
default:
return state;
}
}
export default postsReducer;
reducer-load.js
import { POSTS } from "../constants";
import { combineReducers } from "redux";
const loadReducerPosts = (state = false, action) => {
switch (action.type) {
case POSTS.LOADING: return false;
case POSTS.LOAD_SUCCESS: return true;
case POSTS.ERROR: return false;
default: return state;
}
};
const loadReducer = combineReducers({
isLoadPost: loadReducerPosts,
});
export default loadReducer;
news.jsx
class News extends Component {
componentDidMount() {
loadPosts();
}
render() {
CONST { loadPosts }this.props
return (
<main>
// code
<button onClick={loadPosts}>Test Button</button>
</main>
);
}
}
const mapStateToProps = (
{ posts: { loading, posts, success } }
) => ({
posts,
loading,
success
});
export default connect(
mapStateToProps,
{ loadPosts }
)(News);

loadPosts method is available as props to the React component in current case. Unlike in componentDidMount, on button click you are calling the function from props. You have to use this.props.loadPosts() on both places

Redux-thunk dispatch function doesn't work on Laravel

I'm using React-Laravel for my project.
The problem is when I tried to use redux-thunk for the asynchronous dispatch function.
My dispatch function won't get executed.
Please do help me figure out this problem.
I have already tried to use promise or redux-devtools-extension library
https://codeburst.io/reactjs-app-with-laravel-restful-api-endpoint-part-2-aef12fe6db02
app.js
import React from 'react';
import ReactDOM from 'react-dom';
import { BrowserRouter } from 'react-router-dom';
import { createStore, combineReducers, applyMiddleware, compose } from 'redux';
import { Provider } from 'react-redux';
import thunk from 'redux-thunk';
import logger from 'redux-logger';
import Layout from './jsx/Layout/Layout';
import marketplaceReducer from './store/reducers/marketplace';
const composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;
const appReducer = combineReducers({
marketplace: marketplaceReducer
});
const rootReducer = (state, action) => {
return appReducer(state, action);
}
const store = createStore(rootReducer, composeEnhancers(
applyMiddleware(logger, thunk)
));
const render = (
<Provider store={store}>
<BrowserRouter>
<Layout />
</BrowserRouter>
</Provider>
);
ReactDOM.render(render, document.getElementById('root'));
marketplace.js (action)
import * as actionTypes from './actionTypes';
import axios from '../../axios';
export const loadMarketplace = () => {
console.log("Load Marketplace");
return {
type: actionTypes.LOAD_MARKETPLACE
};
}
export const successMarketplace = (data) => {
console.log("Success Marketplace");
return {
type: actionTypes.SUCCESS_MARKETPLACE,
data: data
}
}
export const failedMarketplace = () => {
console.log("Failed Marketplace");
return {
type: actionTypes.FAILED_MARKETPLACE
}
}
export const showMarketplace = () => {
console.log("Show Marketplace Action")
return dispatch => {
//This is the problem
//Inside this function, I can't see any console.log, even loadMarketplace() didn't get called.
console.log("Show Marketplace in dispatch");
dispatch(loadMarketplace());
axios.get('/marketplaces')
.then(response => {
dispatch(successMarketplace(response));
})
.catch(error => {
dispatch(failedMarketplace());
});
};
}
marketplace.js (reducer)
import * as actionTypes from '../actions/actionTypes';
const initial_state = {
data: [],
loading: false
}
const loadMarketplace = (state, action) => {
console.log("Load Marketplace Reducer")
return {
...state,
loading: true
};
}
const successMarketplace = (state, action) => {
console.log("Success Marketplace Reducer", action.data)
return {
...state,
loading: false,
data: action.data
};
}
const failedMarketplace = (state, action) => {
return {
...state,
loading: false
};
}
const reducer = (state = initial_state, action) => {
//This is called when the first init, never got it through showMarketplace() function.
console.log("Marketplace Reducer", action);
switch (action.type) {
case actionTypes.LOAD_MARKETPLACE: return loadMarketplace(state, action);
case actionTypes.SUCCESS_MARKETPLACE: return successMarketplace(state, action);
case actionTypes.FAILED_MARKETPLACE: return failedMarketplace(state, action);
default: return state;
}
}
export default reducer;
Marketplace.js (jsx view)
import React, { Component } from 'react';
import { connect } from 'react-redux';
import * as actions from '../../../store/actions';
class Marketplace extends Component {
componentDidMount() {
console.log('[ComponentDidMount] Marketplace')
this.props.showMarketplace();
}
render() {
return (
<React.Fragment>
Marketplace
</React.Fragment>
);
}
}
const mapDispatchToProps = dispatch => {
return {
showMarketplace: () => dispatch(actions.showMarketplace)
};
}
export default connect(null, mapDispatchToProps)(Marketplace);
This is the result of my console.log (when loading the first time for Marketplace.js)
Please do help, I've been struggling for 2 hours or more, only because of this problem. (This is my first time using React-Laravel).
Thank you.

I already found the problem. It is not redux-thunk problem.
It is actually a normal Redux problem we found anywhere.
Marketplace.js (jsx view)
import React, { Component } from 'react';
import { connect } from 'react-redux';
import * as actions from '../../../store/actions';
class Marketplace extends Component {
componentDidMount() {
console.log('[ComponentDidMount] Marketplace')
this.props.showMarketplace();
}
render() {
return (
<React.Fragment>
Marketplace
</React.Fragment>
);
}
}
const mapDispatchToProps = dispatch => {
return {
showMarketplace: () => dispatch(actions.showMarketplace) //THIS IS THE PROBLEM, IT IS NOT EXECUTING PROPERLY. THIS ONE SHOULD BE
showMarketplace: () => dispatch(actions.showMarketplace()) //SHOULD BE LIKE THIS.
};
}
export default connect(null, mapDispatchToProps)(Marketplace);

Edited: I think it is something about thunk is not added right to redux.
First of all try to add only thunk.
const store = createStore(rootReducer, composeEnhancers(
applyMiddleware(thunk)
));
If it works, maybe try to change the order of them.

How to get access to a specific reducer variables as props from react without using routes

I'm developing a react-redux app and I can get access to the reducers via routes. Now I'm facing the trouble of getting access to a specific reducer without using routes.
Here is my reducers.js:
const initialState = {
loading: false,
topics: []
};
export default createReducer(initialState, {
[LOADING_DATA]: (state, action) => {
return Object.assign({}, state, {
loading: action.loading
});
}
});
This is my actions.js:
export function loading (loading) {
return {
type: LOADING_DATA,
payload: {loading}
};
}
And this is what I have on my component:
import {connect} from 'react-redux'
import {bindActionCreators} from 'redux';
import * as moduleActionCreators from '...';
import * as actionCreators from '...';
class MyComponent extends Component {
...
render () {
return (<div>
...
</div>;
}
}
const mapStateToProps = (state) => ({
});
const mapDispatchToProps = (dispatch) => ({
actions: bindActionCreators(Object.assign({}, moduleActionCreators, actionCreators), dispatch)
});
export default connect(mapStateToProps, mapDispatchToProps)(MyComponent);
Normally in the mapStateToProps I reference the reducer variables as loading: state['my_reference_to_reducer'].loading but I can't figure it out how to tell the component to reference my reducers.js in order to get loading as props.
I would appreciate a light on this.

You need to set up the state in mapStateToProps function in order to access it:
const mapStateToProps = (state) => {
return {
loading: state.loading
}
}
Then you should be able to use it as this.props.loading in MyComponent.
Your reducer can look like this:
export default function reducer(state = {}, action) {
switch(action.type) {
case 'LOADING_DATA':
return Object.assign({}, state, {
...state,
loading: action.payload.loading
})
I recommend you to use redux ducks pattern as it keeps action creators and reducers at the same file, saves you time and makes it easier to read and use. For example:
loading.js
// Actions
const LOADING_DATA = 'LOADING_DATA'
// Action Creators
export const loadingData = (data) => {
return {
type: LOADING_DATA,
payload: {
loading: data
}
}
}
// Reducer
export default function reducer(state = {
loading: 'DATA zeroed'
}, action) {
switch(action.type) {
case 'LOADING_DATA':
return Object.assign({}, state, {
...state,
loading: action.payload.loading
})
default:
return state
}
}
index.js
import React from 'react';
import ReactDOM from 'react-dom';
import MyComponent from './MyComponent';
import configureStore from './configureStore'
const store = configureStore()
ReactDOM.render(
<MyComponent store={store}/>,
document.getElementById('root')
);
configureStore.js
import { createStore } from 'redux'
import { composeWithDevTools } from 'redux-devtools-extension'
import loadingData from './loading'
const configureStore = () => {
return createStore(loadingData, composeWithDevTools())
}
export default configureStore
MyComponent.js
import React, { Component } from 'react';
import { connect } from 'react-redux';
import { loadingData } from './loading';
class MyComponent extends Component {
constructor(props){
super(props)
this.onLoadingData = this.onLoadingData.bind(this)
}
componentDidMount() {
this.props.loadingData('no more undefined')
}
onLoadingData() {
this.props.loadingData('DATA')
}
render() {
console.log(this.props.loading)
return (
<div>
<h2>MyComponent</h2>
<button onClick={this.onLoadingData}>Load Data</button>
<p>{this.props.loading}</p>
</div>
);
}
}
const mapStateToProps = (state) => {
return {
loading: state.loading
}
}
const mapDispatchToProps = {
loadingData
}
export default connect(
mapStateToProps,
mapDispatchToProps
)(MyComponent)