Book Image

React and React Native - Third Edition

By : Adam Boduch, Roy Derks
Book Image

React and React Native - Third Edition

By: Adam Boduch, Roy Derks

Overview of this book

React and React Native, Facebook’s innovative User Interface (UI) libraries, are designed to help you build robust cross-platform web and mobile applications. This updated third edition is improved and updated to cover the latest version of React. The book particularly focuses on the latest developments in the React ecosystem, such as modern Hook implementations, code splitting using lazy components and Suspense, user interface framework components using Material-UI, and Apollo. In terms of React Native, the book has been updated to version 0.62 and demonstrates how to apply native UI components for your existing mobile apps using NativeBase. You will begin by learning about the essential building blocks of React components. Next, you’ll progress to working with higher-level functionalities in application development, before putting this knowledge to use by developing user interface components for the web and for native platforms. In the concluding chapters, you’ll learn how to bring your application together with a robust data architecture. By the end of this book, you’ll be able to build React applications for the web and React Native applications for multiple mobile platforms.
Table of Contents (33 chapters)
Section 1: React
Section 2: React Native
Section 3: React Architecture

Optimizing rendering efficiency

The next life cycle method you're going to learn about is used to implement heuristics that improve component rendering performance. You'll see that if the state of a component hasn't changed, then there's no need to render. Then, you'll implement a component that uses specific metadata from the API to determine whether or not the component needs to be re-rendered.

To render or not to render

The shouldComponentUpdate() life cycle method is used to determine whether or not the component will render when asked to. For example, if this method were implemented and returned false, the entire life cycle of the component would short-circuit, and no render would happen. This can be an important check to have in place if the component is rendering a lot of data and is re-rendered frequently. The trick is knowing whether or not the component state has changed.

Let's take a look at a simple list component:

import React, { Component }...