how to set the number of objects in stack

[irfan qasim]

hi guys,,

i m working on one appliction in which i am using different trucks for hearvesting purpose,
i am trying to set the number of trucks so that when the specified number are created then it must stop and display one window box to inform .
my code is given below please help me how to set the number trucks rather then repeat to the number of controls of this card.

global gSimulating

on mouseUp
put "java JRSocket 54322 10000" into tProcess
open process tProcess for neither
put ("localhost:54322") into tSocket
open socket tSocket
--If there is not a control "txttruck" then
if there is not a control "txttruck" then
answer "Please create a txtfield first!"
exit mouseUp
end if
write "Plant need trucks to collect items from field" & return to socket tSocket
write "plant : I need trucks to harvest 100 tons" & return to socket tSocket
write "Target is harvest" & return to socket tSocket
write field "txttruck" & return to socket tSocket
read from socket tSocket until return
put it into pResult
if pResult="movetruck"
then

if gSimulating is not "true"
then
put "true" into gSimulating
set the icon of me to 1038
--set the controls of this card to n
put field "txttruck" into f
if f>2*n
then
answer "stop process"
else
put n+1 into n and repeat until f>=1*2^n

repeat with x = 1 to the number of controls of this card
if the Kind of control x is "Truck" then
put true into sThereIsAtruck
if the Status of control x is not empty then send moveStopped to control x
if the Status of control x is empty then
wait 0.5 second
set the Status of control x to "Unloading"
set the DestinationID of control x to the ID of control "Plant 1"
move control x to the location of control "Plant 1" without waiting
end if
end if
end repeat
if sThereIsAtruck is not true
then
answer "You must have at least one Mobile Object to run a Simulation!"
put "false" into gSimulating
set the icon of me to 1040
exit mouseUp
end if
else
put "false" into gSimulating
set the icon of me to 1040
repeat with x = 1 to the number of controls of this card
if the Kind of control x is "Truck" then
stop moving control x
end if
end repeat
end if
send "upDateFieldNodeInfo" to group "Tree1"
if tSocket is among the lines of the openSockets then close socket tSocket
end if

end mouseUp