#include <QtWidgets>
#include <QtGui>

class TWindow : public QMainWindow
{
public:
	TWindow() {}
	void	mousePressEvent(QMouseEvent*)
	{
		Q_ASSERT(! isMaximized());
	}
};

int main(int argc, char** argv)
{
	QApplication app(argc, argv);

	TWindow* w1 = new TWindow;
	w1->showMaximized();

	return app.exec();
}