How to cover a gtk popup window?

["Hugh Yao" <hughyao118 gmail com>]

Hi ,all:

   I've got a question:

   I have to show a gtk popup window to show some message.

   And some time I have to show a dialog or a toplevel window after that popup window shown.Then the popup window always on the top of the others,covers the window!

   Well,My question is how can I make the other windows shown in front of the popup window,and covered it?

   thanks a lot!