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QTouchEvent, interaction lost
I have a problem with the touch event on my tablet.
I developed a GUI, with buttons and an interactive "map" which consist of a QGraphicsScene with a QGraphicsPixMap and interactives zones inheriting from QGraphicsRectItem to overload mouseEvent().
The problem is that time-randomly I lose the "touch interaction" with the buttons and the interactive map, that is to say, that time-randomly the touches are not processed anymore. To get back the interaction I have to switch to another program (e.g. notepad, paint or what ever) and switch back to my program...
The thing is that I never lose the interaction using a mouse...
Could the problem come from a "full" stack?
tilsitt last edited by
It would be easier to answer you with some demonstrating code.
It is complicated to post example code as I do not know where the problem is in the whole project.
I mean, giving code would target a zone in the project where possibly the bug could lie, zone that I am not able to determine.
My question should have been: Does someone already observe a problem of interaction with an interface using touches but not using a mouse?
May be it come from my device, but it is strange as, when I loose the interaction, if I "touch" a button it becomes gray but nothing append.
I don't understand how it changes from both touches and mouse interaction work to only mouse interaction works...
I have implemented an event manager using eventFilter(...)
I can observe that the events received when used on the tablet with the touch screen are
I also observe that sometimes their is no event received among:
I continue to investigate, but if you have any clues...
Printing the type of event received I observe that sometimes instead of the couple QEvent::TouchBegin / QEvent::TouchEnd I receive some QEvent::HoverMove.
It is totally random, and if I click another button and come back to the previous I receive the right events...