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Keyboard issues

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  • SGaistS Offline
    SGaistS Offline
    SGaist
    Lifetime Qt Champion
    wrote on last edited by
    #2

    Hi,

    eglfs is only handles the graphic part, you'll need to use e.g. the evdev plugin for your keyboard. More about this "here":http://doc.qt.io/qt-5/embedded-linux.html

    Interested in AI ? www.idiap.ch
    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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    • ? Offline
      ? Offline
      A Former User
      wrote on last edited by
      #3

      Hi,
      I've already read that document but still I cannot get it works.

      I export QT_QPA_EVDEV_KEYBOARD_PARAMETERS='grab=1', then I create my CoreApp class upon QCoreApplication. Here I reimplement the virtual bool event(QEvent *e).

      But no events are generated while pressing keys on the keyboard.

      Surely I'm missing something!

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      • SGaistS Offline
        SGaistS Offline
        SGaist
        Lifetime Qt Champion
        wrote on last edited by
        #4

        Did you specify the exact device to use as a keyboard ?

        Interested in AI ? www.idiap.ch
        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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        • ? Offline
          ? Offline
          A Former User
          wrote on last edited by
          #5

          I think is not necessary because there is only one input device: the keyboard itself.

          Anyway I tried to set that env var to '/dev/input/input0;grab=1' with no chance.

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          • SGaistS Offline
            SGaistS Offline
            SGaist
            Lifetime Qt Champion
            wrote on last edited by
            #6

            Did you check whether you have the rights to access that device ?

            Interested in AI ? www.idiap.ch
            Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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            • ? Offline
              ? Offline
              A Former User
              wrote on last edited by
              #7

              Yes I did. Currently, I'm running the application as root to avoid any problem related to the rights.

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              • SGaistS Offline
                SGaistS Offline
                SGaist
                Lifetime Qt Champion
                wrote on last edited by
                #8

                Then call your application with QT_DEBUG_PLUGINS=1 set, you'll see if there's something happening with the plugins.

                Interested in AI ? www.idiap.ch
                Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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                • ? Offline
                  ? Offline
                  A Former User
                  wrote on last edited by
                  #9

                  Setting QT_DEBUG_PLUGINS=1 leads to no warnings nor messages. The pressed keys are still sent to the console.

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                  • SGaistS Offline
                    SGaistS Offline
                    SGaist
                    Lifetime Qt Champion
                    wrote on last edited by
                    #10

                    Can you show your configuration and the command used to launch your application ?

                    Interested in AI ? www.idiap.ch
                    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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                    • ? Offline
                      ? Offline
                      A Former User
                      wrote on last edited by
                      #11

                      It's a Raspberry Pi Model B+ running a linux buildroot o.s.:

                      @

                      uname -a

                      Linux rpi 3.12.26 #1 PREEMPT Thu Oct 2 20:45:27 CEST 2014 armv6l GNU/Linux
                      @

                      Here the command I use to launch my application:

                      @
                      ./myapp
                      @

                      I also tried:

                      @
                      ./myapp < /dev/tty1
                      @

                      Even with the QT_QPA_EVDEV_KEYBOARD_PARAMETERS variable set, when I hit any key on the keyboard it will show the char on the console, instead of being grabbed by the application. I.e. no QCoreApplication::event() is emitted.

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                      • SGaistS Offline
                        SGaistS Offline
                        SGaist
                        Lifetime Qt Champion
                        wrote on last edited by
                        #12

                        What parameters did you set on QT_QPA_EVDEV_KEYBOARD_PARAMETERS ?

                        Interested in AI ? www.idiap.ch
                        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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                        • ? Offline
                          ? Offline
                          A Former User
                          wrote on last edited by
                          #13

                          As I said in a previous post I tried the following:

                          @
                          export QT_QPA_EVDEV_KEYBOARD_PARAMETERS=‘grab=1’
                          export QT_QPA_EVDEV_KEYBOARD_PARAMETERS=‘/dev/input/input0;grab=1’
                          @

                          Anyway the keyboard is the only input device available and also the only USB device connected.

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                          • SGaistS Offline
                            SGaistS Offline
                            SGaist
                            Lifetime Qt Champion
                            wrote on last edited by
                            #14

                            Are you running your application through ssh ?

                            Interested in AI ? www.idiap.ch
                            Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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                            • ? Offline
                              ? Offline
                              A Former User
                              wrote on last edited by
                              #15

                              The behavior is the same if either I launch the application through ssh or locally.

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                              • Halo_HaoH Offline
                                Halo_HaoH Offline
                                Halo_Hao
                                wrote on last edited by
                                #16

                                run:cat /proc/bus/input/devices

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