Developing Flash Applications with Flex Builder
I miss programming. For years, I developed software for large companies, first using Lotus Notes and then Macromedia Flash. I have spent the past three years in a totally nonprogramming job, developing Web sites, writing whitepapers and otherwise doing nontechnical things. I like writing, but I miss programming. I wanted to get back into development, and as a Linux Journal writer, I wanted to use free software if possible. The thing is, my background is all in not only proprietary but also highly specialized software. I have never programmed in C or Java or Perl or any of the other popular general-purpose languages. I certainly could learn one, but I would prefer not to start from scratch with a whole new system at this stage of my career.
After Adobe bought Macromedia, it released the Flex SDK under the Mozilla Public License, so it now is possible to develop Flash applications using entirely free software. It also has released an alpha version of its Eclipse-based Flex Builder development environment for Linux. Flex Builder is released under a proprietary license.
Flex applications also can be defined using MXML, an XML dialect that is used to lay out the user interface and other aspects of the program, such as data bindings. Behaviors still are defined using ActionScript.
Flash applications generally run in the browser. They offer many of the advantages of AJAX or Silverlight applications, including a stateful client that can update specific items without reloading the entire page, and the Flash Player sandboxes applications in much the same way that a Java applet is restricted for security reasons.
Perhaps the two best-known AIR applications are the Pandora Internet radio player and TweetDeck, which streamlines the Twitter experience. Both work on Linux.
In this article, I demonstrate how to create a simple Flash application using Adobe Flex Builder on a Linux system. In a follow-up article, I'll move on to totally open-source development using Project Sprouts.
Flex is an Eclipse-based environment. In order to use it, you must have certain prerequisite software installed: Eclipse 3.3.x, Sun JRE 1.5 or newer and Mozilla Firefox 3.0.
Note that the system requirements refer specifically to Eclipse 3.3. If you use a higher version, installation will succeed, but Eclipse will fail to open code editors. I installed version 3.3.2 from eclipse.org (see Resources) in my $HOME directory. You can install 3.3 alongside 3.5 on the same computer, as long as you start version 3.3 to use Flex. Simply untar the download and place it anywhere in the filesystem. I put it in $HOME/eclipse.
I was able to use Flex Builder with Mozilla Firefox version 3.5, however, rather than the called-for 3.0 without problems. One Firefox tip: I use the NoScript plugin. At first, I thought the context-sensitive help in Flex Builder wasn't working, but it turns out that I had to allow scripts from 127.0.0.1:51296.
Also, note that you must install the Sun JRE. GCJ will not work with Flex.
To make debugging work, you must download and install the debugging version of the Flash Player (see Resources). Amusingly, when you try to run Adobe's installer on Ubuntu 9.10 (Karmic Koala), it complains because you don't have libc6 “higher” than 2.3. In fact, Karmic ships with version 2.10 (read as “2 dot 10”), which is higher than 2.3 in version-speak but not in normal numbering. I edited the script to remove the version check by commenting out these lines:
#GLIBCSTATUS=`check_glibc` #case $GLIBCSTATUS in # invalid-glibc) # exit_glibc # ;; #esac
With those edits, the install completed without further problems.
You can download the Flex alpha from Adobe's Web site (see Resources), and you need to create a free account first. Once you have it downloaded, do a chmod u+x on the file and run the downloaded file to install. Flex Builder uses a Windows-style graphical wizard installer. I installed into /home/carlf/AdobeFlexBuilderLinux, which meant I did not need to become superuser to complete the installation.
To use Flex Builder, simply start Eclipse. Being old-school, I did this by typing ./eclipse/eclipse & in a GNOME terminal (Figure 1).
The first time you run Eclipse after installing Flex Builder, you must create a new Workspace. Simply click File→Switch Workspace→Other and create a new folder.
Flex Builder for Linux, as an alpha, is missing several features present in the Windows and Mac versions:
Cold Fusion Data Services Wizard
Web Services Introspection
Depending on the type of project you are planning, these features may be either critical or unimportant.
Because this was my first experience with Eclipse, I took time to review the Eclipse tutorials before closing the Welcome screen. To switch from the default Java development environment to Flex, click Windows→Open Perspective→Other, and select Flex Development. Now, create a Flex project by clicking File→New→Flex Project. I chose to create a browser-based SWF file and named it “FirstProject”.
For this first simple application, I decided to create a simple Internet quiz that asks the user some questions, then supplies a “Webcomics IQ” score (I'm a big fan of Webcomics). This let me avoid having to worry about server database access on my first project. For this project, I need to use MXML to draw a simple form, which contains a question (text field) and four possible answers (radio buttons), along with a Next button. When the user clicks Next, the next question is displayed in the text field. After the last question, the score is displayed.
Because Flex Builder for Linux lacks a GUI painter (the Design View is absent), I created the components by typing MXML code into the editor. First, I write the text of the first question.
Until recently, IBM’s Power Platform was looked upon as being the system that hosted IBM’s flavor of UNIX and proprietary operating system called IBM i. These servers often are found in medium-size businesses running ERP, CRM and financials for on-premise customers. By enabling the Power platform to run the Linux OS, IBM now has positioned Power to be the platform of choice for those already running Linux that are facing scalability issues, especially customers looking at analytics, big data or cloud computing.
￼Running Linux on IBM’s Power hardware offers some obvious benefits, including improved processing speed and memory bandwidth, inherent security, and simpler deployment and management. But if you look beyond the impressive architecture, you’ll also find an open ecosystem that has given rise to a strong, innovative community, as well as an inventory of system and network management applications that really help leverage the benefits offered by running Linux on Power.Get the Guide
- Google's Abacus Project: It's All about Trust
- Seeing Red and Getting Sleep
- Download "Linux Management with Red Hat Satellite: Measuring Business Impact and ROI"
- Fancy Tricks for Changing Numeric Base
- Secure Desktops with Qubes: Introduction
- Working with Command Arguments
- Secure Desktops with Qubes: Installation
- CentOS 6.8 Released
- Linux Mint 18
- The Italian Army Switches to LibreOffice