Lots of excitement at the Adobe booth at Mobile World Congress in Barcelona. Our announcement about Flash Player 10.1 and AIR for mobile devices is definitely buzzing!

Photos shot with a Google Nexus One.

After a very successful and fun tour though the UK, SOTR is now going to mainland Europe. Most of you  know that my love for ColdFusion is growing with every project I do using it. I think you can really only appreciate ColdFusion after getting a taste of it and SOTR is the perfect place to get that taste. With SOTR Europe being a free event, there really is no excuse to not be there. ;-)

Hope to see you in Munich, Zurich, Milan, Amsterdam, Brussels or London!

More info and free registration on http://www.scotch-on-the-rocks.co.uk

This is probably the most important step to take when you are building your application and it should probably be the first thing you do. Let’s say someone found a bug in your application and you fixed it in a newer version. How are you going to tell users about that bug-fix if you don’t have an update mechanism in place? AIR has everything on board to make updating applications a breeze, both for you and the user of your application.

Whenever my application starts, it’s going to load an XML file from my server. That XML file describes the version I have on my server and I even added some release notes. This XML file can be structured any way you want it to be and can hold all the information you want in there. Working with XML files in AS3.0 and Flex has become a breeze compared to how it used to be. So no more firstChild.childNode[3].grandChild.bastardChild.attribute.version.

My application version XML file looks like this:
<?xml version="1.0" ?>
<application>
<info version="2" downloadurl="http://localhost/version2.air" />
<releasenotes>
<![CDATA[Fixed some bugs in this version]]>
</releasenotes>
</application>

Loading an XML file in Flex, is as simple as this one line of code:
<mx:HTTPService
id="appversion_xml"
url="http://localhost/onAIR/appversion.xml"
showBusyCursor="true"
resultFormat="e4x"
result="checkForUpdate()"/>

This creates an XML object with the name “appversion_xml”. Whenever the server sends back a result, the result event is fired which calls my checkForUpdate() function. I even show a little busy cursor to show the user that there’s something happening. E4X is the preferred result format. Now to load the XML file when my application starts, I created an init function.

private function init():void
{
	appversion_xml.send();
}

This gets called when my application is ready. Just add this attribute to your WindowedApplication node in Flex.

creationComplete="init()"

So the next thing you need to do when your XML file is loaded, is check if the version on your server is different from the one you have installed.

var descriptor:XML = NativeApplication.nativeApplication.applicationDescriptor;
var ns:Namespace = descriptor.namespaceDeclarations()[0];
currentVersion = descriptor.ns::version;

This would get the version number of the version you have installed. This actually refers to your application descriptor XML file. The application descriptor file gets included in your application when you build it and is accessible through NativeApplication.nativeApplication.applicationDescriptor.

The version number that I got back from the server will be available in:

appversion_xml.lastResult..info.@version;

Now I need to add a quick note here. The application version designator can be anything you want it be. It can be just a simple number but it can just as well be something like v3.79.3.222.beta.1.5.67.78. However, I find it a lot easier to use just plain and simple increasing numbers. These are a lot easier to compare to each other and thus make it a lot simpler for you to code.

if(Number(updateVersion) > Number(currentVersion)) {
	//update available
}

Now that’s a lot easier than having to create your own logic to compare your version designators.

So now that we know the version on my server is newer than the one I have installed so we have two options. You could just do the update without any user intervention, or you might want to let the user known that there is an update available and let him decide what he wants to do. In my demo application, I popup a little utility window that also displays the release notes from the XML file but you can let the user know about the options in however way you see fit.

We’re almost there. Now that we know the user wants to update the application we can go ahead and do so.
So the first thing we need to do, is download the new update to the local machine. Since we are using AIR we have access to the desktop and so we can do this automatically. In the code below, I create a new instance of a URLStream and attach an eventListener to it. Whenever the URLStream is done, it’s going to execute the code to store it on the user’s machine. In this case we are going to store the update in the applicationStorageDirectory and rename it to update.air. Next we create a new instance of the Updater class and call it’s update method specifying the path to our update and its version number.

private function downloadUpdate(file:String):void
{
   downloadStream = new URLStream();
   downloadStream.addEventListener(Event.COMPLETE, function(evt:Event):void {
      myUpdateWin.statusText = "Downloading and installing the update";

      var appData:ByteArray = new ByteArray();
      downloadStream.readBytes(appData, 0, downloadStream.bytesAvailable);

      var updateFile:File = File.applicationStorageDirectory.resolvePath("upgrade.air");
      var fileStream:FileStream = new FileStream();

      fileStream.open(updateFile, FileMode.WRITE);
      fileStream.writeBytes(appData, 0, appData.length);
      fileStream.close();

      var appUpdate:Updater = new Updater();
      appUpdate.update(updateFile, updateVersion);
   });
   downloadStream.load(new URLRequest(file));
}

The update method of the Updater class will close the application, launch the AIR installer to install the update and then relaunch the application. All without any intervention from the user! Completely transparent and easy for the end user.

That’s how easy it is to do it but to make it even easier, we’ve just released an update framework to simplify things even more. This framework works for both Flash/Flex based applications and Javascript/HTML based apps.

You created your AIR file… so now what? The easiest thing to do is to upload the file to your server and put a link to it on your website. But this is not very user-friendly for whoever is going to download and install your application. In some cases, when your server isn’t configured to handle AIR files, it may even fail altogether. That’s why we created the concept of install badges. Install badges are basically a small Flash application that handles download and install in such a way that it becomes very easy for the end user to install your application.

There are 3 different flavors of the install badge: The standard version, the “currently in beta” version and the custom install badge.

The standard install badge is part of the AIR SDK. If you download and extract that zip file, there’s a folder called samples that includes a ready-to-go sample. Just change some parameters in the source of the html, upload the files and your AIR file to your server and you’re done. I have to be honest and tell you that I don’t really like the standard badge. It’s fine if you just want a simple install badge but the beta badge is so much better.

The beta badge is available on Adobe Labs. It is actually created by Grant Skinner. The first thing you notice when you launch the sample, is that it has a much cooler/smooth look. But this badge also has a bunch of extra features that the default badge doesn’t have. For one, this badge can determine if the application is already installed and then prompt the user to launch the application right from within the browser. It also detects if the user has the correct version of the runtime installed; if not, it will offer to download it. This badge also allows you to add a little bit of support information when the user clicks on the question-mark icon. But my favorite feature is that this badge uses SWFObject which is my preferred way of adding SWF content to a web page. If you compare the source of the default and beta badge, you’ll see that SWFObject and the way it handles FlashVars is a lot more readable compared to the name-value pairs in the default badge.

The third option would be to build your own install badge. Don’t worry… you don’t have to start from scratch. The sources for both the default and beta badge are available so you can use these as the basis for your own. It’s as simple as that ;-) The great thing is that this can be anything you want to it to be and can have all the features you want it to have ’cause well… you are building it. If you want to ping your server whenever someone starts the install of your application for instance, that is absolutely possible.

First of all, why is signing an application important? Easy. When your application is unsigned or signed with a self-signed certificate, the user will get two red icons on the install screen. The first one is related to your code signing certificate. It’s telling you that the “publisher is unknown” which is very normal since we have no idea who actually signed this application.

When you do get a code signing certificate and sign the application with it, the icon will turn green or in some cases yellow. The yellow icon will appear when you are using the file I/O API.

So where do you get a code signing certificate? Well, maybe you already have one. If you already bought one to sign Java or Cocoa applications for instance, chances are that this certificate is 100% compatible and you can use that. To make sure, check that your certificate is a Class 3 code signing certificate and you should be ready to go. If you don’t have, there’s a number of companies like Thawte.com that actually sell these. But if you upload your application to the Adobe AIR marketplace, you may get a complimentary code signing certificate from us. More info here.

I’m mainly using Flex for AIR development but the workflow is very similar in Flash or Dreamweaver. In case of Flex, you are actually going to build a release version of your application. To do that, you click the “export release build”-button. That will popup a little wizard window. In the first window, you can specify where you want to save your .AIR file. In this case, I’m saving it on the desktop.

When you click “next”, Flex will ask you to specify which digital certificate you want to use. If you don’t have one but still want to build a .AIR file for testing, click on the “create” button. When you fill out all the details of that form, you can save that self signed certificate so you don’t have to fill out that form every time. I saved mine in my home folder. Once you have created it, you can easily reuse it by just entering your password.

If you already have a code signing certificate, you can browse to the location you saved it to use it. Click “finish” and your AIR file is going to be baked. That’s it.

Some 2000 kilometers (about 1300 miles), about 31 hours on 5 different trains and about 10 battery charges later, we arrived in Prague today. Well… Actually, I’m writing this on the train from Warsaw to Prague so we’re not actually there yet and we still have about 5 hours left on this train but I can’t actually post this until we do arrive in Prague. But anyway, I thought this would be a great time to look back at last week.

We started this leg of the tour in Stockholm (A). I really love Stockholm. Everyone is so nice there and the city is beautiful. Oh and cinnamon rolls are a national speciality and as some of you know I really like cinnamon things ;-) Jag alskar Stockholm! The event was in an old brewery right by the river. I really like these old buildings with exposed structures etc. After the event, Enrique, Melissa (from the event company taking care of all the logistics for the tour) and I went to a really nice fish restaurant right around the corner from our hotel. The concierge of our hotel actually suggested this restaurant and I have to say, he has great taste! If you ever find yourself in Stockholm, go check out Wedholms fisk restaurant.

The next morning… oh wait… I think it was still officially night ’cause our train left at 6am so we met in the lobby at around 5:30. That kinda hurt… and we all knew this was going to be the longest trip from the tour. A train from Stockholm to Berlin via Copenhagen (B) and Hamburg (C). It should have ‘only’ taken us 12 hours to get to Berlin but because the first train had a 30 minute delay, we actually missed our connection in Copenhagen. We spent 3 hours in Copenhagen Central station. Actually… We spent it at the O’Reillys sports bar in the station ;-)

At the coast in Denmark, the train drove on to a ferry and we crossed the Baltic sea enjoying a breeze of fresh air op the top deck of this ferry. Really nice to get out for a while. I think we finally arrived in our hotel in Berlin (D) at almost midnight… 18 hours after we left Stockholm. I guess I don’t need to explain that everyone was dead tired…

Next morning was yet another early morning wakeup call to go to the venue. Actually, I should be honest and tell you that Mike Chambers (our road-manager ;-)) did tell me that I could sleep a little longer since my session was in the afternoon but I knew that Benjamin Dobler and Marco Kaiser were joining us in Berlin and I wanted to welcome them early. Benjamin showed us some new stuff he’s currently working on for parleys.com. He’s actually building a complete publishing solution for Parleys where you can just add videos, slides etc and it even does PPT conversion. Amazing work! It was great to meet Marco for the first time and it was even better that I could ask him about some feature requests for the next version of Twhirl. Looking forward to that next version Marco! Now let’s hope that Twitter becomes a bit more stable and useable again. That evening, Kevin Hoyt, Lee Brimelow, Danny Dura and I went to a typical German restaurant American diner right on Potsdammer Platz. Great burgers and great steak. Some of us would go right back although that may also be because of the pretty waitress ;-)

Thursday morning, we took the train to Warsaw. A few minutes after we crossed the Polish border, the train stopped and when we looked outside, we could actually see our locomotive taking off without the train. Just a little bit strange but luckily a few minutes later, a new locomotive pulled up and we were back on route.

The event in Warsaw (E) was at the Olympic Center. The Olympic committee did a great job here. As in Stockholm and Berlin there were only a few empty seats in the room and the crowds were really great and responsive. In the evening all of us went the old town for dinner. While we waited for our food (which took a bit longer than it should have), Danny told us that the square we were on is actually a Unesco protected site. But it felt kinda fake to me and that’s completely normal since they had it completely rebuilt based on sketches and original plans. Some of us ordered boar for dinner. I never had boar so I ordered it too. Sadly it was way overcooked and apparently not really how it should be. Guess I’ll have to try it again somewhere else.

So here we are sitting on a train to our next destination, Prague (F). I’ve never been there but I hear it’s really nice. Tomorrow (Sunday), we actually have a day off so you can bet I will be in tourist mode tomorrow and take lots of pictures.

At this moment there are only 37525 minutes left for you to register for the second leg of the onAIR tour. That’s 26 days before we start travelling from northern to southern Europe. In case you forgot, we are doing this onAIR tour by train and there are some pretty challenging routes we have to take this time. We start in Stockholm on June 2nd and end in Milan on June 13th. I don’t know if my evangelist buddies have already seen this but our first train ride, from Stockholm to Berlin, is going to be 15 hours. Our train-ride from Madrid to Paris was a good rehearsal but this one is even longer. I’m already stacking up on extra batteries etc and I’m gonna make sure my 3G card works. Maybe we should carry a power generator on the train so we don’t run out of juice :-)

I remember that in one of his videos, Lee Brimelow says that “Europe isn’t that big”. I’m pretty sure he’s gonna change that statement by the end of this tour.

Again looking forward to this tour… We are visiting some really beautiful cities, some of which I’ve never been to myself. We’re doing Stockholm, Berlin, Warsaw, Prague, Munich and Milan. If you weren’t aware of this yet, we are also giving away a bunch of goodies and for the second part of the tour we’re getting everyone a copy of the Adobe AIR for JavaScript Developers book and a copy of the RIA ActionScript 3 printed reference guide. They weren’t ready in time to take on the first leg but don’t worry if you came to the first part of the tour, you’ll receive an email soon with details on how you can get them as well. In the meantime, you can download these books.

Oh… Did I already mention the tour is almost sold out? So if you haven’t registered yet (it’s free by the way), now is the time to do so! Register at onair.adobe.com. Hope to see you in Stockholm, Berlin, Warsaw, Prague, Munich or Milan!

We just arrived in Paris (our second stop for the onAIR Tour Europe) after what must have the longest train ride ever. I don’t think I’ve ever been on a longer train ride in my entire life. So… Imagine that feeling when you just came off a really fast rollercoaster ride. You step out of the car and you still feel the earth move under your feet. Now imagine doing that for 12 hours and you get a bit of an idea how some of us are feeling right now. Like Kevin Hoyt Twittered earlier, it feels like the whole building is moving.

Most of use Twittered as much as we could on our cellphones… right up until those batteries died too. Mike Chambers even thought about coding in the toilet since that was the only place where there was a powerplug on the train.

Anyway, if you want to keep up to date with our escapades on the road in Europe, here’s some links to help you:

• Lee Brimelow [Twitter] [Flickr]
• Mike Chambers [Twitter] [Flickr] [YouTube]
• Andre Charland [Twitter] [Flickr]
• Daniel Dura [Twitter] [Flickr]
• Kevin Hoyt [Twitter] [Flickr]
• Serge Jespers [Twitter] [Flickr] [YouTube]
• Ryan Stewart [Twitter] [Flickr] [YouTube]
• onAIR: Live from the tour

Just over a week ago, I asked you guys to register for the Brussels stop of the onAIR tour because we (us Belgians) were in last position. I am happy to announce that we actually doubled the registrations last week and have actually sold out now! So thank you all for creating the buzz and for registering! I’m looking forward to see you all there!

Actually, all events in the first leg of the tour are now sold out but we have expanded the capacity for the Paris event. Paris is only about an hour and a half from London and Brussels with the train so that may be an option if you couldn’t make it to those events. And there’s also the second leg of the tour which starts in Stockholm on June 2nd.

The tour starts in exactly 10 days now and I have to say that I’m really looking forward to it. There’s something very appealing to taking the train all across Europe with your fellow evangelist friends and I’m sure we’ll have lots of fun and a ton of great stories to tell and we all have Flip camera’s in our backpack so I’m pretty sure there will be also be a lot of incriminating video footage to share :D

UPDATE: Paris has sold out again.

I know… The title is a bit dramatic but really… Being Belgian, it obvious that I would like to change that. So, if you haven’t registered for the free onAIR event in Brussels, now may be a good time to do so :-) So head on down to the registration page to register for the April 7th event with Mike Chambers, Kevin Hoyt, Danny Dura, Andrew Shorten, Oliver Goldman, Andre Charland, Lee Brimelow, myself and special guests Peter Elst and Nicolas Lierman.

Check out the full schedule of the day. Hope to see you there!