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Rotary encoder problem

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

    Hence my question: how is that method called ? Do you have a signal connected to it ?

    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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    • A Offline
      A Offline
      allanbic
      wrote on last edited by
      #5

      Yes, I have some knobs connected to the application, which increment or decrement with the rotation. It's a lung ventilator project, each knob has a function, such as: tidal volume, frequency, flow, peep, limit pressure... when I click on the screen, I can control these knobs through the left and right keys, however I would like to use an encoder for this and also keep the keys working!

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

        That is clear and understood. What you are not answering is: how is onKeyPress called ?
        What is the flow between your encoder back to your GUI ?

        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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        • A Offline
          A Offline
          allanbic
          wrote on last edited by
          #7

          connect(parent, SIGNAL(KeyPress(int)),this,SLOT(onKeyPress(int)));
          Is it?

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

            Then how is KeyPress emitted ?

            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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            • A Offline
              A Offline
              allanbic
              wrote on last edited by
              #9

              By KeyPressEvent(QKeyEvent * e).

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              • M Offline
                M Offline
                mchinand
                wrote on last edited by
                #10

                What is the output from the rotary encoder that your application can respond to? Does it appear as a keyboard to the OS?

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                • A Offline
                  A Offline
                  Anonymous_Banned275
                  wrote on last edited by
                  #11

                  Doesn't rotary encoder outputs min of two "digits" ? Then you compare previous to current output to determine direction of rotation and from that derive "up or down " value to be added / deleted .

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                  • A Offline
                    A Offline
                    allanbic
                    wrote on last edited by allanbic
                    #12

                    @mchinand Hi, how are you? Have a great day. No, It is found as rotary encoder even by the operating system, but the qt app was configured to detect only the keyboard keys, and I would like to make the keyboard and the encoder work simultaneously. But I'm not sure how to make the encoder work in the qt application.

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                    • M mchinand

                      What is the output from the rotary encoder that your application can respond to? Does it appear as a keyboard to the OS?

                      A Offline
                      A Offline
                      allanbic
                      wrote on last edited by allanbic
                      #13

                      @AnneRanch , Thanks for your answer! The problem is that I don't know how to add the encoder functions in my application. It is already working on the OS, but I don't know how to call it in the app...

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

                        Can you explain how it is "working with the OS" ?
                        How would you retrieve the data ?

                        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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