Scroll Area problem

[Lodhart]

Hi, i have a problem with scroll area...

i need some widget with some components and put it all into scroll area. But when i write:

ui->scrollarea->setWidget(QLabel);
and QLabel size is bigger then scroll area, everything works.

when i write:

ui->scrollarea->setWidget(QWidget);
it does not work !.. i can not see scrool bar..

i try: Widget, frame, layout, ... but it works only with QLabel.