Lingo Dictionary > A-C > call

 

call

Syntax

call #handlerName, script, {args...}
call (#handlerName, scriptInstance, {args...})

Description

Command; sends a message that invokes a handler in specified scripts where handlerName is the name of the handler to be activated, script references the script or a list of scripts, and args are any optional parameters to be passed to the handler.

If script is a single script instance, an error alert occurs if the handler is not defined in the script's ancestor script.

If script is a list of script instances, the message is sent to each item in the list in turn; if the handler is not defined in the ancestor script, no alert is generated.

The call command can use a variable as the name of the handler. Messages passed using call are not passed to other scripts attached to the sprite, cast member scripts, frame scripts, or movie scripts.

Example

This handler sends the message bumpCounter to the first behavior script attached to sprite 1:

on mouseDown me
	-- get the reference to the first behavior of sprite 1
	set xref = getAt (the scriptInstanceList of sprite 1,1)
	-- run the bumpCounter handler in the referenced script, 
	-- with a parameter
	call (#bumpCounter, xref, 2)
end

Example

This example shows how a call statement can call handlers in a behavior or parent script and its ancestor.

This is the parent script:

-- script Man
property ancestor
on new me
	set ancestor = new(script "Animal", 2)
	return me
end
on run me, newTool
	put "Man running with "&the legCount of me&" legs"
end

This is the ancestor script:

-- script Animal
property legCount
on new me, newLegCount
	set legCount = newLegCount
	return me
end
on run me
	put "Animal running with "& legCount &" legs"
end
on walk me
	put "Animal walking with "& legCount &" legs"
end

The following statements use the parent script and ancestor script.

This statement creates an instance of the parent script:

set m = new(script "man")

This statement makes the man walk:

call #walk, m
-- "Animal walking with 2 legs"

This statement makes the man run:

set msg = #run
call msg, m
-- "Man running with 2 legs and rock"

This statement creates a second instance of the parent script:

set m2 = new(script "man")

This statement sends a message to both instances of the parent script:

call msg, [m, m2]
-- "Man running with 2 legs "
-- "Man running with 2 legs "