antd-mobile/es/components/popover/wrapper.js

<img src="https://gw.alipayobjects.com/mdn/rms_ee68a8/afts/img/A*hjjDS5Yy-ooAAAAAAAAAAAAAARQnAQ" alt="logo" width="100%" />

import React from 'react';
import { findDOMNode } from 'react-dom';
export class Wrapper extends React.Component {
  constructor() {
    super(...arguments);
    this.element = null;
  }

  componentDidMount() {
    this.componentDidUpdate();
  }

  componentDidUpdate() {
    // eslint-disable-next-line
    const node = findDOMNode(this);

    if (node instanceof Element) {
      this.element = node;
    } else {
      this.element = null;
    }
  }

  render() {
    return React.Children.only(this.props.children);
  }

}