SwapImageTest.js

import React, { Component } from 'react';

import {
  ViroScene,
  ViroImage,
  ViroButton,
} from 'react-viro';

let imageOne = {uri: "http://wiki.magicc.org/images/c/ce/MAGICC_logo_small.jpg"};
let imageTwo = {uri: "http://planetpixelemporium.com/images/fullsize/541moon.jpg"};

// [NEW] requiring/import the TestModuleVar module.
var TestModuleVar = require('./TestModuleVar');

var SwapImageTest = React.createClass({
  getInitialState: function() {
    return {
      showImageOne : true, 
    };
  },
  render: function() {
    // [NEW] Logging out moduleVar
    console.log("TestModuleVar.moduleVar is: " + TestModuleVar.moduleVar);
    return (
      <ViroScene>
        <ViroImage position={[0,0,-1]} source={this.state.showImageOne ? imageOne : imageTwo}
          onClick={this._onImageClick} />
        <ViroButton position={[.5,-1,-1]} source={imageOne} onClick={this._onImageOneClick}/>
        <ViroButton position={[-.5,-1,-1]} source={imageTwo} onClick={this._onImageTwoClick}/>
      </ViroScene>
    );
  },
  _onImageClick() {
    // [NEW] Changing moduleVar
    TestModuleVar.moduleVar = "barfoo";
    this.setState({
      showImageOne : !this.state.showImageOne
    })
  },
  _onImageOneClick() {
    this.setState({
      showImageOne : true
    })
  },
  _onImageTwoClick() {
    this.setState({
      showImageOne : false
    })
  },
});

module.exports = SwapImageTest;

TestModuleVar.js

/*
 * TestModuleVar.js
 */

var moduleVar = "foobar";

exports.moduleVar = moduleVar;