Access a member function using QQuickWindow - qt

Question

I have set ObjectName to a class in main and want to access this object from another class:
main.cpp
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
QQmlApplicationEngine engine;
ImageProvider *imageProvider = new ImageProvider(&engine,QQmlImageProviderBase::Image,0);
PageBuffer p;
p.setObjectName("Object");
engine.rootContext()->setContextProperty("p",&p);
engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
engine.addImageProvider("images", imageProvider);
return app.exec();
}
The class where i am trying to access PageBuffer p from:
QImage ImageProvider ::requestImage(const QString &id, QSize *size, const QSize &requestedSize)
{
QQuickWindow *window = qobject_cast<QQuickWindow*>(m_engine->rootObjects()[0]);
PageBuffer *p = window->findChild<PageBuffer *>("Object");
cout<<p->current_box; //error at runtime
QImage e;
e.load("Pic4.jpg");
return e;
}
But i cant seem to access any member of the object PageBuffer, maybe because of pointers, how can can i access the functions from the object p?

Answer 1

You could just introduce a pageBuffer member to ImageProvider:
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
QQmlApplicationEngine engine;
ImageProvider *imageProvider = new ImageProvider(&engine,QQmlImageProviderBase::Image,0);
PageBuffer p;
imageProvider->setPageBuffer(p);
engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
engine.addImageProvider("images", imageProvider);
return app.exec();
}
Then you don't need to search for object children, you can access pageBuffer directly:
QImage ImageProvider::requestImage(const QString &id, QSize *size, const QSize &requestedSize)
{
QQuickWindow *window = qobject_cast<QQuickWindow*>(m_engine->rootObjects()[0]);
PageBuffer *p = pageBuffer();
cout << p->current_box;
QImage e;
e.load("Pic4.jpg");
return e;
}