Win32: ByRef equivalent in pythoncom for function callbacks?

[Mike Fletcher]

I've been trying to get an IE WebBrowser control to report OnScroll events
to my (wxPython wxWindow) class.  I've got the control created, and I can
catch the WebBrowser events as expected.  However, I can't seem to convince
the COM system that my callback is usable.

Here's what I'm trying (added to wxPython's IE demo):

	def OnDownloadComplete(self ):
		print 'download complete'
		try:
			class CallbackRedirect:
				def __init__(self, object ):
					self.object = object
				def __call__( self, *args, **namedargs ):
					return apply( self.object, args,
namedargs )
			self.ie.Document.documentElement.attachEvent(
"onscroll", CallbackRedirect( self.OnScroll) )

download complete
Traceback (innermost last):
  File "P:\portals\tests\iedemo.py", line 155, in OnDownloadComplete
    self.ie.Document.documentElement.attachEvent( "onscroll",
CallbackRedirect(
self.OnScroll) )
  File "<COMObject <unknown>>", line 2, in attachEvent
TypeError: The Python instance can not be converted to a COM object


Not really sure how to do this.  The VB docs say to use ByRef( methodname)
to pass the argument, but I don't see a similar macro anywhere in the python
code.  Just using the raw function gives:

download complete
Traceback (innermost last):
  File "P:\portals\tests\iedemo.py", line 159, in OnDownloadComplete
    self.ie.Document.documentElement.attachEvent( "onscroll", self.OnScroll
)
  File "<COMObject <unknown>>", line 2, in attachEvent
ValueError: argument is not a COM object

Does pythoncom have some convention for creating callback objects to which
I'm not adhering?

Thoughts and suggestions welcome,
Mike
__________________________________
 Mike C. Fletcher
 Designer, VR Plumber
 http://members.home.com/mcfletch