XRC and dynamically created widgets?

[John Salerno]

Ok, I think I asked this question more generally a few days ago, but now 
that I have some XRC experience, I will be more specific and hopefully 
it will make more sense.

But before I ask, I have one other question. In an example on the 
wxPyWiki I saw this kind of code:

     def InitFrame(self):
1       self.frame = self.res.LoadFrame(None, "MainFrame")
2       self.panel = xrc.XRCCTRL(self.frame, "MainPanel")
3       self.first_arg = xrc.XRCCTRL(self.panel, "FirstArg")
4       self.second_arg = xrc.XRCCTRL(self.panel, "SecondArg")
5       self.result = xrc.XRCCTRL(self.panel, "Result")


Are lines 2-5 necessary for creating the widgets, or are they there just 
so the program will have access to them later? I ran something similar 
myself and it seems like the LoadFrame call automatically creates and 
shows the children of the frame, so I wasn't sure if 2-5 were actually 
doing anything at this point, or if they were just to assign references.

Ok, now my main question: I want to create a program that will allow the 
user to open new tabs using the Notebook widget. I understand how to use 
XRC to design a static layout, but I don't understand where the GUI code 
is supposed to go for the notebook pages that will be created during the 
run of the program. It's not something that I want to appear when the 
program starts, so it seems like it's wrong to put them as children of 
the frame. I thought maybe, since notebook pages are custom Panels, that 
I could put a top-level Panel widget in the XRC file, but I tried this 
and it didn't seem to work. I wasn't sure how to access it, and when the 
program finally ran without errors, it just showed a frame with a panel.

So I hope someone can explain how to use XRC when you expect to create 
new widgets during runtime.

Thanks!