Building a React-Redux Counter: Understanding State Management with Redux in React
Tags: redux, react, javascript, webdev
Published: 2023-12-19 11:04:38


![Redux Counter](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/qcr3luhk57v1g42031bs.png)

In this post we will take a look at using Redux for managing the state in React apps. For that we'll make a simple redux counter project. Let's break down each part of the Redux implementation step by step:
 
Source Code : [Github](https://github.com/Remonhasan/react-redux-counter)

## Redux Basics 
Redux is a predictable state container for JavaScript apps. It helps manage the state of your application in a predictable way, making it easier to debug and understand how data changes over time.

## Setting Up the Folder Structure
# Actions
Actions are payloads of information that send data from your application to your Redux store. In the `actions` folder:

- `actionTypes.js`: Defines action types as constants.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/3fvs13iczf4a9rrnr8gb.png)

- `counterActions.js`: Contains action creator functions that return actions.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/afztjvp25mqt3z970udn.png)

# Reducers
Reducers specify how the application's state changes in response to actions sent to the store. In the `reducers` folder:

- `counterReducer.js`: Defines how the state for the counter should change based on dispatched actions.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/v9a4paj4yrr83w6y7y2o.png)

- `index.js`: Combines all reducers using `combineReducers` from Redux.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/eygyv4bovjy01ht541ft.png)

# Store
The store holds the state of the application. In the `store` folder: `index.js`: Creates the Redux store using the combined reducers.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/0e3yfhb9fl0u0xmtvb93.png)

## Setting Up Redux in App
`App.js` : Wraps the entire app with the Redux `Provider`, which makes the Redux store available to any nested components.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/grxtgsx5xm9nyur4hbld.png)

## Configuring Redux in the App
# `components/Counter.js` 

- This is a functional component connected to Redux using the connect function from `react-redux`.

- `mapStateToProps` is a function that maps parts of the Redux state to the component's props.

- `mapDispatchToProps` is an object that maps action creators to props.

- `connect` connects the component to the Redux store, allowing it to access the state and dispatch actions.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/1spe4quiw0fei8a3tb42.png)

## Running the App
# Starting the Application
Run `npm start` to start the React application.

## Summary

1. **Actions** are dispatched to describe something that happened (like "INCREMENT" or "DECREMENT").
2. **Reducers** describe how the application's state changes in response to actions.
3. **Store** holds the application's state.
4. **Connecting Components** allows them to access the Redux store's state and dispatch actions.

This breakdown covers the foundational parts of a simple Redux setup in a React application. Understanding these sections will help you grasp how Redux manages state and data flow in a React application. If any specific part needs further explanation, feel free to ask!