#include <QDebug>
#include <QtGui>

class MyWidget : public QWidget
{
public:

    MyWidget(){}
    virtual ~MyWidget() {}
};

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

    MyWidget widget;
    widget.resize (100, 100);
    widget.show();

    QMessageBox *mb =
            new QMessageBox (QMessageBox::Warning, "Title", "text",
                             QMessageBox::NoButton,
                             NULL, //&widget,
                             Qt::Dialog);
    mb->show();

    return app.exec();
}