Simple Titanium Commonjs Example

app.js

var MainWindow = require('MainWindow');
var mainWin = new MainWindow();
mainWin.open();

BarWindow.js

function BarWindow() {
	var self = Ti.UI.createWindow({
		backgroundColor:'#f0f0f0',
		layout:'vertical'
	});
	
	var lbl = Ti.UI.createLabel({
		text:'Bar Window',
		color:'#000',
		top:20
	});
	lbl.addEventListener('click', function() {
		self.close();
	});
	self.add(lbl);
	
	var btnFoo = Ti.UI.createButton({
		title:'Open FooWindow',
		top:25
	});
	btnFoo.addEventListener('click', function() {
		var FooWindow = require('FooWindow');
		var fooWin = new FooWindow();
		fooWin.open();
	});
	self.add(btnFoo);
	
	return self;
};
module.exports = BarWindow;

FooWindow.js

function FooWindow() {
	var self = Ti.UI.createWindow({
		backgroundColor:'#dfdfdf',
		layout:'vertical'
	});
	
	var lbl = Ti.UI.createLabel({
		text:'Foo Window',
		color:'#000',
		top:20
	});
	lbl.addEventListener('click', function() {
		self.close();
	});
	self.add(lbl);
	
	var btnBar = Ti.UI.createButton({
		title:'Open BarWindow',
		top:25
	});
	btnBar.addEventListener('click', function() {
		var BarWindow = require('BarWindow');
		var barWin = new BarWindow();
		barWin.open();
	});
	self.add(btnBar);
	
	return self;
};
module.exports = FooWindow;

MainWindow.js

function MainWindow() {
	var self = Ti.UI.createWindow({
		backgroundColor:'#fff',
		layout:'vertical'
	});
	
	var lbl = Ti.UI.createLabel({
		text:'Main Window',
		color:'#000',
		top:'20'
	});
	self.add(lbl);
	
	var btnFoo = Ti.UI.createButton({
		title:'Open FooWindow',
		top:25
	});
	btnFoo.addEventListener('click', function() {
		var FooWindow = require('FooWindow');
		var fooWin = new FooWindow();
		fooWin.open();
	});
	self.add(btnFoo);
	
	var btnBar = Ti.UI.createButton({
		title:'Open BarWindow',
		top:25
	});
	btnBar.addEventListener('click', function() {
		var BarWindow = require('BarWindow');
		var barWin = new BarWindow();
		barWin.open();
	});
	self.add(btnBar);
	
	return self;
};
module.exports = MainWindow;