title: I want to use scrollTo
body: <p>I work on a project in React Native and I would like to set my <code>ScrollView</code> position. So I search and I found we should do this with <code>scrollTo</code> but I have an error:</p>
  
  <blockquote>
  <pre><code>TypeError: Cannot read property 'scrollTo' of undefined
  </code></pre>
  </blockquote>
  
  <p>My code:</p>
  
  <pre><code>export default class Index_calendar extends Component {
   componentDidMount() {
     const _scrollView = this.scrollView;
     _scrollView.scrollTo({x: 100});
   }
  
   render() {
     return (
       &lt;ScrollView ref={scrollView =&gt; this.scrollView = scrollView}&gt;
         {this.renderCalandar()}
       &lt;/ScrollView&gt;
     );
   }
  }
  </code></pre>