React Native NavigatorIOS - how to use onRightButtonPress to call a component method

react-native-navigator-ios-right-button.jsx

const MyComponent = React.createClass({
    statics: {
        getRoute: function (props:Object) {
            // To pass in the onLeft/RightButton press
            // to out instance we need to use the 'ref'
            // function (in passProps).
            // This'll be passed the component instance, that we can call the methods on.. Phew!
            let instance = null;

            const route = {
                component: MyComponent,
                title: "My Title",
                rightButtonIcon: require("../../images/lightbulb.png"),
                onRightButtonPress: () => {
                    if (instance && instance._onRightPressed) {
                        instance._onRightPressed();
                    }
                },
                backButtonTitle: "Back",
                passProps: Object.assign({}, {ref: (item)=>instance = item}, props),
            };
            return route;
        }
    },
    .....