Redux Tutorial in React JS

What is Redux? 

Redux is the library that is used to distribute the project on different project layers, we can easily manage large & complex projects using this library. Redux library is also useful to debug the application easily can provide better structure and code using Redux.

It contains a separate layer for View, Action, Reducers, and Store.

The store reflected is the brain or main part of redux when we perform any action then the first reducers will map this action and implement operation and that operation will be reflect under store, the store will update the view according to action.it brings the actions and reducers together, holding and changing the state for the whole app.

Action is called an event if we want to perform any operation in view then action will handle that event and pass it to reducers.it contains two properties, one describing the type of action, and another describing what should be changed in the app state.

Reducers are the intermediary between Actions and Store. these are functions that implement the functionality of the actions. it changes the state of the app, based on the action description and the state change description.

Example of Redux.

Now i am explaining the example to control the  welcome logo of react under toggle click.

Create React Project

npx create-react-app scs-redux-tutorial

cd scs-redux-tutorial

Install Redux

 npm install --save redux react-redux

Create actions folder under src and create two file startAction.js and stopAction.js

export const startAction = {

    type: "rotate",

    payload: true

  };

export const stopAction = {

    type: "rotate",

    payload: false

  };

Create reducers folder under src and create rotateReducer.js

export default (state, action) => {

    switch (action.type) {

      case "rotate":

        return {

          rotating: action.payload

        };

      default:

        return state;

    }

  };

create store.js file under src without folder

import { createStore } from "redux";

import rotateReducer from "./reducers/rotateReducer";

function configureStore(state = { rotating: false }) {

  return createStore(rotateReducer,state);

}

export default configureStore;

Go into app.css and replace all css into these css

.App {

  text-align: center;

}

.App-logo {

  animation: App-logo-spin infinite 20s linear;

  height: 40vmin;

}

/* new class here */

.App-logo-paused {

  animation-play-state: paused;

}

.App-header {

  background-color: #282c34;

  min-height: 100vh;

  display: flex;

  flex-direction: column;

  align-items: center;

  justify-content: center;

  font-size: calc(10px + 2vmin);

  color: white;

}

.App-link {

  color: #61dafb;

}

@keyframes App-logo-spin {

  from {

    transform: rotate(0deg);

  }

  to {

    transform: rotate(360deg);

  }

}

go into app.js and write following code

import logo from './logo.svg';

import './App.css';

import { connect } from "react-redux";

import { startAction } from "./actions/startAction";

import { stopAction } from "./actions/stopAction";

import React from 'react';

class App extends React.Component{

  constructor(props)

  {

    super(props)

    this.fun = this.fun.bind(this);

  }

  fun()

  {

    alert("hello");

   

    //this.props.rotating?this.props.stopAction : this.props.startAction

  }

  render()

  {

    console.log(this.props.rotating)

  return (

    <div className="App">

      <header className="App-header">

      <img  src={logo} className={"App-logo" + (this.props.rotating ? "":" App-logo-paused")} alt="logo" onClick={this.props.rotating?this.props.stopAction : this.props.startAction}  />

        <p>

        <input type="button" onClick={this.props.rotating?this.props.stopAction : this.props.startAction} value="click"/>

        </p>

       

      </header>

    </div>

  );

  }

}

const mapStateToProps = state => ({

  ...state

});

const mapDispatchToProps = dispatch => ({

  startAction: () => dispatch(startAction),

  stopAction: () => dispatch(stopAction)

});

export default connect(mapStateToProps, mapDispatchToProps)(App);

go into index.js file and write following code

import React from 'react';

import ReactDOM from 'react-dom/client';

import './index.css';

import { Provider } from "react-redux";

import configureStore from "./store";

import App from './App';

import reportWebVitals from './reportWebVitals';

const root = ReactDOM.createRoot(document.getElementById('root'));

root.render(

  <React.StrictMode>

    <Provider store={configureStore()}>

    <App />

  </Provider>

  </React.StrictMode>

);

// If you want to start measuring performance in your app, pass a function

// to log results (for example: reportWebVitals(console.log))

// or send to an analytics endpoint. Learn more: https://bit.ly/CRA-vitals

reportWebVitals();