title: (reactjs) get child component value
body: <p>i have the following react component Timepicker:</p>
  
  <pre><code>export default class TimePicker extends Component{
  
   render(){
     return(
       &lt;div&gt;
        &lt;input id={this.props.nameID} type="text"&gt;&lt;/input&gt;
        &lt;/div&gt;);
   }
  }  
  </code></pre>
  
  <p>TimePicker is used by SingleTask:</p>
  
  <pre><code>export default class SingleTask extends Component{
     ....
     render(){
       ....
       &lt;TimePicker nameID="time" /&gt;
      .....
    }
  }
  </code></pre>
  
  <p>How can I access the input value in TimePicker from SingleTask?</p>