MainWindow+Dialogs

[fruzzo]

Hi, I've a QMainWindow with inside its layout a menu of pusbuttons and a groupbox. The behaviou of my gui is this one:
- when a click on a push button of the menu I want open something like a dialog inside the area of a groupbox without create a new window for the dialog.
Is possible to do this?
For the moment instead of creating a real qdialog, a create a custom qwidget and it work:
myWidget * pMyWidget = newMyWidget();
myGroupBoxLayout->addWidget(pMyWidget );
However I have a problem of management (I think it's too hard) with this idea in the case of cascade calling of this sort of "dialogs":
MainWidow open MyWidget1, clicking on a button of this one it open MyWidget2 (always inside the area of the groupbox), clicking on a button of this one it open MyWidget3 always inside the area of the groupbox). Closing MyWidget3 must reappear MyWidget2, and closing MyWidget2 must reappear MyWidget1.
Any idea to solve this task?