title: How to get the DOM node of a child
body: <p>I want to access the DOM node of a child component defined in a parent component. In the sample below I've tried both the "try1" and "try2" methods and neither works. How do I get the DOM node for the "theDiv" ref?</p>
  
  <pre><code>&lt;Form&gt;
      &lt;Frame&gt;
          &lt;div ref="thediv" /&gt;
      &lt;/Frame&gt;
  &lt;/Form&gt;
  
  Form.render() {
      return (
         &lt;Frame&gt;
             &lt;div ref="theDiv" /&gt;
         &lt;/Frame&gt;
  }
  
  try1.Frame.componentDidMount() {
      let theDiv = ReactDOM.findDOMNode(this.refs.theDiv);
  }
  
  try2.Frame.componentDidMount() {
      React.Children.forEach(this.props.children, child =&gt; {
         if (child.ref === "theDiv") {
             let theDiv = ReactDOM.findDOMNode(child);
         }
      });
  }
  </code></pre>