Investigate and replace the document.click event logic about react-dropdownbox

[jennianelson]

This was easy, and it worked: https://medium.com/@pitipatdop/little-neat-trick-to-capture-click-outside-react-component-5604830beb7f

One of the comments suggested exposing the child ref to the parent like this, but did not give any reason why one approach is preferred over another.

class Parent extends React.Component {
  constructor(props){
    super(props);
    this.childRef = React.createRef();
  }
  render() {
    <Child domRef={this.childRef} />
  }
}
class Child extends React.Component {
  render() {
    return <div ref={this.props.domRef}>Parent knows about me</div>
  }
}