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Compose pointer to property of object

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c++pointerobjectsproperties
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  • M Offline
    M Offline
    McLion
    wrote on 5 Apr 2016, 10:03 last edited by
    #16

    Thanks for the heads-up.
    I'll do some testing and experiment.

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    0
    • M Offline
      M Offline
      McLion
      wrote on 5 Apr 2016, 14:16 last edited by
      #17

      So far, everything related to this threads question and the QMap as solution seems to work.

      I stumbled over something else while relacing the QwebView from the Designer by my 'on-demand' created one:
      I can not load an url, it crashes with sig11.

      I get the following connect error on bootup:

      QMetaObject::connectSlotsByName: No matching signal for on_webGUI_loadFinished(bool)
      

      which I dont understand and may be the cause.
      I have connected:

      connect(webGUI, SIGNAL(loadFinished(bool)), this, SLOT(on_webGUI_loadFinished(bool)));
      

      and in *.h as private slot:

      void on_webGUI_loadFinished(bool arg1);
      

      This worked before, with the QWebView from the Designer.
      Any idea? Thanks.

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      • M Offline
        M Offline
        mrjj
        Lifetime Qt Champion
        wrote on 5 Apr 2016, 14:26 last edited by
        #18

        @McLion said:

        no matching signal for on_webGUI_loadFinished(bool)

        Hi
        this warning comes as you name slot on_XXX
        This will trigger Qt auto connect feature so when you use
        a concrete connect you should rename it so it dont
        start with on__
        (right click it- refactor->rename)

        also please do
        qDebug() << "loadfin:" << connect(webGUI, SIGNAL(loadFinixxxx

        to see if it returns true; ( as in , it can connect)

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        • M Offline
          M Offline
          McLion
          wrote on 5 Apr 2016, 14:39 last edited by
          #19

          I wasn't aware that using on_ in the name will trigger any functionality!
          Refactoring solved this problem - Thanks !

          However, the signal 11 crash when trying to load an url seems to have some other cause .... I'm searching ;-)

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          • J Offline
            J Offline
            jsulm
            Lifetime Qt Champion
            wrote on 5 Apr 2016, 15:47 last edited by
            #20

            You're most probably dereferencing a null pointer. Signal 11 means SIGSEGV (segmentation error).

            https://forum.qt.io/topic/113070/qt-code-of-conduct

            M 1 Reply Last reply 6 Apr 2016, 08:21
            0
            • J jsulm
              5 Apr 2016, 15:47

              You're most probably dereferencing a null pointer. Signal 11 means SIGSEGV (segmentation error).

              M Offline
              M Offline
              McLion
              wrote on 6 Apr 2016, 08:21 last edited by
              #21

              @jsulm
              Yes - Thanks . Problem loacted, but not yet solved:

              void QTGUI_MainWindow::populateJavaScriptWindowObject()
              {
                QWebView * webGUI = qobject_cast<QWebView *>(sender());
                webGUI->page()->mainFrame()->addToJavaScriptWindowObject("NativeBridge", this);
              }
              

              The sender is the JS and not the QWebView and so I do not get the pointer to the QWebView that I need. Instead, the pointer is 0x0 and then - of course - the addToJ... crashes.

              Any idea how I get the pointer to the QWebView from which the JS is sending?
              Thanks

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              • J Offline
                J Offline
                jsulm
                Lifetime Qt Champion
                wrote on 6 Apr 2016, 08:42 last edited by
                #22

                What is JS?

                https://forum.qt.io/topic/113070/qt-code-of-conduct

                M 1 Reply Last reply 6 Apr 2016, 08:45
                0
                • J jsulm
                  6 Apr 2016, 08:42

                  What is JS?

                  M Offline
                  M Offline
                  McLion
                  wrote on 6 Apr 2016, 08:45 last edited by
                  #23

                  @jsulm
                  JavaScript (in/from QWebKit ... more precise page()->mainFrame().

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                  • M Offline
                    M Offline
                    McLion
                    wrote on 6 Apr 2016, 11:33 last edited by
                    #24

                    I posted this as a separate question in the WebKit group.

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                    • M Offline
                      M Offline
                      McLion
                      wrote on 6 Apr 2016, 14:57 last edited by
                      #25

                      Got it solved :-)

                      QWebFrame * webGUIframe = qobject_cast<QWebFrame >(sender());
                      QWebView * webGUI = (QWebView
                      )(webGUIframe->parent())->parent();
                      webGUI->page()->mainFrame()->addToJavaScriptWindowObject("NativeBridge", this);

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                      6 Apr 2016, 14:57

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