#include <QtCore>
#include <QtGui>

int main(int argc, char** argv)
{
    QApplication app(argc, argv);
    QMainWindow mw;
    QScrollArea sa(&mw);
    sa.setStyleSheet("border: 1px solid; border-radius: 7px;");
    sa.adjustSize();
    mw.showMaximized();
    return app.exec();
}