Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. Mobile and Embedded
  4. Qt Gui App on Rasppberry pi Touch Screen Problem
Forum Updated to NodeBB v4.3 + New Features

Qt Gui App on Rasppberry pi Touch Screen Problem

Scheduled Pinned Locked Moved Unsolved Mobile and Embedded
5 Posts 2 Posters 1.2k Views
  • 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.
  • Q Offline
    Q Offline
    qtross
    wrote on 4 Apr 2019, 07:28 last edited by
    #1

    I am working on a kiosk app on rasbian stretch with 10.1 inc HDMI screen. I installed qt-creator and required libraries on raspberry pi and copied my project file on it. I am able to run my app while I am on startx which causes my first touch to control only cursor. After my cursor is pointed on pushbutton, then I need to push one more time to push my pushbutton. The problem in there is I would like to use pushbuttons when my first touch is pressed on screen.

    Solutiouns I have tried:

    I thought using my app without startx I mean without no rasbian gui. When I run my app from with terminal booted rasbian, that delivers another problem;
    
        qxcbconnection could not connect to display
    

    I searched on google this and tried possible solution:

    export display=:0 or export display=:0.0

    which doesn't solve problem but change this;

    qxcbconnection could not connect to display:0 or :0.0
    
    I have tried also running my app with using ssh;
    

    ssh -X root@raspberry ./project1 (while my current directory is build folder)

    It did not solve either. Thanks for any suggestion.

    J 1 Reply Last reply 4 Apr 2019, 08:23
    0
    • Q qtross
      4 Apr 2019, 07:28

      I am working on a kiosk app on rasbian stretch with 10.1 inc HDMI screen. I installed qt-creator and required libraries on raspberry pi and copied my project file on it. I am able to run my app while I am on startx which causes my first touch to control only cursor. After my cursor is pointed on pushbutton, then I need to push one more time to push my pushbutton. The problem in there is I would like to use pushbuttons when my first touch is pressed on screen.

      Solutiouns I have tried:

      I thought using my app without startx I mean without no rasbian gui. When I run my app from with terminal booted rasbian, that delivers another problem;
      
          qxcbconnection could not connect to display
      

      I searched on google this and tried possible solution:

      export display=:0 or export display=:0.0

      which doesn't solve problem but change this;

      qxcbconnection could not connect to display:0 or :0.0
      
      I have tried also running my app with using ssh;
      

      ssh -X root@raspberry ./project1 (while my current directory is build folder)

      It did not solve either. Thanks for any suggestion.

      J Offline
      J Offline
      jsulm
      Lifetime Qt Champion
      wrote on 4 Apr 2019, 08:23 last edited by jsulm 4 Apr 2019, 08:24
      #2

      @qtross said in Qt Gui App on Rasppberry pi Touch Screen Problem:

      qxcbconnection could not connect to display

      Without XServer running (startx) you can't use X11 applications. So, this is not a solution. You should rather find out what is wrong with the touch display.
      Does the touchscreen work properly with other applications?

      https://forum.qt.io/topic/113070/qt-code-of-conduct

      1 Reply Last reply
      1
      • Q Offline
        Q Offline
        qtross
        wrote on 4 Apr 2019, 10:51 last edited by
        #3

        @jsulm Thank you for the reply.
        Here is the model of my touch display. I am trying to find out what the problem is.
        https://www.waveshare.com/10.1inch-hdmi-lcd-with-case.htm

        I tried with another kiosk project of qt which I found on internet, it works same as mine, needs to be touched two times for pressing the button. However, the person who shared this project can use this with pressing one touch. So as you say, I have problem with the touch display or I am missing something that I need to fix on rasbian.

        Thanks

        J 1 Reply Last reply 4 Apr 2019, 11:50
        0
        • Q qtross
          4 Apr 2019, 10:51

          @jsulm Thank you for the reply.
          Here is the model of my touch display. I am trying to find out what the problem is.
          https://www.waveshare.com/10.1inch-hdmi-lcd-with-case.htm

          I tried with another kiosk project of qt which I found on internet, it works same as mine, needs to be touched two times for pressing the button. However, the person who shared this project can use this with pressing one touch. So as you say, I have problem with the touch display or I am missing something that I need to fix on rasbian.

          Thanks

          J Offline
          J Offline
          jsulm
          Lifetime Qt Champion
          wrote on 4 Apr 2019, 11:50 last edited by
          #4

          @qtross Did you try to use this touchscreen with the default Raspbian desktop environment? Does it behave same way?

          https://forum.qt.io/topic/113070/qt-code-of-conduct

          Q 1 Reply Last reply 4 Apr 2019, 12:32
          0
          • J jsulm
            4 Apr 2019, 11:50

            @qtross Did you try to use this touchscreen with the default Raspbian desktop environment? Does it behave same way?

            Q Offline
            Q Offline
            qtross
            wrote on 4 Apr 2019, 12:32 last edited by
            #5

            @jsulm Yes, in desktop blank area when cursor is someplace and when i press another blank place, it behaves like I am selecting these between area. In mouse act, I need to keep pressing left click of the mouse and pull the mouse to make this behave.

            1 Reply Last reply
            0

            1/5

            4 Apr 2019, 07:28

            • Login

            • Login or register to search.
            1 out of 5
            • First post
              1/5
              Last post
            0
            • Categories
            • Recent
            • Tags
            • Popular
            • Users
            • Groups
            • Search
            • Get Qt Extensions
            • Unsolved