streamlit-component-lib-react-hooks/dist/esm/useNullableRenderData.js

An npm package that provides support code for creating [Streamlit Components](https://docs.streamlit.io/en/stable/streamlit_components.html) with React and React Hooks.

import { useState, useEffect } from "react";
import { Streamlit } from "streamlit-component-lib";
/**
 * Returns `RenderData` received from Streamlit after the first render event received.
 */
export const useNullableRenderData = () => {
    const [renderData, setRenderData] = useState();
    useEffect(() => {
        const onRenderEvent = (event) => {
            const renderEvent = event;
            setRenderData(renderEvent.detail);
        };
        // Set up event listeners, and signal to Streamlit that we're ready.
        // We won't render the component until we receive the first RENDER_EVENT.
        Streamlit.events.addEventListener(Streamlit.RENDER_EVENT, onRenderEvent);
        Streamlit.setComponentReady();
        const cleanup = () => {
            Streamlit.events.removeEventListener(Streamlit.RENDER_EVENT, onRenderEvent);
        };
        return cleanup;
    }, []);
    return renderData;
};