forked from facebook/docusaurus
/
useMutationObserver.ts
38 lines (34 loc) · 1 KB
/
useMutationObserver.ts
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/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
import {useRef, useMemo, useEffect} from 'react';
import ExecutionEnvironment from '@docusaurus/ExecutionEnvironment';
export function useMutationObserver(
target: Element | undefined | null,
callback: (mutations: MutationRecord[]) => void,
options = {
attributes: true,
characterData: true,
childList: true,
subtree: true,
},
): void {
const mutationObserver = useRef<MutationObserver | undefined>(
ExecutionEnvironment.canUseDOM ? new MutationObserver(callback) : undefined,
);
const memoOptions = useMemo(() => options, [options]);
useEffect(() => {
const observer = mutationObserver.current;
if (target && observer) {
observer.observe(target, memoOptions);
}
return () => {
if (observer) {
observer.disconnect();
}
};
}, [target, memoOptions]);
}