You have an error in your .pro file. Right after the QT += opengl line you have QT = core gui which resets the content of the variable to core gui. That's why you can't get the OpenGL module.

Hi Main windows is a bit special since it has "central widget". which there to allow to define areas around it for Dock windows. That is why we insert widget first. For all types of other widget we would insert directly. QWidget* centralWidget = new QWidget(); QVBoxLayout *layout = new QVBoxLayout; centralWidget->setLayout(layout); layout->addWidget(st); setCentralWidget(centralWidget); seems fine. For centralWidget , u can then use the Stacked. My mainWindow code actually looks like: MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow) { setLayout(layout); // that sets directly on mainwin. not sure it does what we think. You can just single step and see the values to find out why u crash. Sorry, i cant spot it. Running it helps. I think u need a setCentral also. That is the reason no 2 to why i like UI file so much. no crashing as u can only insert legally when visually :) And no code to try to spot bugs in. I think u need new widget widget as central new layout layout to widget inset stacked to that layout and then the page stuff

@MarceloGomez my skype is nostrik7180 . Can we discuss about your project ?

@kshegunov I know I know ^^and normally I don't pay much attention to this but.. this time wanted to point it out... dunno why hahahaso as I said np and code happily!! :D

Yes, it's clearer. In that case I'd create a subclass of QComboBox with a property that would return content of data.

@roseicollis To avoid "Configuration unchanged" just rebuild your project

That was my point. Your sample program that was posted won't compile so it is not possible to see the problem with your compiled version (it must be different). You can only manipulate the instance of a class/structure/object. You cannot call any (non-static) members of QLabel directly. I would be surprised if this example doesn't work: #include<QLabel> int main(int argc,char* argv[]) { QApplication app(argc,argv); QLabel *label=new QLabel; label->setText("Hello world"); label->show(); return app.exec(); }

I finally got to solve this by myself. I only had to add 'libqgfxtransformed.so' to my target's /usr/lib/qtopia/plugins/gfxdrivers folder. I then ran my app using the '-qws -display transformed:rot90' switch and I got my rotation done!