import React from 'react'; import * as PropTypes from 'prop-types'; // Header component to be used as default for all the columns. export default class HeaderGroupComponent extends React.Component { constructor(props) { super(props); this.props.columnGroup.getOriginalColumnGroup().addEventListener('expandedChanged', this.onExpandChanged.bind(this)); this.state = { expanded: null }; } componentDidMount() { this.onExpandChanged(); } render() { let arrowClassName = "customExpandButton " + (this.state.expanded ? " expanded" : " collapsed"); return