Macromedia dreamweaver 8-extending dreamweaver User Manual

A simple behavior example

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Inserting multiple functions in the user’s file

Actions can insert multiple functions—the main behavior function plus any number of helper 
functions—into the 

HEAD

 section. Two or more behaviors can even share helper functions as 

long as the function definition is exactly the same in each Action file. One way of ensuring 
that shared functions are identical is to store each helper function in an external JavaScript file 
and insert it into the appropriate Action files using 

<SCRIPT SRC="externalFile.js">

.

When the user deletes a behavior, Dreamweaver attempts to remove any unused helper 
functions that are associated with the behavior. If other behaviors are using a helper function, 
it is not deleted. Because the algorithm for deleting helper functions errs on the side of 
caution, Dreamweaver might occasionally leave an unused function in the user’s document.

What to do when an action requires a return value

Sometimes an event handler must have a return value (for example, 

onMouseOver="window.status='This is a link'; return true"

). But if Dreamweaver 

inserts the 

"return behaviorName(args)"

 action into the event handler, behaviors later in 

the list are skipped.

To get around this limitation, set the 

document.MM_returnValue

 variable to the desired 

return value within the string that the 

behaviorFunction()

 function returns. This setting 

causes Dreamweaver to insert 

return document.MM_returnValue

 at the end of the list of 

actions in the event handler. For an example that uses the 

MM_returnValue 

variable, see the 

Validate Form.js file in the Configuration/Behaviors/Actions folder within the Dreamweaver 
application folder.

A simple behavior example

To understand how behaviors work and how you can create one, it’s helpful to look at an 
example. The Configuration/Behaviors/Actions folder inside the Dreamweaver application 
folder contains examples; however, many are very complex. This example is simpler so that 
you can learn about creating behaviors. Start with the simple Action file Call JavaScript.htm 
(along with its counterpart, Call JavaScript.js, which contains all the JavaScript functions).

To create the behavior, you perform the following steps:

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