title: clear the material UI text field Value in react
body: <p>How to clear the materialUI textfield value in react?</p>
  
  <p>Check the below code - </p>
  
  <pre><code>&lt;TextField
    hintText=""
    ref={(node) =&gt; this._toField = node}
    onChange={this.changeToText}
    floatingLabelText="To*"
    floatingLabelFixed={true}
    fullWidth={true}
  /&gt;
  </code></pre>
  
  <p>I'm using the raisedButton while pressing it validate the above field. If the field has error then displaying the error message. If not, then we need to clear the input. But how can we clear the input text?</p>