title: Ref to child component
body: <p>I am unable to access a child's function using ref.
  If I try to examine <code>this.child.current</code> the <code>props</code> of the child is listed.</p>
  
  <pre class="lang-js prettyprint-override"><code>class BottomPanel extends React.Component&lt;Props, {}&gt; {
    constructor(props) {
      super(props);
      this.child = React.createRef();
      this.onClick = this.onClick.bind(this);
    }
  
    onClick() {
      this.child.current.getAlert();
    }
  
    render() {
      &lt;div&gt;
        &lt;BottomPanelPeriodList ref={this.child}&gt;
          &lt;div label={&lt;FormattedMessage id="bottomPanel.threeMonth" /&gt;} /&gt;
          &lt;div label={&lt;FormattedMessage id="bottomPanel.sixMonth" /&gt;} /&gt;
        &lt;/BottomPanelPeriodList&gt;
      &lt;/div&gt;
    }
  }
  export default connect(mapStateToProps)(BottomPanel);
  
  class BottomPanelPeriodList extends React.Component&lt;Props, State&gt; {
    getAlert = () =&gt; {
      alert('HELLOWORLD!');
    };
  
    render() {
      ...
    }
  }
  export default connect(null, mapDispatchToProps, null, { forwardRef: true })(BottomPanelPeriodList);
  </code></pre>