I am at FITC Amsterdam this week, where I had a talk on Desktop Development with Adobe AIR. One of the things I showed was how to get notifications when new volumes / drives are added / removed to a machine. This could be useful if for example, you application needs to know when a new CD Rom or USB drive has been added or removed to the user’s system.

I am currently working on some code that runs in Adobe AIR where I need to access the File URL file:/ of a file located in the AIR app’s install directory. Normally, you could get the URI, by accessing the url property of the File object which will return a well formed, absolute file:/ URL. However, this doesn’t work for files located in the AIR app’s install directory. var f:File = new File("app:/icon.

I have been reading through Colin Moock’s Essential ActionScript 3 book, taking my time on each chapter to make sure I get the most out of it. I have been using ActionScript 3 pretty consistently for a couple of years (about a year before it was public), but I have been pleasantly surprised with how much stuff I am learning from reading Moock’s book. Anyways, I am currently reading Chapter 5 on Functions which among other things covers function scope and closures activation objects (although the book goes into more detail in Chapter 16).

In my original post on the new Flash Player 10 Vector class, I did a simple example that showed Vectors being slightly faster than Array when just populating and looping through collections. Below is another example that shows a more significant performance increase when using Vectors. In this example, I populate an Array and Vector with 5 million random numbers, and then loop through them and average all of the numbers.

If you read my blog regularly (or just today) you should have noticed that I have been playing around with some Pixel Bender filters and ActionScript / Flex (all inspired by Lee Brimelow`s video screencast on creating and using Pixel Bender filters in Flash Player 10.) Previously, I posted some code showing how to embed a custom Pixel Bender filter within a SWF and then apply the filter to an image.

One of the new features in Flash Player 10 are new ActionScript FileReference APIs that allow Flash content to directly read and write data to the user’s system. Prior to Flash Player 10, in order to read or write a file to the user’s system, Flash content would first have to bounce it off of a server, and then load it back to the users system before it could be accessed.

One of the new ActionScript features included in the Flash Player 10 Public Beta is the inclusion of a Vector class. Essentially, the Vector class is a typed Array, and in addition to ensuring your collection is type safe, can also provide (sometimes significant) performance improvements over using an Array. Using the Vector class is pretty simple, and very similar to using an Array. In fact, the Vector class contains all of the same methods as the Array class.

Since the first leg of the European on AIR Tour wrapped up, I have had some time to take some time and research / play around with some new technologies. In particular, I have been looking into the HTML 5 draft spec, as well as some of the work that Google has been doing with Google Gears. One thing I have been watching closely around the HTML 5 draft is the implementation of the VIDEO element / tag.

One of the ActionScript libraries that I use most is the as3syndicationlib. This is an opensource library originally developed by Christian Cantrell, and open sourced by Adobe. The library provides code for parsing RSS 1.0, RSS 2.0 and ATOM data feeds. It also provides a generic interface for parsing feeds when you do not know the format of the feeds. Below is a simple example of how to use the library to parse an RSS 2.

One of the things that you might need to do when building your application is detecting whether your application has run before. This can be useful if you need to initialize settings, or perhaps prompt the user with some information. Below is a simple example that shows how to detect whether the application has run before. Basically, it checks for the existence of a file. If it doesn’t exist, then the app hasn’t run before, if it does exist, then it means that app has run.