Example of React component in Typescript using a callback to set a ref

callbackRef.tsx

import * as React from "react";

class CallbackRef extends React.Component {
    divRef: HTMLDivElement | null = null;

    setDivRef = (element: HTMLDivElement) => {
        this.divRef = element;
    };

    componentDidMount() {
        if (this.divRef) {
            console.log(`callbackRef div width: ${this.divRef.clientWidth}`);
        }
    }

    render() {
        return <div ref={this.setDivRef} style={{ width: "100%", height: "30px", backgroundColor: "red" }} />;
    }
}

export default CallbackRef;