qt-creator/share/qtcreator/templates/qtquick2app/main.cpp

#include <QtGui/QGuiApplication>
#include "qtquick2applicationviewer.h"

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

    QtQuick2ApplicationViewer viewer;
    viewer.setMainQmlFile(QStringLiteral("qml/app/qtquick20/main.qml")); // MAINQML
    viewer.showExpanded();

    return app.exec();
}