3.2 The default application container - flex 3 and flex 4  (Page 3/12)

ActionScript is an issue for my XML students

While earlier versions of ActionScript may have been simple and easy to learn, ActionScript 3 is a fully object-oriented programming language with acomplexity level on par with C++.

Students in my XML class aren't required to have any programming knowledge, and aren't expected to have the prerequisite knowledge that would qualify them tolearn ActionScript 3 while learning XML at the same time. Therefore, the early lessons in this series concentrate on the use of mxml forlayout and control and forego any requirement to understand ActionScript 3. As I mentioned earlier, I teach object-oriented programming using ActionScript in adifferent course.

Viewing tip

I recommend that you open another copy of this document in a separate browser window and use the following links to easily find and view the figures andlistings while you are reading about them.

Figures

• Figure 1 . Flash Player output for a new Flex project.
• Figure 2 . Browser output for a new Flex project.
• Figure 3 . Application window background for alpha values of 0.0, 0.33, 0.66, and 1.0.
• Figure 4 . Gradient output for narrow ratio zone.
• Figure 5 . Flash window for Flex 4 project named AppBackground04.

Listings

• Listing 1 . Skeleton mxml code for a new Flex 3 project.
• Listing 2 . Flex 3 application named AppBackground01.
• Listing 3 . Skeleton mxml code for a new Flex 4 project.
• Listing 4 . Flex 4 application named AppBackground03.

Supplemental material

I recommend that you also study the other lessons in my extensive collection of online programming tutorials. You will find a consolidated index at www.DickBaldwin.com .

General background information

Download Flex

I have provided download links in Resources for both the free open source Flex SDKs and Flash Builder 4.

Flash Builder 4 includes the SDKs for both Flex 3 and Flex 4 along with an IDE that is useful for creating Flex applications. Both the raw SDK downloads and the Flash Builder 4 download includes a debug version of the AdobeFlash Player.

Install the Flex SDK

Installation of the free open source Flex SDKs is a little complicated (but I will explain how to do it in a future lesson) . I have provided a link in Resources for Installation and Release Notes.

Installation of Flash Builder 4 is straightforward, at least that is true for Windows. The download is an exe file. Just execute thedownloaded file and follow the installation instructions.

Getting started with the free SDKs

If you are using the free stand-alone SDKs, I will provide instructions for getting started creating applications with them in a future lesson. Thoseversions include a command-line compiler. You will need to create your mxml files using a text editor and compile them using the command-linecompiler.

Getting started with Flash Builder 4

If you are using Flash Builder 4, I have provided several links in Resources that will help you get started using the IDE. Perhaps the quickest way to get started is to view some of the videos at thelink titled Flex in a Week video training .