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Forum Update on Monday, May 27th 2025

UI doesnt refresh correctly

Scheduled Pinned Locked Moved Unsolved General and Desktop
qt5serial portuser interface
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  • D deleted286

    @mrjj said in UI doesnt refresh correctly:

    qDebug() << "-->"<< dizi[1] << dizi[2]<< dizi[3]<< dizi[4]<< dizi[5]<< dizi[6];

    I've checked, coming datas are true. Is there anything about threads? I have serial port and i have a gui. There may be something different about it

    mrjjM Offline
    mrjjM Offline
    mrjj
    Lifetime Qt Champion
    wrote on last edited by
    #10

    @suslucoder
    Hi
    Only if you added threads yourself. else it cant be the issue.

    So that data is right in top of on_joystick ?
    that you are very sure about ?

    Since we dont clear dizi between readyRead
    it will have old values.

    So waht excactly do you see ?
    first it work, then it stops. or it never works ?

    D 1 Reply Last reply
    0
    • mrjjM mrjj

      @suslucoder
      Hi
      Only if you added threads yourself. else it cant be the issue.

      So that data is right in top of on_joystick ?
      that you are very sure about ?

      Since we dont clear dizi between readyRead
      it will have old values.

      So waht excactly do you see ?
      first it work, then it stops. or it never works ?

      D Offline
      D Offline
      deleted286
      wrote on last edited by
      #11
      This post is deleted!
      mrjjM 1 Reply Last reply
      0
      • D deleted286

        This post is deleted!

        mrjjM Offline
        mrjjM Offline
        mrjj
        Lifetime Qt Champion
        wrote on last edited by
        #12

        @suslucoder
        Well it cant really be stuck as such.
        It means its current value is 15.

        You dont have any loops or anything that would prevent it from redrawing ?

        I think you will have to use the debugger and set breakpoint on the

        ui->progressBarXXXX

        and then see when you set data what it is.

        Its very unlikely the Widget simply don't redraw as that normally makes them white/odd if
        you have strangulated the event loop.

        D 1 Reply Last reply
        1
        • mrjjM mrjj

          @suslucoder
          Well it cant really be stuck as such.
          It means its current value is 15.

          You dont have any loops or anything that would prevent it from redrawing ?

          I think you will have to use the debugger and set breakpoint on the

          ui->progressBarXXXX

          and then see when you set data what it is.

          Its very unlikely the Widget simply don't redraw as that normally makes them white/odd if
          you have strangulated the event loop.

          D Offline
          D Offline
          deleted286
          wrote on last edited by
          #13

          @mrjj I didnt understand what you mean. Am i doing something wrong?

          mrjjM 1 Reply Last reply
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          • D deleted286

            @mrjj I didnt understand what you mean. Am i doing something wrong?

            mrjjM Offline
            mrjjM Offline
            mrjj
            Lifetime Qt Champion
            wrote on last edited by mrjj
            #14

            @suslucoder
            Hi
            Nope code looks fine but you seem think the widget would suddenly stop to draw and
            they rarely do and if they do, then it's very clear as it then looked messed up.

            So Im trying to guess at what could be wrong/go wrong.
            I think its just something with the data but you seems sure the values are newer and higher than 15 so
            I would like you to set a break point on the line where you set the progressbar value
            and then run & stop and inspect value in the dubugger to be truely sure that a value higher than 15 comes.

            other note, this line
            memcpy(dizi, data.constData(), 14);

            If less than 14 data comes, then old values are left in dizi.
            and what happens if data.constData() is less than 14 ?

            I think its something like that.

            D 1 Reply Last reply
            0
            • mrjjM mrjj

              @suslucoder
              Hi
              Nope code looks fine but you seem think the widget would suddenly stop to draw and
              they rarely do and if they do, then it's very clear as it then looked messed up.

              So Im trying to guess at what could be wrong/go wrong.
              I think its just something with the data but you seems sure the values are newer and higher than 15 so
              I would like you to set a break point on the line where you set the progressbar value
              and then run & stop and inspect value in the dubugger to be truely sure that a value higher than 15 comes.

              other note, this line
              memcpy(dizi, data.constData(), 14);

              If less than 14 data comes, then old values are left in dizi.
              and what happens if data.constData() is less than 14 ?

              I think its something like that.

              D Offline
              D Offline
              deleted286
              wrote on last edited by
              #15

              @mrjj data.constData() cant be less than 14. I set it. Its too weird

              mrjjM 1 Reply Last reply
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              • D deleted286

                @mrjj data.constData() cant be less than 14. I set it. Its too weird

                mrjjM Offline
                mrjjM Offline
                mrjj
                Lifetime Qt Champion
                wrote on last edited by mrjj
                #16

                @suslucoder
                Hi
                What you mean ?
                You dont set it at all

                QByteArray data = serial->readAll(); <<< this can read all from 1 to xxx bytes

                s= data.size(); << this is the size of data we read
                if (s>14)  << is is just some variable not related to data
                    s=14;
                

                then we copy 14 from data
                memcpy(dizi, data.constData(), 14);

                so it dont matter how much data we actually got. we always copy 14

                D 1 Reply Last reply
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                • mrjjM mrjj

                  @suslucoder
                  Hi
                  What you mean ?
                  You dont set it at all

                  QByteArray data = serial->readAll(); <<< this can read all from 1 to xxx bytes

                  s= data.size(); << this is the size of data we read
                  if (s>14)  << is is just some variable not related to data
                      s=14;
                  

                  then we copy 14 from data
                  memcpy(dizi, data.constData(), 14);

                  so it dont matter how much data we actually got. we always copy 14

                  D Offline
                  D Offline
                  deleted286
                  wrote on last edited by
                  #17

                  @mrjj said in UI doesnt refresh correctly:

                  @suslucoder
                  Hi
                  What you mean ?

                  I have

                  int16_t dizi[7];
                  

                  Since I have an array which size is 7, i wrote something

                  s= data.size(); 
                  if (s>14)  
                      s=14;
                  
                  mrjjM 1 Reply Last reply
                  0
                  • D deleted286

                    @mrjj said in UI doesnt refresh correctly:

                    @suslucoder
                    Hi
                    What you mean ?

                    I have

                    int16_t dizi[7];
                    

                    Since I have an array which size is 7, i wrote something

                    s= data.size(); 
                    if (s>14)  
                        s=14;
                    
                    mrjjM Offline
                    mrjjM Offline
                    mrjj
                    Lifetime Qt Champion
                    wrote on last edited by
                    #18

                    @suslucoder

                    But what do you then do with s to make it do anything ?

                    D 1 Reply Last reply
                    0
                    • mrjjM mrjj

                      @suslucoder

                      But what do you then do with s to make it do anything ?

                      D Offline
                      D Offline
                      deleted286
                      wrote on last edited by
                      #19

                      @mrjj Im just try to convert my binary data do int with that code script

                      mrjjM 1 Reply Last reply
                      0
                      • D deleted286

                        @mrjj Im just try to convert my binary data do int with that code script

                        mrjjM Offline
                        mrjjM Offline
                        mrjj
                        Lifetime Qt Champion
                        wrote on last edited by mrjj
                        #20

                        @suslucoder

                        ok im not sure what s does.

                        Anyway, could you try

                        (in on_Serial_Read)
                        memset(dizi, 0, 14);
                        memcpy(dizi, data.constData(), data.size());

                        in place ot the line
                        memcpy(dizi, data.constData(), 14);

                        and tell if it still stops at 15 ?

                        1 Reply Last reply
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