Book Image

Getting Started with React

By : Doel Sengupta, Manu Singhal, Danillo Corvalan
Book Image

Getting Started with React

By: Doel Sengupta, Manu Singhal, Danillo Corvalan

Overview of this book

ReactJS, popularly known as the V (view) of the MVC architecture, was developed by the Facebook and Instagram developers. It follows a unidirectional data flow, virtual DOM, and DOM difference that are generously leveraged in order to increase the performance of the UI. Getting Started with React will help you implement the Reactive paradigm to build stateless and asynchronous apps with React. We will begin with an overview of ReactJS and its evolution over the years, followed by building a simple React component. We will then build the same react component with JSX syntax to demystify its usage. You will see how to configure the Facebook Graph API, get your likes list, and render it using React. Following this, we will break the UI into components and you’ll learn how to establish communication between them and respond to users input/events in order to have the UI reflect their state. You’ll also get to grips with the ES6 syntaxes. Moving ahead, we will delve into the FLUX and its architecture, which is used to build client-side web applications and complements React’s composable view components by utilizing a unidirectional data flow. Towards the end, you’ll find out how to make your components reusable, and test and deploy them into a production environment. Finally, we’ll briefly touch on other topics such as React on the server side, Redux and some advanced concepts.
Table of Contents (18 chapters)
Getting Started with React
About the Authors
About the Reviewers

Chapter 5. Component Life cycle and Newer ECMAScript in React

So far, we have explored React component properties and how we need to initialize, update, and change the component's state(s) for interactive applications. Let's now explore the lifecycle of such a React component in this chapter. We will also dig into future ECMAScript syntax and a few changes that the React community also used from version 0.13.0. For this, we will review some ES6 and ES7 features within the React library.

While creating any React component by calling React.createClass(), we need to always have a render method. This render method returns a description of the DOM. React has a performance edge in our applications because React maintains a fast in-memory representation of the DOM and never directly interacts with the actual DOM. Thus, when the render method returns the description of the DOM, React can compare the difference between the actual DOM and the in-memory representation, and, based on the difference(s...