Resource Hooks in React

In React, components often need to access external resources such as data from promises or context information for styling. Managing these resources within the component state could lead to unnecessary complexity and performance overhead. React provides a simple solution with the 'use' hook to overcome this. This hook allows components to easily access and consume resources without the need to incorporate them into the component state.

In this article, we'll explore the power of the 'use' hook and how it can help resource access within React components.

Understanding the 'use' Hook:

The 'use' hook is a versatile tool introduced in React, that helps components to consume various resources efficiently. use is a React Hook that lets you read the value of a resource like a Promise or context. They are used for reading data from a promise, accessing context information, or interacting with other asynchronous operations. Unlike all other React Hooks, use can be called within loops and conditional statements like if. Like other React Hooks, the function that calls use must be a Component or Hook.

Syntax:

const value = use(resource);

Parameters 

• resource: this is the source of the data you want to read a value from. A resource can be a Promise or a context.

Return Type:

The use Hook returns the value that was read from the resource like the resolved value of a Promise or context.

Benefits of Using the 'use' Hook:

1. Simplified Resource Consumption: The 'use' hook simplifies the process of accessing external data sources, promises, or context information within components.
2. Improved Performance: Since components can access resources directly without the need for additional state management, the 'use' hook can lead to improved performance and reduced overhead.
3. Enhanced Modularity: Components become more modular and reusable by decoupling resource consumption from state management. This modular approach helps better code organization and provides easier maintenance.
4. Consistent API: The 'use' hook provides a consistent API for consuming various types of resources, which makes it easier to understand and work with different components across the codebase.

Example: In this example 'use' is used to read resources of ThemeContext.

import { createContext, use } from 'react';

const ThemeContext = createContext(null);

export default function MyApp() {
    return (
        <ThemeContext.Provider value="dark">
            <Form />
        </ThemeContext.Provider>
    )
}

function Form() {
    return (
        <Panel title="Welcome">
            <Button show={true}>Sign up</Button>
            <Button show={false}>Log in</Button>
        </Panel>
    );
}

function Panel({ title, children }) {
    const theme = use(ThemeContext);
    const className = 'panel-' + theme;
    return (
        <section className={className}>
            <h1>{title}</h1>
            {children}
        </section>
    )
}

function Button({ show, children }) {
    if (show) {
        const theme = use(ThemeContext);
        const className = 'button-' + theme;
        return (
            <button className={className}>
                {children}
            </button>
        );
    }
    return false
}

Output: