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Passing another argument to a SLOT

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  • P Offline
    P Offline
    Phenixo
    wrote on last edited by
    #7

    I have read the qsignalmapper class in the exemple it show how pass one argument the cliqued signal don't pass an argument
    i want to pass two variable the QString from the titilechanged and the int from my methode

    to be a professional programmer is my goal :p

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

      Like the others said, it's not possible to have a slot with more arguments than the signal.

      Use an intermediate slot that will call your function with the necessary parameters.

      Also, are you sure you want to use pointers to QString and int in your slot ?

      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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      • P Offline
        P Offline
        Phenixo
        wrote on last edited by
        #9

        @void mainWind::changetab(int index)
        {
        if(ui->tabWidget->indexOf(ui->newtab)==index)
        {
        addtab();

        }
        

        currentpage(()->settings()->setIconDatabasePath("a");
        url(currentPages()->url());
        connect(currentpage((),SIGNAL(loadProgress(int)),ui->progressBar,SLOT(setValue(int)));
        connect(currentpage((),SIGNAL(loadStarted()),this,SLOT(depart()));
        connect(currentpage((),SIGNAL(loadFinished(bool)),this,SLOT(finish(bool)));
        connect(currentpage((),SIGNAL(loadProgress(int)),this,SLOT(laodPage(int)));
        connect(currentpage((),SIGNAL(titleChanged(QString)),this,SLOT(titl(QString)));
        connect(currentpage((),SIGNAL(urlChanged(QUrl)),this,SLOT(url(QUrl)));
        connect(currentpage((),SIGNAL(iconChanged()),this,SLOT(icon()));

        }@
        @
        QWebView *mainWind:: currentpage()
        {
        if(ui->tabWidget->currentWidget()->findChild<QWebView *>()==0)
        {
        int a=ui->tabWidget->currentIndex()-1;
        return ui->tabWidget->widget(a)->findChild<QWebView *>();

        }
        else
        {
            return ui->tabWidget->currentWidget()->findChild<QWebView *>();
        }
        

        }
        @
        @
        void mainWind::titre(const QString & titre)
        {
        QString titr(titre);
        if(titre.size()>40)
        {
        titr=titre.left(40)+"....";
        }
        ui->tabWidget->setTabText(m_index,titr);
        }
        @
        so when i load a page and I dont change the tab all is ok. but when i leave the page to load and i change the tab. the name of the page load is in the newtab because it is now the current tab. i have the page in a tab and its name in the other tab.
        so thats why i want to pass index of the widget (that well be changing the titl

        to be a professional programmer is my goal :p

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

          Then in your slot use sender() to get the widget that emitted the signal and use that to find the right tab to update.

          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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          • P Offline
            P Offline
            Phenixo
            wrote on last edited by
            #11

            thx for answering my question
            if you can please tell me how to use the sender i have read the doc but i didn't understand very well can you please give me a simple example in general.

            to be a professional programmer is my goal :p

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

              sender() returns a pointer to the object that emitted the signal. In your case (if I understood correctly) it's one of the widget in the QTabWidget.

              You can cast (using qobject_cast) that pointer to QWidget * and then get the tab index using indexOf and update the correct tab text with 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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              • P Offline
                P Offline
                Phenixo
                wrote on last edited by
                #13

                thx
                [quote author="SGaist" date="1377806355"]sender() returns a pointer to the object that emitted the signal. In your case (if I understood correctly) it's one of the widget in the QTabWidget. [/quote]

                but the QObject that emitted the signal is a QWebView which is contain in a QTabWidget can i have a access to the tab with a pointer of QWebView
                fanction like "findChild" but in this one i have to find the parent
                thx again

                to be a professional programmer is my goal :p

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

                  You don't need that, since you call addTab with a QWebView you can retrieve the corresponding index with the pointer given by sender() once you casted 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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                  • P Offline
                    P Offline
                    Phenixo
                    wrote on last edited by
                    #15

                    QObject * QObject::sender() const [protected] where do i declare this methode, in which slot.
                    i have also this slot
                    @void mainWind::addtap()
                    {
                    QWidget *tap=new QWidget();
                    QVBoxLayout *layout = new QVBoxLayout();
                    QWebView *webpage=new QWebView();
                    pageWeb->settings()->setIconDatabasePath("a");
                    layout->addWidget(webpage);
                    tap->setLayout(layout);
                    webpage->load(QUrl(""));
                    ui->tabWidget->insertTab(ui->tabWidget->indexOf(ui->newTap),tap,"");
                    ui->tabWidget->setCurrentWidget(tap);
                    changetap(ui->tabWidget->indexOf(tap));

                    }@

                    to be a professional programmer is my goal :p

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                    • SGaistS Offline
                      SGaistS Offline
                      SGaist
                      Lifetime Qt Champion
                      wrote on last edited by
                      #16

                      You don't declare that method. You call it at the start of the slot

                      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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                      • K Offline
                        K Offline
                        KA51O
                        wrote on last edited by
                        #17

                        see the doc of "QObject::sender()":http://qt-project.org/doc/qt-4.8/qobject.html#sender .

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                        • P Offline
                          P Offline
                          Phenixo
                          wrote on last edited by
                          #18

                          @void mainWind::titre(const QString & titre)
                          {
                          QWidget *a= qobject_cast<QWidget *>(sender());
                          QString titr(titre);
                          if(titre.size()>40)
                          {
                          titr=titre.left(40)+"....";
                          }
                          ui->tabWidget->setTabText(ui->tabWidget->indexOf(a)),titr);
                          }@
                          is this correct

                          to be a professional programmer is my goal :p

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