Book Image

The React Workshop

By : Brandon Richey, Ryan Yu, Endre Vegh, Theofanis Despoudis, Anton Punith, Florian Sloot
5 (1)
Book Image

The React Workshop

5 (1)
By: Brandon Richey, Ryan Yu, Endre Vegh, Theofanis Despoudis, Anton Punith, Florian Sloot

Overview of this book

Are you interested in how React takes command of the view layer for web and mobile apps and changes the data of large web applications without needing to reload the page? This workshop will help you learn how and show you how to develop and enhance web apps using the features of the React framework with interesting examples and exercises. The workshop starts by demonstrating how to create your first React project. You’ll tap into React’s popular feature JSX to develop templates and use DOM events to make your project interactive. Next, you’ll focus on the lifecycle of the React component and understand how components are created, mounted, unmounted, and destroyed. Later, you’ll create and customize components to understand the data flow in React and how props and state communicate between components. You’ll also use Formik to create forms in React to explore the concept of controlled and uncontrolled components and even play with React Router to navigate between React components. The chapters that follow will help you build an interesting image-search app to fetch data from the outside world and populate the data to the React app. Finally, you’ll understand what ref API is and how it is used to manipulate DOM in an imperative way. By the end of this React book, you’ll have the skills you need to set up and create web apps using React.
Table of Contents (20 chapters)
Preface

The Update Lifecycle

The update loop segment of the lifecycle is something that lives for the entire lifetime of the component (where the lifetime of a component is if it needs to be displayed in the DOM). This loop repeats every time that the component needs to be updated, which is basically whenever any data that affects what needs to be loaded and displayed as the DOM changes which will then start a lifecycle method specifically to determine what changes need to be displayed. For example, if you modify the shouldComponentUpdate() lifecycle function to just always return false, then as far as React is concerned, no changes should ever retrigger the update loop. Similarly, if you always return true, like we did in our first exercise, then React will assume every state or props change needs to retrigger re-rendering.

render()

We have already discussed the render function, but it is worth mentioning that this is when the render function gets called each time the component updates...