[SOLVED] QTouchEvent contains only 2 TouchPoints on Windows7?
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Hi all,
I'm using Qt 4.8.5 on Windows 7 with VC2010. My application uses touch events for a pinch function. For pinching I need only two touch points - it works.
But know I want to add some functions if user touches the screen more than twice.
for example user touches with 3 finger to screen I will maximize the application window. But following is never called:@::event(QEvent* e)
{
...
QListQTouchEvent::TouchPoint touchPoints = event->touchPoints();
if (touchPoints.count() == 3)
{
qDebug("yeahh, 3 points touched!");
}
}@Does anybody has an idea? Please don't say it's part of the platform. Is it possible that Qt doesn't fully implement the platform touch API?
THX
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BTW the fingerprints example works also only with 2 touches. When a third is touched absolutly nothing happens.
I would say "Qt supports multitouch events" is limited to 2 touches :-(
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i would rather say that your touch screen only supports 2 touch points.
Please check the specs of your hardware -
[quote author="raven-worx" date="1375365731"]i would rather say that your touch screen only supports 2 touch points.
Please check the specs of your hardware[/quote]Do you have some experience with other hardware on Windows 7?
Are you able to catch more than 2 touches on a Windows 7 system?I want to make sure that it's a hardware problem and not in Qt.
I'm using a iiyama ProLite T2250MTS. Currently I'm looking for a test program which catches the touches/gestures.
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as i said: your touchscreen only supports 2 touch-points
http://www.iiyama.com/gl_en/products/prolite-t2250mts-1/[quote]
Touchtechnology : optical, multitouch (2 compatible touch points), activated by finger or stylus
[/quote]meaning it sends only two touchpoints to the OS driver which forwards it as windows events to your Qt application.
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Qt easily accepts multiple touch points, for example swipe gesture requires 3 touch points by default.
check "this":http://qt-project.org/doc/qt-4.8/qswipegesture.html#note-219 and "this":http://qt.gitorious.org/qt/qt/blobs/4c400ec8e397b4da9898f96c50a702eaa362293d/src/gui/kernel/qstandardgestures.cpp
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Thanks a lot. I found the same article. Also that Windows 7 is poor supporting more than 2 fingers :-(
I will try to port Qt's fingerprint example to my Nexus7. Maybe I have luck and more than 2 finger prints output.
Then I have the evidence that Qt works fine.
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again...this has nothing todo with windows 7 supporting multi-touch points poorly!
It's just your hardware which only forwards max 2 touch-points to the operating system. -
[quote author="raven-worx" date="1375694273"]again...this has nothing todo with windows 7 supporting multi-touch points poorly!
It's just your hardware which only forwards max 2 touch-points to the operating system.[/quote]I completely agree, its a hardware problem nothing to do with windows 7 or Qt.
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ok, only hardware problem, I understand. Then it's time to inform my boss to buy an other screen which supports more than 2 points.
Do you have any experience with screens supporting more than 2 points?
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Exactly, it a hardware problem! I tried the fingerprints example on a Windows 8 tablet which supports 5-touch points and it works.
The "system control" tells you how many touch points are supported.