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Posted: **Thu Feb 26, 2009 10:15 pm**

Hi all,

I want a progress bar (0 to 100) to tick down to 0 in about 2 seconds. At a thumbPos of 0, a buzz will sound indicating an error. The way to stop the progress bar is to respond to the card with a 'y' or 'n' keypress. I've been trying this for over a day now to no avail. Source code is below. Any help would be appreciated. Thanks!

on openCard
global thisKey
set the beeppitch to 60
put the thumbposition of scrollbar "progress" into newThumbPosition
put the ticks into startTicks
repeat until thisKey = 'n' or thisKey = 'y'
--put (the ticks - startTicks) into timer
--if timer mod 500 = 0 then
put the thumbposition of scrollbar "progress" into newThumbPosition
put newThumbPosition - 1 into newThumbPosition
if newThumbPosition < 0 then put 0 into newThumbPosition
set the thumbposition of scrollbar "progress" to newThumbPosition
--end if --timer
end repeat
if newThumbPosition = 0 then
put true into tooLate
-- repeat for 1 second --until thisKey = 'y' or thisKey = 'n'
-- beep
-- end repeat
end if --0
end openCard

Posted: **Thu Feb 26, 2009 11:31 pm**

You don't seem to have a test in the code for a key being down, I'm not sure where you're setting the value of "thisKey"

I'd tackle this by using a "send in time" approach rather than a loop. Repeat loops are blocking structures and it can sometimes be difficult to get the keyboard to be read in between the iterations of the loop.

Try something like this:

In the scrollbar itself, put this code

Code: Select all

global gFlag

on cmdElapseTimer
   local tTimer
   put the thumbPosition of me into tTimer
   if gFlag is true and tTimer > 0 then
      subtract 2.5 from tTimer
      set the thumbPosition of me to tTimer
      send "cmdElapseTimer" to me in 50 milliseconds
   else
      beep
   end if
end cmdElapseTimer

In the card script, put:

Code: Select all

global gFlag

on openCard
   put true into gFlag
   set the thumbPosition of scrollbar "progress" to 100
   send cmdElapseTimer to scrollbar "progress"
end openCard

on rawKeyDown theKey
   put not (theKey is in "121,110,89,78") into gFlag
   pass rawKeyDown
end rawKeyDown

The timing isn't perfectly accurate to the millisecond, it takes about 2025 to 2030 milliseconds to run on my laptop.

On the card, the rawKeyDown codes 121, 110, 89, and 78 are the values returned by "y" and "n" with and without a Caps key held down. If any of those keys are down, then the global variable gFlag will be set to false.

In the scrollbar handler, the next iteration of the cmdElapseTimer handler will only be "sent" if the gFlag is true, and so your loop will be stopped, as it will if the progress bar reaches the end limit.

HTH

Posted: **Sun Mar 01, 2009 4:40 am**

Thanks HTH!

That comes out beautifully. This forum makes Revolution my favorite language hands down.

Josh

Posted: **Sun Mar 01, 2009 6:01 pm**

Glad it was useful. HTH is (blatantly stolen from Jan, hope he doesn't mind me using it in signoff) short for "Hope That Helps" though!

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