python and COM

[Brian Blais]

Hello,

I am trying to communicate to a Reuters feed using Python, using a particular set of
libraries called the Adfin Real Time library. I have VB code, and am trying to port
it to python, and admit I really do not understand COM objects and being a Linux guy
mainly, I don't use VB at all. I've had some marginal success, but am coming up
empty when it comes to setting up callbacks.

For example, this works:

import win32com.client
import time

symb='GOOG.O'

mylist=win32com.client.Dispatch('AdfinXRTLib.AdxRtList')

mylist.Source="IDN_RDF"
mylist.RegisterItems(symb,"ASK")
mylist.StartUpdates(4) # Mode Image

while mylist.ItemStatus(symb):
pass

for i in range(100):
m=mylist.Value(symb,"ASK")
print m
time.sleep(2)


but to get it to automatically updated quotes, in VB they do something like

#================
Public Class Form1
# Dimension a Public Real Time list object that is capable of handling events
# note from me: not sure what this line does really
Dim WithEvents AdxList As New AdfinXRTLib.AdxRTList

Public Sub AdxList_OnUpdate( <some args deleted>) Handles AdxList.OnUpdate

do stuff with the updated data

End Sub

Private Sub Button1_Click(<some args deleted>)

do stuff with button click
End Sub
End Class
#================

It seems as if the important part is the "Handles AdxList.OnUpdate", which I assume
is basically saying "call me when AdxList.OnUpdate is called". I have no idea how to
get this to point to a python function, so I can make the AdxList.OnUpdate call
python code.

Is there a tutorial somewhere about this stuff, or is there a proper place to ask
such questions?


thanks,


Brian Blais

 

[kyosohma]

Hello,

I am trying to communicate to a Reuters feed using Python, using a particular set of
libraries called the Adfin Real Time library. I have VB code, and am trying to port
it to python, and admit I really do not understand COM objects and being a Linux guy
mainly, I don't use VB at all. I've had some marginal success, but am coming up
empty when it comes to setting up callbacks.

For example, this works:

import win32com.client
import time

symb='GOOG.O'

mylist=win32com.client.Dispatch('AdfinXRTLib.AdxRtList')

mylist.Source="IDN_RDF"
mylist.RegisterItems(symb,"ASK")
mylist.StartUpdates(4) # Mode Image

while mylist.ItemStatus(symb):
pass

for i in range(100):
m=mylist.Value(symb,"ASK")
print m
time.sleep(2)

but to get it to automatically updated quotes, in VB they do something like

#================
Public Class Form1
# Dimension a Public Real Time list object that is capable of handling events
# note from me: not sure what this line does really
Dim WithEvents AdxList As New AdfinXRTLib.AdxRTList

Public Sub AdxList_OnUpdate( <some args deleted>) Handles AdxList.OnUpdate

do stuff with the updated data

End Sub

Private Sub Button1_Click(<some args deleted>)

do stuff with button click
End Sub
End Class
#================

It seems as if the important part is the "Handles AdxList.OnUpdate", which I assume
is basically saying "call me when AdxList.OnUpdate is called". I have no idea how to
get this to point to a python function, so I can make the AdxList.OnUpdate call
python code.

Is there a tutorial somewhere about this stuff, or is there a proper place to ask
such questions?

thanks,

Brian Blais

--

I found some info on Python, VB, and COM. Check out the links below:

http://vb2py.sourceforge.net/
http://mail.python.org/pipermail/python-list/2005-July/332502.html
http://www.oreilly.com/catalog/pythonwin32/chapter/ch12.html
http://mail.python.org/pipermail/melbourne-pug/2006-April/000132.html

Not sure if those will help, but they might give you some food for
thought.

Mike

 

[Larry Bates]

Hello,

I am trying to communicate to a Reuters feed using Python, using a
particular set of libraries called the Adfin Real Time library. I have
VB code, and am trying to port it to python, and admit I really do not
understand COM objects and being a Linux guy mainly, I don't use VB at
all. I've had some marginal success, but am coming up empty when it
comes to setting up callbacks.

For example, this works:

import win32com.client
import time

symb='GOOG.O'

mylist=win32com.client.Dispatch('AdfinXRTLib.AdxRtList')

mylist.Source="IDN_RDF"
mylist.RegisterItems(symb,"ASK")
mylist.StartUpdates(4) # Mode Image

while mylist.ItemStatus(symb):
pass

for i in range(100):
m=mylist.Value(symb,"ASK")
print m
time.sleep(2)


but to get it to automatically updated quotes, in VB they do something like

#================
Public Class Form1
# Dimension a Public Real Time list object that is capable of handling
events
# note from me: not sure what this line does really
Dim WithEvents AdxList As New AdfinXRTLib.AdxRTList

Public Sub AdxList_OnUpdate( <some args deleted>) Handles
AdxList.OnUpdate

do stuff with the updated data

End Sub

Private Sub Button1_Click(<some args deleted>)

do stuff with button click
End Sub
End Class
#================

It seems as if the important part is the "Handles AdxList.OnUpdate",
which I assume is basically saying "call me when AdxList.OnUpdate is
called". I have no idea how to get this to point to a python function,
so I can make the AdxList.OnUpdate call python code.

Is there a tutorial somewhere about this stuff, or is there a proper
place to ask such questions?


thanks,


Brian Blais

It looks like you are correct. This is a callback function that gets
called when the update occurs. The only coverage of this I've found is
in "Python Programming on Win32" but it is rather brief even there. I
have not any event driven callbacks, so I can't help all that much.
Normally you define a Python class that has methods that ADxList.OnUpdate
is expecting to be able to call. Then depending on implementation you
either call it with an instance of that class or you may have to wrap
the instance in a COM IDispatch object by calling win32com.server.util.wrap()
around an instance of the function. Sorry I can't be more helpful.

-Larry