Book Image

Designing React Hooks the Right Way

By : Fang Jin
Book Image

Designing React Hooks the Right Way

By: Fang Jin

Overview of this book

React hook creates a unique solution for using states in function components to orchestrate UI communication. They provide you with an easy interface to write custom data management solutions with low development and maintenance costs. Understanding how Hooks are designed enables you to use them more effectively, and this book helps you to do just that. This book starts with a custom-crafted solution to reveal why Hooks are needed in the first place. You will learn about the React engine and discover how each built-in Hook can manage a persistent value by hooking into it. You will walk through the design and implementation of each hook with code so that you gain a solid understanding. Finally, you'll get to grips with each Hook's pitfalls and find out how to effectively overcome them. By the end of this React book, you'll have gained the confidence to build and write Hooks for developing functional and efficient web applications at scale.
Table of Contents (12 chapters)

State in React

By now, you should have some idea of what a state is. To recap, a state is a piece of memory stored inside a fiber, introduced in Chapter 3, Hooking into React. When combined with props, a state can represent a UI screen deterministically.

Figure 4.1 – A fiber tree with a source fiber

For example, let's say we build a site and end up with a fiber tree (such as the one seen in Figure 4.1). When a user makes an action (such as a click), the action sends a signal via an event handler to a fiber (the red dot in Figure 4.1). We call this fiber a source fiber.

Now, say the dispatched event changes a counter from 0 to 1. React should schedule an update based on this user action and then prepare all of the Document Object Model (DOM) elements for the screen. Assuming the red lines are the fibers that need to be changed, how does React figure this out?

Upon receiving this update request, React goes through the fiber tree from the root...