Cannot execute examples from Doc

AlainBo

Hello,

I'm trying to learn about connections between QML and C++ and I don't understand why I cannot get the examples from doc working.

For example, I try to use this simple example.

So my full main.cpp code is:

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QQuickView>

class MyClass : public QObject
{
    Q_OBJECT
public slots:
    void cppSlot(const QString &msg) {
        qDebug() << "Called the C++ slot with message:" << msg;
    }
};

int main(int argc, char *argv[]) {
    QGuiApplication app(argc, argv);

    QQuickView view(QUrl::fromLocalFile("MyItem.qml"));
    QObject *item = view.rootObject();

    MyClass myClass;
    QObject::connect(item, SIGNAL(qmlSignal(QString)),
                     &myClass, SLOT(cppSlot(QString)));

    view.show();
    return app.exec();
}

And when I try to build it, I get the following errors:

main.cpp:18: error: cannot initialize a variable of type 'QObject *' with an rvalue of type 'QQuickItem *'
main.cpp:-1: In function 'int qMain(int, char**)':
main.cpp:18: error: cannot convert 'QQuickItem*' to 'QObject*' in initialization
     QObject *item = view.rootObject();
                                     ^
D:\Qt\5.12.6\mingw73_64\include\QtQuick\qquickview.h:43: In file included from D:\Qt\5.12.6\mingw73_64\include\QtQuick/qquickview.h:43:0,
D:\Qt\5.12.6\mingw73_64\include\QtQuick\QQuickView:1: from D:\Qt\5.12.6\mingw73_64\include\QtQuick/QQuickView:1,
main.cpp:3: from ..\test2\main.cpp:3:
D:\Qt\5.12.6\mingw73_64\include\QtQuick\qquickwindow.h:55: class type 'QQuickItem' is incomplete
 class QQuickItem;
       ^~~~~~~~~~

How to solve it and why is it so complex to use examples?

Regards

aha_1980

Hi @AlainBo

please show your project .pro file.

Regards

ODБOï

@AlainBo said in Cannot execute examples from Doc:

'QQuickItem' is incomplete

include QQuickItem

Nando

@LeLev That fixes it, thank you.
The creator should set this thread as resolved....