[Adobe-source-devel] Disabling buttons

[David C. <unc...@un...>]

I'm trying to understand how the list_box_emulator example works as far 
as disabling the Insert and Delete buttons.

There is a 'can_do_element_operation' in the sheet, and yet it is not 
referenced anywhere. It looks like the buttons are being disabled 
because they are bound to 'insert/delete_params' which both reference 
'selection' which is referenced in the invariant, but I still don't 
quite follow how that works. What exactly is the connection between 
'insert/delete_params' and 'can_do_element_operation'? Is it just the 
fact that 'selection' is in the definition of 
'can_do_element_operation'?

-- 
David Catmull
unc...@un...
http://www.uncommonplace.com/