title: React Native - Call Function of child from NavigatorIOS
body: <p>I am trying to call a child function from the right button on the parent navigator.</p>
  
  <p>A basic code example of what I need is as follows:</p>
  
  <p>Main.js</p>
  
  <pre><code>&lt;NavigatorIOS
      style={styles.container}
      initialRoute={{
          title: 'Test',
          component: Test,
          rightButtonTitle: 'Change String',
          onRightButtonPress: () =&gt; ***I Want to call miscFunction from here*** ,
          passProps: {
              FBId: this.state.fbidProp,
              favsPage: true
          }
      }}/&gt;
  </code></pre>
  
  <p>Test.js</p>
  
  <pre><code>class Test extends React.Component{
      constructor(props){
          super(props);
          this.state = {
              variable: 'some string'
          };
      }
      miscFunction(){
          this.setState({
              variable: 'new string'
          };
      }
      render(){
          return(
              &lt;Text&gt; {variable} &lt;/Text&gt;
          )
      }
  }
  </code></pre>