Welcome to our tutorial on Day 79 of learning React. Today, we will be focusing on the useCallback() hook in React JS, which is a very useful hook for optimizing performance in your React applications. This hook is especially handy when dealing with components that rely on functions as props, as it helps in preventing unnecessary re-renders.
To begin, let’s start by creating a new React project. If you haven’t already set up your development environment for React, you can refer to our previous tutorials for detailed instructions.
Once you have your project set up, open your code editor and create a new component where we will be using the useCallback() hook. Let’s call this component "ExampleComponent".
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>React useCallback() Hook</title>
</head>
<body>
<div id="root"></div>
</body>
</html>Now, let’s create the ExampleComponent in a separate file called ExampleComponent.js:
import React, { useCallback } from 'react';
const ExampleComponent = () => {
// Define a simple function that we will pass as a prop
const handleClick = () => {
console.log('Button clicked!');
};
// Use the useCallback() hook to memoize the function
const memoizedHandleClick = useCallback(handleClick, []);
return (
<div>
<button onClick={memoizedHandleClick}>Click me</button>
</div>
);
};
export default ExampleComponent;In this ExampleComponent, we have a simple button that, when clicked, will log a message to the console. We are using the useCallback() hook to memoize the handleClick function, ensuring that it will only be redefined if the dependency array (i.e., []) changes.
To use the ExampleComponent in your main App component, import it and render it as follows:
import React from 'react';
import ExampleComponent from './ExampleComponent';
const App = () => {
return (
<div>
<h1>React useCallback() Hook Tutorial</h1>
<ExampleComponent />
</div>
);
};
export default App;That’s it! You have now successfully used the useCallback() hook in your React application to optimize the performance of your components. Make sure to experiment with different scenarios and dependencies to see how useCallback() can help you in improving your React application’s performance.
We hope this tutorial was helpful for beginners in React. Stay tuned for more tutorials on various React hooks and concepts. Happy coding!
