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MouseWheel Scroll Direction

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Jim

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Jul 21, 2008, 8:58:19 AM7/21/08
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Once in a while I get a comment that my application scrolls windows in
the opposite direction that the rest of the applications on a
particular computer do. Any thoughts as to why this may be?

I am using D7.

Thanks,
Jim
--
www.mustangpeak.net

Peter Below (TeamB)

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Jul 21, 2008, 1:43:50 PM7/21/08
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Jim wrote:

>
> Once in a while I get a comment that my application scrolls windows in
> the opposite direction that the rest of the applications on a
> particular computer do. Any thoughts as to why this may be?

Do you handle OnMousewheel events in your code somewhere? And which
controls are affected by this problem? For most controls the VCL just
leaves the mouse wheel handling to the OS, you know...

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Jim

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Jul 21, 2008, 9:19:54 PM7/21/08
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Peter Below (TeamB) wrote:

> Jim wrote:
>
> >
> > Once in a while I get a comment that my application scrolls windows
> > in the opposite direction that the rest of the applications on a
> > particular computer do. Any thoughts as to why this may be?
>
> Do you handle OnMousewheel events in your code somewhere? And which
> controls are affected by this problem? For most controls the VCL just
> leaves the mouse wheel handling to the OS, you know...

Yes, as most of the controls are either mine (EasyListview,
VirtualShellTools) or Mike Lischke' (VirtualTreeview)

Jim
--
www.mustangpeak.net

Peter Below (TeamB)

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Jul 22, 2008, 1:27:33 PM7/22/08
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Jim wrote:

Then examine how you interpret the delta value of the message. It's
dead easy to scroll in the wrong direction if you don't read the MS
docs very carefully, since its somewhat unintuitive, due to the fact
that the Windows standard coordinate system is upside down from a
normal cartesian one.

Jim

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Jul 22, 2008, 9:35:20 PM7/22/08
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> Then examine how you interpret the delta value of the message. It's
> dead easy to scroll in the wrong direction if you don't read the MS
> docs very carefully, since its somewhat unintuitive, due to the fact
> that the Windows standard coordinate system is upside down from a
> normal cartesian one.

Understood but why does it seem to work "correct" on my and many others
system for years and I only get this once it a blue moon (two that I
can recall in 4+ years)

Jim
--
www.mustangpeak.net

Peter Below (TeamB)

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Jul 23, 2008, 2:07:37 PM7/23/08
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Jim wrote:

In this case I would suspect buggy mouse drivers on the users system
and not your program code.

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