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)

useMemo examples

The useMemo hook tends to be a hook that we use when we want to optimize the site for either resolving site performance and/or improving user experience. Thus, it normally tends to be used to address problems. In the following sections, we will go through two examples relating to a search to demonstrate the application of useMemo as an optimization tool.

Clicking to search

Say you have a list of fruits and you'd like to search it to find the matched fruit using an input box and a button. For example, typing "bl" should return us blackberries and blueberries from a list of fruits.

Figure 6.3 – Clicking on the search UI

Here's a list of fruits defined in a fruits global variable:

const fruits = ["Apple", "Banana", "Blackberries", ...]

We use a text state to store the string that the user types in at the moment. When the user clicks the Search button, the current text is sent...