Hey everyone

We’re looking for some skilled PHP developers to help us innovate with and improve on AMFPHP. If you think you’ve got the goods to help us get this project insanely powerful (but still simple and easy to use), drop us a line!

• Ariel Sommeria-klein – Project Lead (ariel@amfphp.me)
• Danny Kopping – Development Lead (danny@amfphp.me)

In the process of running your own software development business – or any type of business for that matter, you need to keep on top of things; dropping the ball for a day could land you in some trouble. Small-to-medium software development companies (consisting of between 1 and 30 people for example) are going to require the following services:

• Email
• Source-code/Project/Time management
• Document management
• Meeting management
• Billing & accounting
• Internal & external communication (Instant messaging, VOIP)
• Website Hosting

If you, as a business owner or manager, have the power to control all of these services from your browser then you will have the peace of mind knowing that you’re on top of things.

Luckily, in this incredible world where Software-as-a-Service (SAAS) is booming at an astounding rate, keeping track of your business comes at a minimal cost: +- $30! Most of these services that i will talk about are web-based, which means that all your data will be stored offsite. That last sentence will strike fear into the heart of any business manager – if he/she is ignorant about the inherent value of offsite storage and SSL-encryption. The fact is, storing your data offsite is a smarter option; offsite storage means that your data is hosted outside of your physical office space, which means that no matter what natural/unnatural disaster strikes your premises, your data – the fundamental part of your business - is safe. If you also make sure that these web-services communicate through an encrypted connection, then there really is nothing to worry about.

Let’s look at how we can get the most bang for our bucks with some of the best online tools available…

Email

At the heart of every software development business is email… no suprises there. What will surprise you is the massive bill you’ll be happily stuck with by Microsoft or IBM if you use their Exchange or Lotus Notes services. There is a solution though… Enter Gmail from Google. I’ve been using Gmail now for about a year, and i must say that it’s a tremendous improvement over Microsoft Outlook. Here’s why i love Gmail:

• The ability to add as many POP/IMAP accounts to your Gmail account – consolidating all your email into one sleek interface. Not only can it pull from all of your other POP/IMAP accounts, but you can also send from them too! I’ve got 5 email accounts all running through Gmail and i can send email from any one i like.
• Amazing spam filter
• Integrated chat
• Labels & filters – you can customize Gmail to automatically label emails by search terms. For example, i’m the development leader on an open-source framework called AMFPHP. If i send or receive an email containing “amfphp”, it gets labelled as “AMFPHP” and neatly filed with all my other emails matching that search query.
• Outside access – i’ve got an HTC Hero which has a Gmail application installed, which means i can access my Gmail from my phone
• Integration with Google Contacts, Google Docs & Google Calendar
• > 7GB storage!
• Extremely fast search (c’mon, this is Google)

Cost: Free! (or $50/user/year if you want to use the business package with 25GB of storage per user)

Source-code/Project/Time management

This is by far my favourite and most valued service that i subscribe to: CodeBaseHQ. Using CodeBaseHQ has changed the way that i develop software. It gives me the freedom to work the way i want and feel comfortable knowing that support is just an email away (with super-fast response times and helpful service). Here’s why I love CodeBaseHQ:

• Great variety of Source-code Management (SCM) repository systems – Git, Mercurial and (my personal choice) Subversion
• Built-in project management features to help me and my clients keep track of bugs & feature requests
• Very slick and customizable interface – easy to understand and use
• Secure, well-managed code storage
• Very helpful support team
• Actively in development – new features being added all the time
• Reasonably priced
• Time-tracking built right in

Cost: $8/month for smallest package, $32 for more serious usage

Document Managament

You guessed it… Google Docs. Why would you want any other system? Google Docs makes it really easy to view and collaboratively or individually edit documents of most formats. Google Docs allows you to upload files of any type and has some crazy features like built-in integration with Google Translate to facilitate translation from right there in your document! Here’s why i love Google Docs:

• Upload files of any type
• View most document formats (PNG, JPG, GIF, PDF, DOC, XLS, PPT)
• Collaboratively edit documents (but you can edit on your own if you like )
• Built-in dictionary and translation
• Creation of a wide variety of document types (text documents, spreadsheets, presentations, forms, drawings)
• 1GB of storage (or 20GB for a minuscule $5 per year)

Cost: Free! (or $50/user/year if you want to use the business package)

Meeting Management

I know i’m starting to sound like a Google fanboy, but Google Calendar is the shit (pardon my French). Apart from doing just what you want a calendar to do (and no less, but a little extra), it’s really well thought-out and easy to use. Once again, Google has outdone themselves and allowed you to sync your calendar to a wide variety of applications, and i use my calendar on my HTC Hero (a Google phone, wow – maybe i am a fanboy) to manage all my meetings knowing that all my appointments are safely stored online and accessible anytime. Here’s why i love Google Calendar:

• Clear, concise interface – very sleek and simple to use
• Sensible interface for creating/edit appointments – drop and drop, expand and contract
• Multiple calendars (personal, work, etc)
• Integration with your country’s national holidays (and religious holidays too)
• Task management built in
• Collaboratively invite people to an event or appointment and keep track of who’s attending or not
• Sync with many clients: Google Chrome, Thunderbird, Outlook, Entourage, iPhone, Android
• Extremely fast search – duh
• Free notifications – email, pop-up reminder, SMS (also free)!!

Cost: Free! (or $50/user/year if you want to use the business package)

Billing & Accounting

Freshbooks, what a service! Freshbooks is fantastic online service which allows you to create customizable estimates and invoices – all accessible via the web. It’s a very clear and simple application which makes invoicing and cost-estimating really simple, and it makes you look very professional. With over 1 000 000 subscribers to their service, you can be assured that this service is top-notch. Here’s why i love Freshbooks:

• Create your invoices online
• Simple, sleek and professional interface that you and your clients can easily understand
• Fast, reliable and well supported by a fantastic support team
• Actively developed – new features added often
• Manage recurring and once-off payments
• Multiple currencies
• Built-in accounting
• Reasonably priced

Cost: $19 / month (more options available)

Internal & external communication (Instant messaging, VOIP)

If you don’t use Skype, then welcome to planet Earth. Skype is a brilliant way to connect to your team and friends. Skype allows you to do instant messaging, voice-calls (free for Skype-to-Skype) and video-calls (Skype-to-Skype). I’ve been using Skype for years now and i couldn’t live without it. Skype has some great options available for business usage, and i suggest you check them out. Here’s why i love Skype:

• Ubiquitous – a good majority of businesses use Skype which means that you can save a lot of money by calling Skype-to-Skype
• Simple, clear interface
• Extensible
• Cost-effectively structure your business telecommunications

Cost: Free! (with business options & Skype-to-phoneline credits available)

Website Hosting

When it comes to web-hosting, my personal choice is VPS.NET. VPS.NET is a wonderful service offering that allows you to create a Virtual Private Server in one of VPS.NET’s many datacentres in the UK & US, and do with it what you like! When you sign up with VPS.NET, you purchase a number of “nodes” to use; each “node” consists of 0.4 GHz processing power, 376Mb of RAM, 10Gb storage and 250Gb bandwidth. As you buy more and more nodes they become cheaper, and you can tack on extra IP addresses, server monitoring software and automated backups. You can use your VPS to host websites, act as an online storage location, whatever you like! Here’s why i love VPS.NET:

• Simple, sleek user interface
• Very competitive service offering and pricing
• Excellent and knowledgeable support staff available 24hrs/day
• Actively developed – new features added all the time
• Wide variety of operating systems to choose from to install on your VPS
• Wide variety of additional services and features
• Reliable

Cost: $20 / node / month (with decreasing price as you buy more nodes)

Summary

As i’ve demonstrated, the tools are readily available to manage your development business effectively while sitting on your rump. The service offerings out there completely enthrall me and i’m delighted to have such a range of efficient tools at my disposal for a minimal cost per month.

Have i missed anything? Got a better solution? Pop me a comment

WireframeSketcher is an Eclipse plugin which offers a similar feature-set to Balsamiq Mockups, although personally i prefer WireframeSketcher. Firstly, it plugs right in to my current workflow in Eclipse – that already wins it many points in my book! Aside from that, the plugin feels a lot more stable than Balsamiq and offers a few interesting features, such as:

• Wiki syntax formatting on all supported controls
• Screens vs Masters vs Storyboards
  • A Screen is a view that you can build
  • A Master is a reusable component that can be used in Screens
  • A Storyboard is made up of a collection of Screens
• Well thought-out presentation mode allowing you to jump between screens

All in all, i like the way it’s structured; i like that you can create separate files for logically separate areas of your whole application mockup and bring them together in a storyboard. I’ve used it on a couple practical examples that i was planning to do, and it feels comfortable and usable.

If you’re developing your a Java application with SWT, there’s also a neat plugin to export your wireframes as SWT code

Maybe an MXML export feature is on the cards too! That would certainly be wonderful…

What is Aerial CMS?

Aerial CMS (named Aerial because it was the first word i could think of with “RIA” in it) is a simple content management framework. I decided to rethink the concept of a content management system, because – the way I see it – CMSs these days are about content management AND content presentation. I think that these two massive areas of development & design need to stay very far away from each other. They are like brother and sister to us now, but sometimes – when stuck in a room together for so long – they breed and the results are disastrous (on top of being scandalous!).

Design Philosophy

Look at how the MVC (Model View Controller) pattern came about: software engineers found that separating application logic from presentation from data has serious design benefits. Now, i’m not attempting to bad-mouth all the incredible efforts of the CMS developers… I’m saying that for Rich Internet Application development, it really becomes a chore to use systems like Drupal or Symfony because they were not meant to be used in that way. They do what they do superbly well, but for RIAs they fail to impress me.

Aerial CMS has been built from the first line of code for optimized Rich Internet Application development. It focuses only on content management and development tooling, and wants nothing to do with how you present the data. It’s certainly a change from the standard model, and i’m convinced about how I want to develop my RIAs, but that’s why i’ve put out this early release – to see if you all agree with me. This CMS still has a very, very long way to go; it works well for most situations but the tools haven’t been developed yet.

Technology

Aerial has been built on two very well established and loved open-source frameworks, namely AMFPHP 1.9 and Doctrine 1.2.1. The Aerial framework is built for compatibility with PHP 5 only. Aerial enforces no rules upon you when you get down to developing your back-end code, but it does stick to Doctrine’s method of generating database tables and models. In essence, once you’ve set up your database schema, you can do whatever you like you can plug into Doctrine’s API or you can write your own code; it really gives you the freedom to code the way you’re comfortable with.

Tutorials and Videos

I’ve made a Getting Started video to get you familiar with the framework and i’ll be writing a series of tutorials in the Wiki section of the Google Code page for Aerial CMS. I’ve also got plans for a couple more video tutorials, so keep checking the site for updates or follow me on Twitter (@dannykopping).

Comments, Suggestions, et al

I’d love to hear what you have to say (as long as it’s in English – being monolingual sucks)! I’m very open to suggestions, any offers to help contribute would be welcomed and all constructive criticism is encouraged!

As any developer who has ever dipped their toes into the murky pond that is cross-domain configuration with Flash will tell you, it is quite a confusing and somewhat aggravating task to accomplish. In this post, I’m going to demonstrate how you can control access to your APIs from Flash applications by dynamically generating crossdomain.xml files that work the same as static crossdomain.xml files.

But before we go any further, what the hell is a crossdomain.xml file?

The definition of a cross-domain configuration file is (taken from http://www.senocular.com/pub/adobe/crossdomain/policyfiles.html):

A cross-domain policy file is a XML document that grants a web client, such as Adobe Flash Player, permission to handle data across multiple domains. When a client hosts a content from a particular source domain and that content makes requests directed towards a domain other than its own, the remote domain would need to host a cross-domain policy file that would grant access to the source domain allowing the client to continue with the transaction. Policy files grant read access to data as well as permit a client to include custom headers in cross-domain requests.

Essentially what this means is that if you have a Flash application and you need to pull data (other than images or video) from a domain which is not the domain of your hosted application, you will need to place a crossdomain.xml file on the server you are requesting data from.

The configuration file needs to be placed in the webroot of the server; you can have a look at some of the more popular sites’ crossdomain.xml files:

• http://youtube.com/crossdomain.xml
• http://twitter.com/crossdomain.xml
• http://facebook.com/crossdomain.xml

This post is not a “how-to” on crossdomain.xml files unfortunately: for that, you can visit http://www.adobe.com/devnet/flashplayer/articles/cross_domain_policy.html – a great article by Lucas Adamski.

The Problem

You would like to control access to your application’s API based on a database table, for instance:

You have an application that serves up a list of products like Amazon.com to be made available via AMF requests (could be a REST-based architecture, SOAP, etc). You have a service offering whereby Flash/Flex application developers can register with your company to be allowed to access this wonderful API. You charge a set price per year for your service and you keep a database of authorized subscribers. At this stage, you can either allow any domain to access your API by using the following crossdomain.xml file:

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<!DOCTYPE cross-domain-policy SYSTEM "http://www.adobe.com/xml/dtds/cross-domain-policy.dtd">
 
<cross-domain-policy>
   <site-control permitted-cross-domain-policies="master-only"/>
   <allow-access-from domain="*"/>
</cross-domain-policy>

The problem with this configuration is that any domain can send requests to your API from their Flash applications, and for obvious reasons this is not such a great idea.

The other (more secure) option would be to manually stick in each subscriber’s domain name into the crossdomain.xml file as follows:

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<!DOCTYPE cross-domain-policy SYSTEM "http://www.adobe.com/xml/dtds/cross-domain-policy.dtd">
 
<cross-domain-policy>
   <site-control permitted-cross-domain-policies="master-only"/>
   <allow-access-from domain="example1.com"/>
   <allow-access-from domain="example2.com"/>
   <allow-access-from domain="example3.com"/>
</cross-domain-policy>

With the above configuration, you will start running into major headaches your subscribers either start cancelling their accounts or fail to pay in full. You will manually have to go and remove their domains from the configuration each time.

The Solution

When Flash applies a security policy like this, it automatically looks for a crossdomain.xml file on the requested server in the webroot. We can use a nifty combination of Apache rewriting and a PHP script to dynamically generate a list of authorized domains.

Apache Configuration

We want Apache to listen for an incoming request for our crossdomain.xml file, but instead of serving the XML file, we want to process a PHP script called generate-config.php to generate our configuration options. This example is quite simplistic, and I encourage you to take this further with whatever rules your application may require.

We are going to create a .htaccess file in the webroot of our server with the following contents:

RewriteEngine On
RewriteCond %{REQUEST_URI} crossdomain.xml
RewriteRule ^crossdomain\.xml$ generate-config.php [L]

This will present the output of our generate-config.php file as the contents of the crossdomain.xml file – essentially using another file’s content in place of another.

PHP & MySQL

In our generate-config.php file, we are going to:

1. Connect to a database
2. Run a SQL query that will return a list of subscribers
3. Iterate through our list and add them to our XML output
4. Echo the XML output back to Apache

First, create a database called crossdomain_test and then run the following SQL query to create our subscribers table:

CREATE TABLE IF NOT EXISTS `subscribers` (
  `ID` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL,
  `domain` varchar(255) NOT NULL,
  `active` tinyint(1) NOT NULL DEFAULT '1',
  PRIMARY KEY (`ID`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;

Insert a couple of test rows:

INSERT INTO `subscribers` (`ID`, `name`, `domain`, `active`) VALUES
(1, 'YouTube', 'youtube.com', 1),
(2, 'Twitter', 'twitter.com', 1);

Now we’re going to create our generate-config.php file in the webroot:

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<?php
	// create our config skeleton according to the crossdomain.xml rules
	$xml = '<?xml version="1.0"?>
<!DOCTYPE cross-domain-policy SYSTEM "http://www.adobe.com/xml/dtds/cross-domain-policy.dtd">
<cross-domain-policy>
	<site-control permitted-cross-domain-policies="master-only"/>
</cross-domain-policy>';
 
	// create $config variable to hold our config data
	$config = new SimpleXMLElement($xml);
 
	// connect to MySQL and select database
	$conn = mysql_connect("localhost", "username", "password");
	mysql_select_db("crossdomain_test", $conn);
 
	// loop through all rows, and create xml nodes
	$res = mysql_query("SELECT domain FROM subscribers WHERE active = 1");
	while($subscriber = mysql_fetch_object($res))
	{
		$child = $config->addChild("allow-access-from", null);
		$child->addAttribute("domain", $subscriber->domain);
	}
 
	// echo back to Apache
	echo $config->asXML();
?>

If we navigate to the crossdomain.xml file in the browser, we should see:

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<?xml version="1.0"?>
<!DOCTYPE cross-domain-policy SYSTEM "http://www.adobe.com/xml/dtds/cross-domain-policy.dtd">
<cross-domain-policy>
	<site-control permitted-cross-domain-policies="master-only"/>
	<allow-access-from domain="youtube.com"/>
	<allow-access-from domain="twitter.com"/>
</cross-domain-policy>

and if we delete one of the records out of the table (try deleting YouTube), and navigate to that page again, you’ll see:

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<?xml version="1.0"?>
<!DOCTYPE cross-domain-policy SYSTEM "http://www.adobe.com/xml/dtds/cross-domain-policy.dtd">
<cross-domain-policy>
	<site-control permitted-cross-domain-policies="master-only"/>
	<allow-access-from domain="twitter.com"/>
</cross-domain-policy>

And that’s it! Not too difficult at all

A Workaround for all frustrated developers consuming REST services

As a side-note, if you ever encounter a site that you need to pull data from and they do not have a crossdomain.xml file, all you have to do is write a simple “proxy” file with PHP (or whichever language you choose) that will accept one parameter (the URL to be called) and send the results back:

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<?php
 
	$url = $_GET["url"];
	echo file_get_contents($url);
?>

Make sure that this proxy file is sitting in your domain though, or a domain with a crossdomain.xml file present.

Now, just because I received a free license to review the software it does not mean that will not point out the egregious problems that I find with the software, nor will I ramble on about how fantastic it is. All I will say is this: If you deal with clients often that have not got any creative done for a prospective project and are looking for Interface Design advice, this is the tool for you!

Onto the review…

Overview

Balsamiq Mockups is an AIR application built to help you mock up application interface designs in the timeframe of a (non-metric) “jiffy”. Since i’ve started using the application, i’ve put together numerous mockups for clients and always received good feedback. What Balsamiq lacks in extensibility it makes up for in sheer speed of use.
The application is well thought out and concise. No instruction manual or cerebral documentation necessary! As far as AIR applications go, this is one of the more advanced ones I’ve seen, and it certainly is a pleasure to work with. I wouldn’t go so far as to say it justifies a $79 price-tag, but it is well worth the loot.

Tooling and Extensibility

As far as tools go, the Balsamiq developers certainly went out of their way. Included in the application are over 75 user-interface components from Buttons to Charts to iPhones, as well as loads of icons that will provide the finishing touches on any rough cut. The components are all customizable, scalable and z-axis-orderable, and the keyboard shortcuts help you get the job done quite quickly once you’re comfortable with the application.

The application fails abysmally when it comes to extensibility; I would imagine that with an application like this, the developers should facilitate the downloading of custom component/icon packs, or even user-submitted ones. This could as quite an interesting angle to the application i feel. Another thing I wish it included was some sort of color palette to slightly adjust the components. I’m assuming that it wouldn’t be too much trouble to include a little color-transform slider to add a bit more dimension to the components for added visual cues.

Good thing i downloaded the latest version (1.6.67 released on 24th Feb 2010) before i started ranting about the absence of the spacebar-invoked panning functionality… Good job guys! Works great

Search, Export and Memory Usage

The search functionality of Balsamiq is intuitive and responsive; scanning through different UI elements is a breeze and makes the whole experience that much more impressive. Balsamiq offers exporting your mockups to both PNG (why not JPG?) and PDF (go Thibault!) and it usually exports the mockups without problems. I’ve noticed that when my mockups become quite intense, the application does begin to lag a little though, but i’m confident that the developers are looking into that for future releases.

Conclusion

All in all, this is an indispensable tool for the discerning web developer & designer. If you need to give your clients an idea of what you’re going to produce and you have limited time, give this application a shot. Thanks to the Balsamiq team for the great addition to my development ammunition!

Take the following services-config.xml file for example:

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<?xml version="1.0" encoding="UTF-8"?>
<services-config>
	<services>
		<service id="amfphp-flashremoting-service" class="flex.messaging.services.RemotingService"
				messageTypes="flex.messaging.messages.RemotingMessage">
			<destination id="amfphp">
				<channels>
					<channel ref="my-amfphp"/>
				</channels>
				<properties>
					<source>*</source>
				</properties>
			</destination>
		</service>
	</services>
	<channels>
		<channel-definition id="my-amfphp" class="mx.messaging.channels.AMFChannel">
			<endpoint uri="gateway.php" class="flex.messaging.endpoints.AMFEndpoint"/>
		</channel-definition>
	</channels>
</services-config>

As you can see, we’re setting the endpoint for our my-amfphp channel to gateway.php. What if you wanted to read that value into your Flex application? You could use the following code:

trace(ServerConfig.getChannel("my-amfphp").endpoint);

Check out the ServerConfig for more information!

I have teamed up with Ariel Sommeria-klein to revive the legendary AMFPHP project that spawned a whole new dimension of Rich Internet Applications. Together we have brought AMFPHP 1.9 out of beta and made it compatible with PHP 5.3. We have also completely rewritten the AMFPHP service browser and we have several improvements planned for AMFPHP 2.0.

If you would like to help contribute to this great open-source application, please contact us.

My test was conducted using Flex SDK 3.4.0.9271, Firefox 3.5.7 and Flex Builder Professional 3.0.214193

According to this page (under the Preloading modules heading), Adobe asserts the following:

When a module is loaded by the Flex application for the first time, the module’s SWF file is transferred across the network and stored in the browser’s cache. If the Flex application unloads that module, but then later reloads it, there should be less wait time because Flash Player loads the module from the cache rather than across the network.

Module SWF files, like all SWF files, reside in the browser’s cache unless and until a user clears them. As a result, modules can be loaded by the main application across several sessions, reducing load time; but this depends on how frequently the browser’s cache is flushed.

I found the above claims to be demonstrably false, or at least just plain inefficient…

Let me qualify this:
According to my tests (conducted with my Firefox browser cache turned both on and off), i found that the application’s memory usage keeps growing exponentially when switching between two loaded modules. There was a variance (as you’d imagine) when the browser cache was left on but nonetheless, the memory usage keeps growing steadily.

In the code sample below, I have extended the functionality of the mx.modules.ModuleLoader class, and added a Dictionary (with a little logic) to manage the (ostensibly) effective caching of previously loaded modules. I have not tested this class extensively, but all the tests that I conducted seemed to produce a significant memory and speed improvement.

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package
{
	import flash.display.DisplayObject;
	import flash.display.DisplayObjectContainer;
	import flash.utils.ByteArray;
	import flash.utils.Dictionary;
 
	import mx.events.FlexEvent;
	import mx.events.ModuleEvent;
	import mx.modules.IModuleInfo;
	import mx.modules.ModuleLoader;
	import mx.modules.ModuleManager;
 
	/**
	 * This class manages the loading, unloading and caching of Flex Modules
	 * This is a modified version of the mx.modules.ModuleLoader class
	 *
	 * @author Danny Kopping - danny@ria-coder.com
	 */
	public class CachedModuleLoader extends ModuleLoader
	{
		private var map:Dictionary = new Dictionary();
 
		private var _url:String = null;
		private var module:IModuleInfo;
		private var loadRequested:Boolean = false;
 
		public function CachedModuleLoader()
		{
			super();
		}
 
		override public function set url(value:String):void
		{
			if (value == _url)
				return;
 
			if (module)
			{
				module.removeEventListener(ModuleEvent.PROGRESS, moduleProgressHandler);
				module.removeEventListener(ModuleEvent.SETUP, moduleSetupHandler);
				module.removeEventListener(ModuleEvent.READY, moduleReadyHandler);
				module.removeEventListener(ModuleEvent.ERROR, moduleErrorHandler);
				module.removeEventListener(ModuleEvent.UNLOAD, moduleUnloadHandler);
 
				//module.release();
				module = null;
 
				if (child)
				{
					removeChild(child);
					//child = null;
				}
			}
 
			_url = value;
 
			dispatchEvent(new FlexEvent(FlexEvent.URL_CHANGED));
			removeAllChildren();
 
			if (_url != null && loadRequested)
			{
				if(!map[_url])
					loadModule();
				else
				{
 
					child = map[_url];
					addChild(child);
				}
			}
		}
 
		override public function get url():String
		{
			return _url;
		}
 
		override public function createComponentsFromDescriptors(recurse:Boolean = true):void
		{
			super.createComponentsFromDescriptors(recurse);
 
			loadRequested = true;
			loadModule();
		}
 
		override public function loadModule(url:String = null, bytes:ByteArray = null):void
		{
			if (url != null)
				_url = url;
 
			if (_url == null)
			{
				//trace("loadModule() - null url");
				return;
			}
 
			if (map[_url])
			{
				//trace("loadModule() - already created the child");
				return;
			}
 
			if (module)
			{
				//trace("loadModule() - load already initiated");
				return;
			}
 
			dispatchEvent(new FlexEvent(FlexEvent.LOADING));
 
			module = ModuleManager.getModule(_url);
 
			module.addEventListener(ModuleEvent.PROGRESS, moduleProgressHandler);
			module.addEventListener(ModuleEvent.SETUP, moduleSetupHandler);
			module.addEventListener(ModuleEvent.READY, moduleReadyHandler);
			module.addEventListener(ModuleEvent.ERROR, moduleErrorHandler);
			module.addEventListener(ModuleEvent.UNLOAD, moduleUnloadHandler);
 
			module.load(applicationDomain, null, bytes);
		}
 
		override public function unloadModule():void
		{
			if (child && contains(child))
			{
				removeChild(child);
				child = null;
			}
 
			if (module)
			{
				module.removeEventListener(ModuleEvent.PROGRESS, moduleProgressHandler);
				module.removeEventListener(ModuleEvent.SETUP, moduleSetupHandler);
				module.removeEventListener(ModuleEvent.READY, moduleReadyHandler);
				module.removeEventListener(ModuleEvent.ERROR, moduleErrorHandler);
 
				module.unload();
				module.removeEventListener(ModuleEvent.UNLOAD, moduleUnloadHandler);
				module = null;
			}
 
			if(map[_url])
			{
				delete map[_url];
			}
		}
 
		private function moduleProgressHandler(event:ModuleEvent):void
		{
			dispatchEvent(event);
		}
 
		private function moduleSetupHandler(event:ModuleEvent):void
		{
			// Not ready for creation yet, but can call factory.info().
 
			dispatchEvent(event);
		}
 
		private function moduleReadyHandler(event:ModuleEvent):void
		{
			child = module.factory.create() as DisplayObject;
			dispatchEvent(event);
 
			if (child)
			{
				var p:DisplayObjectContainer = parent;
				// p.removeChild(this);
				addChild(child);
 
				map[url] = child;//ModuleManager.getModule(_url);
				//trace(map + ":" + url + ":" + map[url]);
			}
		}
 
		private function moduleErrorHandler(event:ModuleEvent):void
		{
			unloadModule();
			dispatchEvent(event);
		}
 
		private function moduleUnloadHandler(event:ModuleEvent):void
		{
			dispatchEvent(event);
		}
	}
}

The usage of this class is exactly the same as the regular mx.modules.ModuleLoader class. I hope this helps!

Download this file: Download

**DISCLAIMER**
I know a bit about Flex modules from hours of obsessing over them, but i do not know everything. From my tests of the efficacy of the above code & explanation, i found that it reduces memory usage and increases the general usability of my Flex project; i could be very wrong on this topic, and if i am – please tell me. Maybe i’m just an idiot, but it seems to work…

Today i booted my machine, launched my snazzy Linux virtual machine, proceeded to start my XAMPP stack and mount my shared folder so that my Linux VM can communicate with my host OS (sigh) Windows… This works 99.9% of the time, but to my horror:

/sbin/mount.vboxsf: mounting failed with the error: No such device

FUCK! What now? So i google and google, but nothing works…

I’m now bashing my head in frustration against my desk, spilling my coffee and rubbing my blood-red forehead, but that didn’t help either… I try mount VBoxGuestAdditions via VirtualBox, nothing. Nothing, nothing, nothing! NOTHING!

By now i’m getting so irritated that i’m drinking coffee after coffee and smoking vociferously… and then…. -cue lightbulb- if you can’t take the horse to the water (mount VBoxGuestAdditions in Linux), pick the fucker up and dump him in there (download the fucking thing from Linux and run it from Linux). So, i dig around looking for the URL, eventually find it, mount the ISO file (help instructions on mounting an ISO file in Linux here), run the installation script, reboot and IT WORKS!! …and the children lived happily ever after.