Redux in React Native

What is Redux in React Native?

Redux is a state management library that can be used in React Native (and also in React web applications). It provides a centralized store where you can store and manage the state of your application, making it easier to maintain and update.

With Redux, you can define actions that represent changes to the state. These actions are dispatched to the store, where a reducer function handles the action and returns the new state of the application.

For example, if you have a shopping cart application, you might define an action called ADD_TO_CART that takes in an item and adds it to the cart. When the user clicks the add to cart button, you would dispatch this action to the store, and the reducer function would update the state of the application to reflect the new item in the cart.

Using Redux in React Native can help simplify your application's state management and make it easier to reason about and maintain over time.

Prerequisites

To use Redux in React Native app, you need to install the redux and react-redux libraries, define your store, create your actions and reducers, and connect your components to the store. Once you get the hang of it, Redux can make your app development more efficient and easier to manage.

• Initiate a new React Native app using this command:

• Navigate into your project folder using this:

• Install the necessary Redux dependencies by running this command:

• Then start your React native application like this:

Implementation of Redux in React Native

To implement Redux in React Native, there are a few steps that need to be taken. These steps include creating a reducer, setting up a store, and creating and dispatching actions.

How to Create the Reducer

A reducer function plays a crucial role in a Redux application as it takes the current state of the application and an action object, and returns a new state that reflects the changes caused by that action. There are two common ways to create a reducer in a React Native application - using react-redux or redux toolkit.

In this code, the initialState object defines the initial state of the application before any actions have been dispatched. This object can be populated with any data you need to initialize your app's state.

The rootReducer function takes two arguments: state (which has a default value of initialState) and action. The switch statement inside the rootReducer allows you to define a function for each action type that updates the state accordingly. If the action type is not recognized, the reducer simply returns the existing state.

How to Create the Store and Provide to App

The Redux in React Native provides a centralized store where all the application state is stored. The createStore function is imported from the redux library and used to create a new store. The rootReducer function, which is imported from a separate reducers.js file, is passed as an argument to the createStore function.

With Redux in React Native, you can easily access and manipulate the state from any component in the application. This code creates a Redux store instance that is used to manage the state of a React Native app.

This code sets up the entry point of a React Native app and wraps the app with a Provider component that connects the app to the Redux store.

Create and Dispatch Actions

This code defines two action creators for a Redux store in a React Native app.

addToCart and removeFromCart are defined as functions that take an item argument. These functions create and return an action object with a type property equal to the appropriate action type constant (ADD_TO_CART or REMOVE_FROM_CART) and a payload property that contains the item object passed as an argument.

Here’s a code snippet that defines a component named Cart that renders a list of items and a shopping cart. It also uses Redux to manage the state of the cart.

Redux Toolkit

Redux Toolkit is a library that simplifies the use of Redux by providing a set of tools that automate common Redux patterns and reduce boilerplate code. It provides an alternative approach to creating a Redux store and reducer, making the process simpler and more efficient.

In simpler terms, think of Redux Toolkit as a tool that makes using Redux easier and faster by providing shortcuts and helpers that help you write less code. One of the key features of Redux in React Native is its ability to manage application states across different screens and components.

With Redux Toolkit, you can create a slice which is a bundle of Redux logic for a specific feature of your application. A slice includes the actions, reducers, and initial state needed to manage the state for that feature. This makes it easier to organize your code and keep things modular.

Redux Toolkit also includes a configureStore function that automatically sets up a Redux store with sane defaults, such as enabling the Redux DevTools extension and adding middleware for handling asynchronous actions.

In addition, Redux Toolkit includes a createAsyncThunk function that simplifies the handling of asynchronous actions, such as fetching data from a server. This function allows you to define a single action that handles both the pending and fulfilled states of an asynchronous action. By using Redux in React Native, you can easily handle asynchronous actions and side effects.

Create a React Redux App

This command creates a new React application with the Redux template using Create React App.

Redux Core

The Redux core library is available as a package on NPM for use with a module bundler or in a Node application:

Examples

This code sets up a Redux store using the Redux Toolkit.

The createSlice function is then used to create a slice of the store that handles the cart state. It takes an object with three properties:

• name: The name of the slice.
• initialState: The initial state of the slice.
• reducers: An object that contains functions that handle changes to the state.

The addToCart reducer adds an item to the cart array by pushing it onto the end of the array. The removeFromCart reducer removes an item from the cart array by filtering out the item that matches the action payload.

Here is an example of how to implement the same cart application using the Redux Toolkit.