Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. General and Desktop
  4. QTouchEvent, interaction lost
Qt 6.11 is out! See what's new in the release blog

QTouchEvent, interaction lost

Scheduled Pinned Locked Moved General and Desktop
5 Posts 2 Posters 1.7k Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • C Offline
    C Offline
    CClercq
    wrote on last edited by
    #1

    Dear all,

    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?

    Thanks.

    Charles.

    1 Reply Last reply
    0
    • T Offline
      T Offline
      tilsitt
      wrote on last edited by
      #2

      Hi,

      It would be easier to answer you with some demonstrating code.

      1 Reply Last reply
      0
      • C Offline
        C Offline
        CClercq
        wrote on last edited by
        #3

        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...

        1 Reply Last reply
        0
        • C Offline
          C Offline
          CClercq
          wrote on last edited by
          #4

          Lat news:

          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
          @QEvent::TouchBegin
          QEvent::TouchEnd@

          I also observe that sometimes their is no event received among:
          @QEvent::TouchBegin
          QEvent::TouchUpdate
          QEvent::TouchEnd
          QEvent::MouseButtonDblClick
          QEvent::MouseButtonPress
          QEvent::MouseButtonRelease
          QEvent::MouseMove
          QEvent::MouseTrackingChange@

          I continue to investigate, but if you have any clues...

          1 Reply Last reply
          0
          • C Offline
            C Offline
            CClercq
            wrote on last edited by
            #5

            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...

            1 Reply Last reply
            0

            • Login

            • Login or register to search.
            • First post
              Last post
            0
            • Categories
            • Recent
            • Tags
            • Popular
            • Users
            • Groups
            • Search
            • Get Qt Extensions
            • Unsolved