Scrolling with keys

[Dar Scott]

On Monday, June 23, 2003, at 10:55 AM, Ken Norris wrote:

> So, how would I scroll an image with a keypress while it's down, then 
> stop
> on keyup.

Something like this might get you started:

local sendID = ""
local toTheRight = "false"
local toTheLeft  = "false"
constant rightArrow = 65363
constant leftArrow = 65361
constant stepSize = 4
constant stepPeriod = 0.2

on rawKeyDown keyCode
   if keyCode is rightArrow then put true into toTheRight
   if keyCode is leftArrow  then put true into toTheLeft
   updateMoving
end rawKeyDown

on rawKeyUp keyCode
   if keyCode is rightArrow then put false into toTheRight
   if keyCode is leftArrow  then put false into toTheLeft
   updateMoving
end rawKeyUp

on updateMoving
   if (toTheRight or toTheLeft) then
     if sendID is empty then
       moveStep
     end if
   else
     cancel sendID
     put empty into sendID
   end if
end updateMoving

on moveStep
   if toTheRight then
     if the right of image "My Image" < 320 then
       move image "My Image" rel (stepSize,0) in stepPeriod seconds 
without waiting
     end if
   else
     if the left of image "My Image" > 5 then
       move image "My Image" rel ((-stepSize),0) in stepPeriod seconds 
without waiting
     end if
   end if
   send moveStep to me in stepPeriod seconds
   put the result into sendID
end moveStep


Dar Scott