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QApplication crashes when aboutQt dialog is closed.

  • Hi there,

    I'm showing the aboutQt dialog in my App using QApplication::aboutQt(). Unfortunately everytime when I close this dialog my app crashes.

    I've connected it to QML and calling it via simple Signal-Slot-connection:

    connect(this, SIGNAL(qtAboutScreen()), qApp, SLOT(aboutQt()));

    The class which is connected to QApplication inherits from QObject. Is there any Problem? Or do you know other, better solutions to display Qt information in qml?


  • Lifetime Qt Champion

    When the program crashes you can take a look what the debugger tells you. From your code above we can't say anything about what's going wrong. So provide more code, the best would be a minimal, compilable example to show your problem.

  • There is no output except the "program has unexpectedly finished" message. The debugger gets stuck in Disassembler (QV4::ExecutionEngine::newString(QString const&)).

    I'm doing nothing else than connecting a signal to the QApplication::aboutQt() slot. After closing the About Dialog the error appears.

  • Lifetime Qt Champion

    QV4 looks like QML somwhere.
    Reduce you app until it no longer crashes, the connect is for sure not the problem.

  • Ok it was my fault. I've used a Q_INVOKABLE method which should return a QString but returned nothing.

    Nevertheless I didn't used the QApplication::aboutQt() function to show the licensing information, because it opens a dialog with a completely different look and feel (QWidget).

    Instead I created a Qml Popup and used QT_VERSION_STR to get the current qt version.

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