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signal and slots between two classes

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  • M Offline
    M Offline
    marlenet15
    wrote on last edited by
    #3
    This post is deleted!
    mrjjM 1 Reply Last reply
    0
    • M marlenet15

      This post is deleted!

      mrjjM Offline
      mrjjM Offline
      mrjj
      Lifetime Qt Champion
      wrote on last edited by
      #4

      @marlenet15
      Ok, as far as I know you cannot connect signal to signal but you can
      connect multiple signals to one slot.

      Did you place break point to see if the DoNext is called and
      also check in application output that none of the connets return fail.
      maybe even
      qDebug() << " result:" << connect(ui->nextButtonSignin, SIGNAL(clicked()),this,SLOT(DoNext())); for both connect to see
      if they are successful.

      JKSHJ 1 Reply Last reply
      0
      • mrjjM mrjj

        Hi
        One thing I saw
        connect(ui->nextButtonSignin, SIGNAL(clicked()),this,SIGNAL(clickedNextSignal()));
        should have been SLOT in last.

        If possible, use the new syntax as it has more type checking

        connect( ui->nextButtonSignin, &QPushButton::clicked, this, &Dialog::clickedNextSignal);
        (If nextButtonSignin is QPushbutton)

        Hmm, there is something odd going on:
        signin has signal clickedNextSignal but you never call
        emit clickedNextSignal()
        so in Dialog::Dialog
        when you say
        connect(_signin , SIGNAL(clickedNextSignal()),this,SLOT(openBox()));
        Its correct but since signin do not emit (send) signal then nothing will happen.

        So if you add a slot to sign in, lets cal lit DoNext (bad name:)
        and hook it up to the button
        connect(ui->nextButtonSignin, SIGNAL(clicked()),this,SLOT(DoNext()));
        and in
        void DoNext() {
        emit clickedNextSignal();
        }
        Then the connect in Dialog should be more fun,
        So in short.
        NextButton clicked goes to signin slot that emit clickedNextSignal signal , that is hooked up to Dialog openBox().

        Hope it helps.

        M Offline
        M Offline
        marlenet15
        wrote on last edited by
        #5

        @mrjj I read from somewhere that you can have connect with two signals. I did try your recommendation but nothing happens.

        1 Reply Last reply
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        • mrjjM Offline
          mrjjM Offline
          mrjj
          Lifetime Qt Champion
          wrote on last edited by mrjj
          #6

          also how does you main.cpp look like ?

          You show the Dialog instead of mainwindow?

          M 1 Reply Last reply
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          • mrjjM mrjj

            also how does you main.cpp look like ?

            You show the Dialog instead of mainwindow?

            M Offline
            M Offline
            marlenet15
            wrote on last edited by
            #7

            @mrjj

            #include "dialog.h"
            #include <QApplication>
            
            int main(int argc, char *argv[])
            {
                QApplication a(argc, argv);
                Dialog *w = new Dialog();
                w->showNormal();
            
                return a.exec();
            }``` 
            
            and yes I used Dialog instead of mainwindow
            mrjjM 1 Reply Last reply
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            • M marlenet15

              @mrjj

              #include "dialog.h"
              #include <QApplication>
              
              int main(int argc, char *argv[])
              {
                  QApplication a(argc, argv);
                  Dialog *w = new Dialog();
                  w->showNormal();
              
                  return a.exec();
              }``` 
              
              and yes I used Dialog instead of mainwindow
              mrjjM Offline
              mrjjM Offline
              mrjj
              Lifetime Qt Champion
              wrote on last edited by
              #8

              @marlenet15 said:
              Hi I think the dialog in dialog mess up something.
              Didnt work for me if I new the sign dialog in Start dialog constructor.
              But it does work if I hooked it up outside.
              Have a look at this example
              https://www.dropbox.com/s/bvpps7qd8oovtjf/gonext.zip?dl=0
              Its the same idea but created slightly different.

              M 1 Reply Last reply
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              • mrjjM mrjj

                @marlenet15 said:
                Hi I think the dialog in dialog mess up something.
                Didnt work for me if I new the sign dialog in Start dialog constructor.
                But it does work if I hooked it up outside.
                Have a look at this example
                https://www.dropbox.com/s/bvpps7qd8oovtjf/gonext.zip?dl=0
                Its the same idea but created slightly different.

                M Offline
                M Offline
                marlenet15
                wrote on last edited by
                #9

                @mrjj I followed your example but it is still not working.

                mrjjM 1 Reply Last reply
                0
                • M marlenet15

                  @mrjj I followed your example but it is still not working.

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

                  @marlenet15
                  ??
                  so the getnext example which runs here do no work when you compile it?

                  M 1 Reply Last reply
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                  • mrjjM mrjj

                    @marlenet15
                    ??
                    so the getnext example which runs here do no work when you compile it?

                    M Offline
                    M Offline
                    marlenet15
                    wrote on last edited by
                    #11

                    @mrjj ok it works. I redid my code using only QWidgets and it works. I think I know the problem and I forgot to mention it. I made QDialog a stacked widget and promoted the file signin.

                    1 Reply Last reply
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                    • mrjjM mrjj

                      @marlenet15
                      Ok, as far as I know you cannot connect signal to signal but you can
                      connect multiple signals to one slot.

                      Did you place break point to see if the DoNext is called and
                      also check in application output that none of the connets return fail.
                      maybe even
                      qDebug() << " result:" << connect(ui->nextButtonSignin, SIGNAL(clicked()),this,SLOT(DoNext())); for both connect to see
                      if they are successful.

                      JKSHJ Offline
                      JKSHJ Offline
                      JKSH
                      Moderators
                      wrote on last edited by JKSH
                      #12

                      @mrjj said:

                      Ok, as far as I know you cannot connect signal to signal

                      You can. See the documentation:

                      You can connect as many signals as you want to a single slot, and a signal can be connected to as many slots as you need. It is even possible to connect a signal directly to another signal. (This will emit the second signal immediately whenever the first is emitted.)

                      Qt Doc Search for browsers: forum.qt.io/topic/35616/web-browser-extension-for-improved-doc-searches

                      mrjjM 1 Reply Last reply
                      1
                      • JKSHJ JKSH

                        @mrjj said:

                        Ok, as far as I know you cannot connect signal to signal

                        You can. See the documentation:

                        You can connect as many signals as you want to a single slot, and a signal can be connected to as many slots as you need. It is even possible to connect a signal directly to another signal. (This will emit the second signal immediately whenever the first is emitted.)

                        mrjjM Offline
                        mrjjM Offline
                        mrjj
                        Lifetime Qt Champion
                        wrote on last edited by
                        #13

                        @JKSH
                        Aha, that is news for me. so that is like a chain signal or almost like an alias.

                        @marlenet15
                        Super. not sure what the real reason was but as long as it works :)

                        M 1 Reply Last reply
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                        • mrjjM mrjj

                          @JKSH
                          Aha, that is news for me. so that is like a chain signal or almost like an alias.

                          @marlenet15
                          Super. not sure what the real reason was but as long as it works :)

                          M Offline
                          M Offline
                          marlenet15
                          wrote on last edited by
                          #14

                          @mrjj Before creating the stackedwidget it worked. After adding it, it doesn't work anymore.

                          mrjjM 1 Reply Last reply
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                          • M marlenet15

                            @mrjj Before creating the stackedwidget it worked. After adding it, it doesn't work anymore.

                            mrjjM Offline
                            mrjjM Offline
                            mrjj
                            Lifetime Qt Champion
                            wrote on last edited by
                            #15

                            @marlenet15
                            Ok. do you promote a qDialog to a stackwidget ?
                            Not sure I fully understand.
                            At least I have never tried that.

                            M 1 Reply Last reply
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                            • mrjjM mrjj

                              @marlenet15
                              Ok. do you promote a qDialog to a stackwidget ?
                              Not sure I fully understand.
                              At least I have never tried that.

                              M Offline
                              M Offline
                              marlenet15
                              wrote on last edited by
                              #16

                              @mrjj on the .ui file of the class dialog, I created a stackedwidget and promoted the file signin.h

                              mrjjM 1 Reply Last reply
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                              • M marlenet15

                                @mrjj on the .ui file of the class dialog, I created a stackedwidget and promoted the file signin.h

                                mrjjM Offline
                                mrjjM Offline
                                mrjj
                                Lifetime Qt Champion
                                wrote on last edited by
                                #17

                                @marlenet15
                                so the signin dialog was sort of inline to Dialog ?

                                M 1 Reply Last reply
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                                • mrjjM mrjj

                                  @marlenet15
                                  so the signin dialog was sort of inline to Dialog ?

                                  M Offline
                                  M Offline
                                  marlenet15
                                  wrote on last edited by
                                  #18

                                  @mrjj can you exaplain what you mean by that? Sorry

                                  mrjjM 1 Reply Last reply
                                  0
                                  • M marlenet15

                                    @mrjj can you exaplain what you mean by that? Sorry

                                    mrjjM Offline
                                    mrjjM Offline
                                    mrjj
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #19

                                    @marlenet15
                                    Hi np.
                                    Im not 100% sure what you did.
                                    If you promote a widget to a dialog.
                                    the dialog will be sort of inside the parent/widget that contains the
                                    promoted widget.
                                    So I wondered if you promoted a stacked widget to the signin dialog ?

                                    M 1 Reply Last reply
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                                    • mrjjM mrjj

                                      @marlenet15
                                      Hi np.
                                      Im not 100% sure what you did.
                                      If you promote a widget to a dialog.
                                      the dialog will be sort of inside the parent/widget that contains the
                                      promoted widget.
                                      So I wondered if you promoted a stacked widget to the signin dialog ?

                                      M Offline
                                      M Offline
                                      marlenet15
                                      wrote on last edited by
                                      #20

                                      @mrjj I created a stackedwidget in dialog.ui, in there I promoted signin.h into the stackedwidget.

                                      JKSHJ 1 Reply Last reply
                                      0
                                      • mrjjM Offline
                                        mrjjM Offline
                                        mrjj
                                        Lifetime Qt Champion
                                        wrote on last edited by mrjj
                                        #21

                                        ahh that way. Hmm should be the same as using a plain qwidget but seems it was not.

                                        Can I ask what kind of design u are after ?
                                        like sort of custom wizard style thing ?

                                        M 1 Reply Last reply
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                                        • mrjjM mrjj

                                          ahh that way. Hmm should be the same as using a plain qwidget but seems it was not.

                                          Can I ask what kind of design u are after ?
                                          like sort of custom wizard style thing ?

                                          M Offline
                                          M Offline
                                          marlenet15
                                          wrote on last edited by
                                          #22

                                          @mrjj yes I am. I am doing something simple now in order to understand how it works so that later I can use it so that when i click the button, it goes to the next page.

                                          mrjjM 1 Reply Last reply
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