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Extending qml with c++

  • I am learning how to extend qml with c++ and I have been trying the solutions online but I am stuck with this error

    module "" is not installed

    Below is my project file, Can someone help me out please?

    QT += quick qml widgets
    CONFIG += c++11 q t plugin
    # The following define makes your compiler emit warnings if you use
    # any Qt feature that has been marked deprecated (the exact warnings
    # depend on your compiler). Refer to the documentation for the
    # deprecated API to know how to port your code away from it.
    DESTDIR = QmlWithCpp
    # You can also make your code fail to compile if it uses deprecated APIs.
    # In order to do so, uncomment the following line.
    # You can also select to disable deprecated APIs only up to a certain version of Qt.
    #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
    TARGET = fileioplugin
    SOURCES += \
            fileio.cpp \
            fileioplugin.cpp \
    RESOURCES += qml.qrc
    # Additional import path used to resolve QML modules in Qt Creator's code model
    # Additional import path used to resolve QML modules just for Qt Quick Designer
    # Default rules for deployment.
    qnx: target.path = /tmp/$${TARGET}/bin
    else: unix:!android: target.path = /opt/$${TARGET}/bin
    !isEmpty(target.path): INSTALLS += target
    HEADERS += \
        fileio.h \
    DISTFILES += \

  • Can you show us your main()?

  • #include <QGuiApplication>
    #include <QQmlApplicationEngine>

    int main(int argc, char *argv[])

    QGuiApplication app(argc, argv);
    QQmlApplicationEngine engine;
    const QUrl url(QStringLiteral("qrc:/main.qml"));
    QObject::connect(&engine, &QQmlApplicationEngine::objectCreated,
                     &app, [url](QObject *obj, const QUrl &objUrl) {
        if (!obj && url == objUrl)
    }, Qt::QueuedConnection);
    return app.exec();


    Sorry for the late reply, this is the main file.I am using the plugin approach

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