JAVASCRIPT
useClickOutside Hook for Detecting Clicks Outside an Element
Create a `useClickOutside` React hook to detect clicks occurring outside a specified DOM element, perfect for closing dropdowns, modals, or tooltips.
import { useEffect, useRef, useState } from 'react';
const useClickOutside = (ref, handler) => {
useEffect(() => {
const listener = (event) => {
// Do nothing if clicking ref's element or descendant elements
if (!ref.current || ref.current.contains(event.target)) {
return;
}
handler(event);
};
document.addEventListener('mousedown', listener);
document.addEventListener('touchstart', listener);
return () => {
document.removeEventListener('mousedown', listener);
document.removeEventListener('touchstart', listener);
};
}, [ref, handler]); // Only re-run if ref or handler changes
};
// Example Usage:
// import React, { useRef, useState } from 'react';
// function Dropdown() {
// const [isOpen, setIsOpen] = useState(false);
// const dropdownRef = useRef(null);
//
// useClickOutside(dropdownRef, () => {
// if (isOpen) setIsOpen(false);
// });
//
// return (
// <div ref={dropdownRef} style={{ position: 'relative', display: 'inline-block' }}>
// <button onClick={() => setIsOpen(!isOpen)}>Toggle Dropdown</button>
// {isOpen && (
// <div style={{ position: 'absolute', top: '40px', left: '0', border: '1px solid black', padding: '10px', background: 'white' }}>
// Dropdown Content
// </div>
// )}
// </div>
// );
// }
How it works: The `useClickOutside` hook takes a `ref` to a DOM element and a `handler` function. It attaches `mousedown` and `touchstart` event listeners to the `document`. When a click or touch occurs, it checks if the event target is inside the `ref`'s current element. If the click is outside, the `handler` function is executed. This is ideal for dismissing UI elements like dropdowns, sidebars, or tooltips when a user clicks anywhere else on the page.