MVC and DynamicSashWindow

[Danny Shevitz]

I have a question on which I'd like to get persepectives concerning MVC. 
This isn't
strictly a wxPython question, but I'm sure people on this list have dealt 
with it.

I'm using a DSW to display a tree data structure. I already have a MVC 
architecture
implemented, with an Observer/proxy class for my Model that runs underlying 
model
methods and send messages back to the view via pubsub to notify when view 
updates
are required.

My Observer knows nothing about the view, it just post messages which the 
view interprets.
The wrinkle is that when I use a DSW, I don't want all the windows to do 
the same thing. In particular,
I may not want to change the focus in the windows that I am not directly 
editing. Example: I insert a node
in a particular window. Certainly in that window I want the selected item 
to be the new node, but in
the other windows I probably want to keep the focus where it was. The 
problem is that via the mechanism
I am currently using, all windows will get the message to change the focus.

I can think of two ways around this. 1) pass to the Observer the current 
window, so that it knows to send a
different message to that window or 2) put the "select item" code in the 
event handler, and don't delegate
that to the Observer.

The first method seems to violate the separation of concerns in MVC. The 
second seems like it violates
the spirit of MVC since the gui is driving the display state, not the 
underlying model.

Any opinions? I'd love to hear what people do and how they live with 
themselves in good conscience.

thanks,
Danny