Datasheet

One drawback that application developers encounter with Flash is that the primary source docu-
ment used in Flash, the .fla file format, is binary. As a result, it doesn’t work well with the source
control systems that application developers commonly use to manage their development projects,
because you can’t easily “diff,” or discover differences between, different versions of a binary file.
Developing in Flex
Developers who use Flex to build their applications commonly have a background in some other
programming language. Documents can be created and made useful in Flash without any program-
ming, but a Flex application is almost entirely code-based. Animations are handled entirely
through ActionScript, because Flex doesn’t have a timeline as part of its development toolkit.
Flex also has superior tools for handling large-scale applications that have dozens or hundreds of
views, or screens. Although Flash CS3 has a screen document feature, this feature hasn’t received
the development attention from Adobe that would make it a compelling architectural choice for
these “enterprise” applications.
Finally, Flex applications are built in source code, which is stored in text files. These text files are
easy to manage in source-code control applications such as CVS and Subversion. As a result, multi-
developer teams who are dependent on these management tools find Flex development to be a nat-
ural fit to the way they already work.
The Flex Builder 3 design view feature has become more friendly and useful to graphic designers
than in previous versions, but it isn’t always intuitive to a designer who’s used to “real” graphic
design tools like Adobe’s own Photoshop, Illustrator, and Fireworks.
Table 1.1 describes some of the core differences between Flex and Flash development.
TABLE 1.1
Differences between Flex and Flash Development
Task Flex Flash
Animation Flex uses ActionScript classes called The Flash timeline allows animation
Effects to define and play animations. frame-by-frame or tweening, and also
There is no timeline. supports programmatic animation with
ActionScript.
Working with data Flex has multiple tools for working Flash can communicate with the same
with data and application servers, RPC sources as Flex, but its programming
including the RPC components tools aren’t as intuitive or robust.
(HTTPService, WebService, and
RemoteObject). It is also a natural fit
for use with LiveCycle Data Services.
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Flex Fundamentals
Part I
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