User Guide

60 Chapter 3: Writing Scripts in Director
In addition to checking the properties that you assign, you can check whether a child object
contains a specific handler or find out which parent script an object came from. This is useful
when you have objects that come from parent scripts that are similar but that have subtle
differences.
For example, you may want to create a scenario in which one of several parent scripts might be
used to create a child object. You can then determine which parent script a particular child object
came from by using the
script() function, which returns the name of an object’s parent script.
The following statements check whether the object
car1 was created from the parent script
named
Car:
-- Lingo syntax
if car1.script = script("Car") then
_sound.beep()
end if
You can also get a list of the handlers in a child object by using the handlers() method, or check
whether a particular handler exists in a child object by using the
handler() method.
The following statement places a list of the handlers in the child object
car1 into the variable
myHandlerList:
-- Lingo syntax
myHandlerList = car1.handlers()
The resulting list would look something like this:
[#start, #accelerate, #stop]
The following statements use the handler() method to check whether the handler on
accelerate
exists in the child object car1:
-- Lingo syntax
if car1.handler(#accelerate) then
put("The child object car1 contains the handler named on accelerate.")
end if
Removing a child object
You can remove a child object from a movie by setting all variables that contain a reference to the
child object to another value. If the child object has been assigned to a list, such as
actorList,
you must also remove the child object from the list.
To remove a child object and the variables that refer to it:
• Set each variable to VOID.
Director deletes the child object when there are no more references to it. In the following
example,
ball1 contains the only reference to a specific child object, and it is set to VOID to delete
the object from memory.
-- Lingo syntax
ball1 = VOID
To remove an object from actorList:
• Use the delete() method to delete the item from the list.