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

Setting a component state

In this section, you're going to write some React code that sets the state of components. First, you'll learn about the initial state—that is, the default state of a component. Next, you'll learn how to change the state of a component, causing it to re-render itself. Finally, you'll see how a new state is merged with an existing state.

Setting an initial component state

The initial state of a component isn't actually required, but if your component uses state, it should be set. This is because if the component expects certain state properties to be there and they aren't, then the component will either fail or render something unexpected. Thankfully, it's easy to set the initial component state.

The initial state of a component should always be an object with one or more properties. For example, you might have a component that uses a single array as its state. This is fine, but just make sure that you set the initial array...