title: React-Native onPress doesn't work, when touch the icon
body: <p>I'am using <a href="https://github.com/react-native-training/react-native-elements" rel="nofollow noreferrer">react-native-element </a> to create a <a href="https://react-native-training.github.io/react-native-elements/docs/button_group.html" rel="nofollow noreferrer">button group</a>, that embedded an Icon from <a href="https://oblador.github.io/react-native-vector-icons/" rel="nofollow noreferrer">react-native-vector-icons </a>.</p>
  
  <p>the problem is that when the icon is touched, onPress does not get triggered </p>
  
  <pre><code>    constructor(props) {
        super(props);    
        this.state = { selectedIndex: 0 };   
        this.SetSelected = this.SetSelected.bind(this);
      }
  
  
      SetSelected(index) {
        this.setState({ selectedIndex: index });
      }
  
      return(
      &lt;ButtonGroup
        selectedIndex={this.state.selectedIndex}
        onPress={this.SetSelected}
        selectedButtonStyle={{ backgroundColor: 'blue' }}
        buttons={[
          {
            element: () =&gt; (
              &lt;Icon.Button
                name="slack"
                style={{ backgroundColor: 'white' }}
                color={'black'}
                size={30}
                title="Inbox"
              &gt;
                &lt;Text style={{ color: 'black', fontSize: 15, textAlignVertical: 'center', textAlign: 'center' }}                   
                &gt;
                  All
                &lt;/Text&gt;
              &lt;/Icon.Button&gt;
            ),
          })
  </code></pre>