Dialog before main window (i.e. a wizard)

SeeLook

Hi,

I'm looking for the best solution to display a wizard window before a main application window. So far, this is my solution:

// main.cpp
auto a = new QApplication(argc, argv);
// (....)
auto e = new QQmlApplicationEngine;
e->rootContext()->setContextProperty(QStringLiteral("GLOB"), GLOB); // some global object for entire QML code
e->rootContext()->setContextProperty(QStringLiteral("otherGlobal"), &otherGlobal);
if (GLOB->isFirstRun) {
  e->load(QUrl(QStringLiteral("qrc:/Wizard.qml")));
  a->exec();
  delete e;
  e = new QQmlApplicationEngine;
  e->rootContext()->setContextProperty(QStringLiteral("GLOB"), GLOB);
  e->rootContext()->setContextProperty(QStringLiteral("otherGlobal"), &otherGlobal);;
  GLOB->isFirstRun = false;
 }
 e->load(QUrl(QStringLiteral("qrc:/MainWindow.qml")));
a->exec();
(....)

This way I'm calling QApplication::exec() twice, but it seems to not be a problem.
But there is also a need to delete first instance of QQmlApplicationEngine - otherwise the wizard instance is not destroyed, it disappears only.
So when the engine instance is created again, I have to again load e->rootContext()->setContextProperty() with those shared objects.

It works fine, but maybe there is any better way to invoke the wizard before main app window.