--- title: React useOnGlobalEvent hook tags: hooks,effect,event author: chalarangelo cover: tropical-bike firstSeen: 2021-12-22T05:00:00-04:00 --- Executes a callback whenever an event occurs on the global object. - Use the `useRef()` hook to create a variable, `listener`, which will hold the listener reference. - Use the `useRef()` hook to create a variable that will hold the previous values of the `type` and `options` arguments. - Use the `useEffect()` hook and `EventTarget.addEventListener()` to listen to the given event `type` on the `Window` global object. - Use `EventTarget.removeEventListener()` to remove any existing listeners and clean up when the component unmounts. ```jsx const useOnGlobalEvent = (type, callback, options) => { const listener = React.useRef(null); const previousProps = React.useRef({ type, options }); React.useEffect(() => { const { type: previousType, options: previousOptions } = previousProps; if (listener.current) { window.removeEventListener( previousType, listener.current, previousOptions ); } listener.current = window.addEventListener(type, callback, options); previousProps.current = { type, options }; return () => { window.removeEventListener(type, listener.current, options); }; }, [callback, type, options]); }; ``` ```jsx const App = () => { useOnGlobalEvent('mousemove', e => { console.log(`(${e.x}, ${e.y})`); }); return
Move your mouse around
; }; ReactDOM.createRoot(document.getElementById('root')).render(