useLexicalNode.js

hook useLexicalNode<TReturn, TNode: LexicalNode>(
  nodeKey: NodeKey,
  callback: (TNode | null) => TReturn,
  predicate: (node: LexicalNode | null) => node is TNode,
): TReturn {
  return useLexicalSubscription<TReturn>((editor: LexicalEditor) => {
    const getValue = () => {
      return editor.read(() => {
        const node = $getNodeByKey<LexicalNode>(nodeKey);
        return callback(predicate(node) ? node : null);
      });
    };

    return {
      initialValueFn() {
        return getValue();
      },
      subscribe(setValue) {
        return editor.registerUpdateListener(() => {
          setValue(getValue());
        });
      },
    };
  });
}