QML application - c++

Question

My program has two modes GUI(on qml) and no GUI(command line).What code I must write for changing mode by passing argument in cmd
for example if I pass nameofapp.exe -no-gui must be work no-gui version
for simple qt/c++ application we have this code
QCoreApplication* createApplication(int &argc, char *argv[])
{
for (int i = 1; i < argc; ++i)
if (!qstrcmp(argv[i], "-no-gui"))
return new QCoreApplication(argc, argv);
return new QApplication(argc, argv);
}
int main(int argc, char* argv[])
{
QScopedPointer<QCoreApplication> app(createApplication(argc, argv));
if (qobject_cast<QApplication *>(app.data())) {
// start GUI version...
} else {
// start non-GUI version...
}
return app->exec();
}
It's from documentation,I want such of this for qml
OS is windows 7 ultimate but I don't think that it's depends on OS

Answer 1

You need at least one top level QObject per application type which will "make things happen" in the main event loop.
Assuming that you have made a clear separation of concern between the view and the backend (eg MVC), you will have 3 classes (which are QObject) :
MyAppBackend which does the actual work
MyGUIMainWindow which manage GUI input\outpout.
MyCLIMainObject which manage command line input\outpout
Each one should have a method to start doing work. For instance just showing a widget is how simple Qt apps start.
int main()
{
QApplication app;
MyGUIMainWindow window;
window.show();
return app.exec();
}
window.show() will queue an event which will be processed when app.exec(). is executed.
You need to do the same with a function which either post an event or emit a signal.
int main(int argc, char* argv[])
{
QScopedPointer<QCoreApplication> app(createApplication(argc, argv));
MyAppBackend backend;
backend.startDeffered();
if (qobject_cast<QApplication *>(app.data())) {
// start GUI version...
MyGUIMainWindow* window = new MyGUIMainWindow(0,...);
window->show();
} else {
// start non-GUI version...
MyCLIMainObject* cliobj = new MyCLIMainObject(0,...);
cliobj->showCLi();
}
return app->exec();
}