[Qt-interest] How to get a widget's ownership and show it in another widget?

[Kermit Mei]

Hello, I want to implement a MainWindow Widget which is inherited from
QWidget. And I need a mothed MainWindow::setCentralWidget(QWidget
*widget) which works like QMainWindow::setCentralWidget(...) do.

I can't us QMainWindow's method, because I need some more adjust.And I 
can not use QStackWidget, too. 

Can anyone help me tell me how to do it?

BTW: How can I hide a QMainWindow's Title bar?

Thanks!
Kermit