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USING FLASH CS4 PROFESSIONAL
Best practices
When to use behaviors
The main difference between a FLA file with behaviors and a FLA file without behaviors is the workflow you must use
for editing the project. If you use behaviors, you must select each instance on the Stage, or select the Stage, and open
the Actions or Behaviors panel to make modifications. If you write your own ActionScript and put all your code on
the main Timeline, you only have to make your changes on the Timeline.
If you have a FLA file with symbols, you can select one of the instances on the Stage, and use the Add menu on the
Behaviors panel to add a behavior to that instance. The behavior you select automatically adds code that attaches to
the instance, using “object code” such as the
on()
handler. You can also select a frame on a timeline, and add different
behaviors to a frame using the Behaviors panel.
Decide how to structure your FLA file. Examine how and where to use behaviors and ActionScript in your FLA file.
Consider the following questions:
•
What code do the behaviors contain?
•
Do you have to modify the behavior code? If so, by how much? To modify the behavior code to any extent, do not
use behaviors. You usually cannot edit behaviors by using the Behaviors panel if you make modifications to the
ActionScript. To significantly edit the behaviors in the Actions panel, it is usually easier to write all of the
ActionScript yourself in a centralized location.
•
What other ActionScript do you need, and does other ActionScript have to interact with the behavior code?
Debugging and modifications are easier to make from a central location. For example, if code on a timeline interacts
with behaviors placed on objects, avoid behaviors.
•
How many behaviors do you have to use, and where do you plan to put them in the FLA file? If your behaviors are
all placed on a timeline, they might work well in your document. Or, your workflow might not be affected if you
use only a small number of behaviors. However, if you use many behaviors on a lot of object instances, writing your
own code on the Timeline or in external ActionScript files might be more efficient.
Remember, ActionScript 3.0 does not support behaviors.
Using behaviors consistently
Use behaviors consistently throughout a document when they are your main or only source of ActionScript. Use
behaviors when you have little or no additional code in the FLA file, or have a consistent system in place for managing
the behaviors that you use.
If you add ActionScript to a FLA file, put code in the same locations where behaviors are added, and document how
and where you add code.
For example, if you place code on instances on the Stage (object code), on the main Timeline (frame scripts), and also
in external AS files, examine your file structure. Your project will be difficult to manage if you have code in all of these
places. However, if you logically use behaviors and structure your code to work in a particular way surrounding those
behaviors (place everything on object instances), at least your workflow is consistent. The document will be easier to
modify later.
Sharing files that use behaviors
If you plan to share your FLA file with other users and you use ActionScript placed on or inside objects (such as movie
clips), it can be difficult for those users to find your code’s location, even when they use the Movie Explorer to search
through the document.
Document the use of behaviors if you are working with a complex document. Depending on the size of the application,
create a flow chart, list, or use good documentation comments in a central location on the main Timeline.
Updated 5 March 2009
