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How to pass the parameters between the SIGNAL and SLOTS

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  • A Offline
    A Offline
    Alex42
    wrote on last edited by
    #7

    for more information , i created the principle interface (MainWindow), and in this interface i have two QPushbutton ,the first button open the firste interface (Mesure) , and the second Button open the seconde interface

    • i don't get any messages about the connect failing
      -( i can to change the data between the firste interface (Mesure) and the seconde interface (Mesureone ), but with the QLineEdit i can't to transmite data between this interfaces
    • i used the debugger , and the slot is called and the connect executed . But i can't to interact between this interfaces with the QLineEdit (incredible)
    mrjjM 1 Reply Last reply
    0
    • A Alex42

      for more information , i created the principle interface (MainWindow), and in this interface i have two QPushbutton ,the first button open the firste interface (Mesure) , and the second Button open the seconde interface

      • i don't get any messages about the connect failing
        -( i can to change the data between the firste interface (Mesure) and the seconde interface (Mesureone ), but with the QLineEdit i can't to transmite data between this interfaces
      • i used the debugger , and the slot is called and the connect executed . But i can't to interact between this interfaces with the QLineEdit (incredible)
      mrjjM Offline
      mrjjM Offline
      mrjj
      Lifetime Qt Champion
      wrote on last edited by
      #8

      @Alex42

      Hi
      Your connect seems to be called many times.
      Normally you should only call it once as it will send multiple times if you connect multiple times and
      that is normally not what you want.

      Anyway,

      Are you saying that

      void Mesure :: calculate_3 ()
      {
      
          S++;
      
          if (S>0)
          {
          emit newtextChanged_1(QString::number (ui->lcdNumber_1->value()));  /// works
          but  
          emit newtextChanged_1(mence->text()); // wont work ?
      
      
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      • A Offline
        A Offline
        Alex42
        wrote on last edited by
        #9

        @mrjj said in How to pass the parameters between the SIGNAL and SLOTS:

        Your connect seems to be called many times.

        there is no probleme if you call it many time or you call it once , i tried many situation ( call it once , and call it many time ) but that not work

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        • A Offline
          A Offline
          Alex42
          wrote on last edited by
          #10

          @mrjj said in How to pass the parameters between the SIGNAL and SLOTS:

          emit newtextChanged_1(mence->text()); // wont work ?

          emit newtextChanged_1(mence->text()); // wont work ? exactly what i whant to do buthe d'ont work

          mrjjM 1 Reply Last reply
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          • A Alex42

            @mrjj said in How to pass the parameters between the SIGNAL and SLOTS:

            emit newtextChanged_1(mence->text()); // wont work ?

            emit newtextChanged_1(mence->text()); // wont work ? exactly what i whant to do buthe d'ont work

            mrjjM Offline
            mrjjM Offline
            mrjj
            Lifetime Qt Champion
            wrote on last edited by
            #11

            @Alex42

            Hi
            does
            QString test("hello");
            emit newtextChanged_1(test);

            works ?

            Both should work if the
            QString::number (ui->lcdNumber_1->value()) works.

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            • A Offline
              A Offline
              Alex42
              wrote on last edited by
              #12

              @mrjj , QString test("hello");
              emit newtextChanged_1(test);

              works ?

              yes it works very well

              mrjjM 1 Reply Last reply
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              • A Offline
                A Offline
                Alex42
                wrote on last edited by
                #13

                are you undestad that may QLineEdite change every 1000ms ?

                1 Reply Last reply
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                • A Alex42

                  @mrjj , QString test("hello");
                  emit newtextChanged_1(test);

                  works ?

                  yes it works very well

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

                  @Alex42

                  Ok that is a bit o.O

                  so try

                  QString text = mence->text();
                  qDebug() << "sending:" << text;
                  emit ewtextChanged_1(text);

                  and see if the mence is the one you think it is as that is my only guess then as
                  the signal clearly works :)

                  Yes, I understand you change the text of the lineEdit every sec,but that should not matter
                  as we just get what ever was set last when we ask.

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                  • A Offline
                    A Offline
                    Alex42
                    wrote on last edited by
                    #15

                    yes exactly what i want , befor i tried this and works very well ,
                    but the probleme is in the second interface i can't receve this data ![alt text](d1227136-64f2-4151-9673-f2de8d04d62e-Capture.PNG image url)
                    ( in the seconde interface i receve only 0( the fiste values) , i can't receive the values when is chenged

                    mrjjM 1 Reply Last reply
                    0
                    • A Alex42

                      yes exactly what i want , befor i tried this and works very well ,
                      but the probleme is in the second interface i can't receve this data ![alt text](d1227136-64f2-4151-9673-f2de8d04d62e-Capture.PNG image url)
                      ( in the seconde interface i receve only 0( the fiste values) , i can't receive the values when is chenged

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

                      @Alex42

                      So in interface 2, you only see the "0" and never "12222" etc ?

                      But you could send "hello" and other string ?
                      That I cant explain. seems impossible.

                      Just so I understand.

                      You have a main window and 2 buttons. Each button opens a new Form/window and
                      form1 has a timer or something that makes a lineEdit count/set some value.
                      This value you try to emit to form2 when calculate_3 is called ?

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                      • A Offline
                        A Offline
                        Alex42
                        wrote on last edited by
                        #17

                        @mrjj said in How to pass the parameters between the SIGNAL and SLOTS:

                        So in interface 2, you only see the "0" and never "12222" etc ?

                        So in interface 2, you only see the "0" and never "12222" etc ? yes exactly
                        But you could send "hello" and other string ? yes i can send hello
                        You have a main window and 2 buttons. Each button opens a new Form/window and
                        form1 has a timer or something that makes a lineEdit count/set some value.
                        This value you try to emit to form2 when calculate_3 is called ? exactly what i want to do

                        mrjjM 1 Reply Last reply
                        0
                        • A Alex42

                          @mrjj said in How to pass the parameters between the SIGNAL and SLOTS:

                          So in interface 2, you only see the "0" and never "12222" etc ?

                          So in interface 2, you only see the "0" and never "12222" etc ? yes exactly
                          But you could send "hello" and other string ? yes i can send hello
                          You have a main window and 2 buttons. Each button opens a new Form/window and
                          form1 has a timer or something that makes a lineEdit count/set some value.
                          This value you try to emit to form2 when calculate_3 is called ? exactly what i want to do

                          mrjjM Offline
                          mrjjM Offline
                          mrjj
                          Lifetime Qt Champion
                          wrote on last edited by
                          #18

                          @Alex42
                          Ok. how is the LineEdit updated ?
                          a Qtimer ?

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                          • A Offline
                            A Offline
                            Alex42
                            wrote on last edited by
                            #19

                            yes a Qtimer

                            mrjjM 1 Reply Last reply
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                            • A Alex42

                              yes a Qtimer

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

                              @Alex42

                              Ok. hang on for 20 mins. Ill try myself as it does seem strange :)

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                              • A Offline
                                A Offline
                                Alex42
                                wrote on last edited by
                                #21

                                @mrjj said in How to pass the parameters between the SIGNAL and SLOTS:

                                Ok. hang on for 20 mins. Ill try myself as it does seem strange :)

                                ok thank you very match for your helpe

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                                • A Offline
                                  A Offline
                                  Alex42
                                  wrote on last edited by
                                  #22

                                  i'm sorry, i have a lot of classe , methode and line of code, and there is interaction between them with QTimer , Mathematique fonction ...etc , for this i can't to post all my code

                                  mrjjM 1 Reply Last reply
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                                  • A Alex42

                                    i'm sorry, i have a lot of classe , methode and line of code, and there is interaction between them with QTimer , Mathematique fonction ...etc , for this i can't to post all my code

                                    mrjjM Offline
                                    mrjjM Offline
                                    mrjj
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #23

                                    @Alex42
                                    Thats ok.
                                    I will make a fast example and if that just works, you can have it and have a look.
                                    Maybe we can find out what the difference it. :)

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                                    • A Offline
                                      A Offline
                                      Alex42
                                      wrote on last edited by
                                      #24

                                      OK , thank you

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                                      • mrjjM Offline
                                        mrjjM Offline
                                        mrjj
                                        Lifetime Qt Champion
                                        wrote on last edited by
                                        #25

                                        hi
                                        Seems to work fine even with a 100 MS timer so should work for you too.

                                        Can you please try ?

                                        https://www.dropbox.com/s/l8go4t71unosl05/CrossTalk.zip?dl=0

                                        alt text

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                                        • A Offline
                                          A Offline
                                          Alex42
                                          wrote on last edited by
                                          #26

                                          ok , can you show me your code please ;

                                          mrjjM 1 Reply Last reply
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