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

Uncontrolled Components

We will start with a brief understanding of how forms are handled in React. In the most basic case, React treats forms as normal HTML components. Sometimes, we might need to take a close look at that input in a form so that we can see what its current value is. The most convenient way to achieve that is by using uncontrolled components, where, in essence, we maintain separate references to the DOM elements that we can utilize to manipulate and read the elements. By uncontrolled, we mean that we do not use React to change the value of the input field, but we let the browser handle the changes when we type something. This means that we can still write forms as usual and they would work as expected, as they do with plain HTML.

Uncontrolled components are useful when developers want to deal with the final state rather than the intermediate state of the component. For example, we can have the following form that asks for a username and a password:

import React...