How do I quickly update the ActiveX automation references in my VIs when the ActiveX interface changes?

Question

Hello all,
I joined a test automation team in the middle of a large project and
inherited a huge set of VIs (over 700) and associated architecture for
this automation (not to mention the several thousand TestStand
sequences).  Another part of the project is being developed by our
customer, who is using VB 6.0 to create ActiveX components which we
need to use in LabView to access their hardware.  They've already
invested a large amount of time developing these ActiveX components,
and they are not finished -- meaning the ActiveX interfaces will be
changing.  Every time they send updated ActiveX components, I have to
re-write many, many VIs including updating a couple strict typdefs. 
This process takes way too much time and is mind-numbing and prone to
error or omission.
Unfortunately I can't post any of the VIs because of a NDA.  But
perhaps a bit more detailed explanation would help.  TestStand calls a
VI to open and get an ActiveX reference for automation (which it stores
in a variant).  It will pass this reference into any VI it calls to
perform specific functions through this ActiveX interface.  For
example, one VI that may be called passes this automation refnum into
another, which passes it to another, which passes it into another to
get the actual ActiveX reference stored in that variant (through a
Variant To Data call with a strict typedef of the ActiveX component
wired to the type input).  [See the attached image of this sample VI
hierarchy: the far left icon would represent TestStand, and the far
right is the strict typedef.]  Any of the VIs in the chain might use
ActiveX Property or Invoke nodes, and it can break at any one of those
when the ActiveX component changes.  It's easy to fix each one, but
since there are so many VIs it takes a very long time.
Is there any way at all to do a massive search/replace or something to
make the ActiveX references update?  I realise that even though
property or method names stay the same from one version to the next,
they are different references.  Is there a way to update these based on
name if you give it the base ActiveX reference?
Thanks in advance for any help!
Tom Williams
Attachments:
hierarchy.GIF ‏6 KB

Answer 1

Ben,
Unfortunately I can't post any VIs that would demonstrate the problem
because the ActiveX components are confidential.  I'll try to develop
my own ActiveX dll that will demonstrate it, but in the meantime, in
hopes that another picture will help, I've attached an image of a block
diagram (with some names changed to protect confidential information)
of one of the lower level VIs from the hierarchy I posted.  In this
example, the "Automation Refnum IN" is an input with a type definition
linked to the strict typedef based on the ActiveX automation dll that
has changed.  I updated that typedef, but as you can see the output to
the "Class1" indicator is broken.  If I delete the "Class1" indicator
and select Create->Indicator from the Class1 property node, and then
wire the new "Class1" indicator to the connector pane, the VI is fixed
-- at least at compile time.  In most cases there is also a runtime
problem where the reference obtained by one of the intermediate
property nodes is null, so the property or method node that uses it
fails (e.g. "_VNManager.Networks" property returned is 0, so the
"_Networks.Network1" property node fails).  To fix this problem, I have
to delete the wires between the property nodes, and one by one select a
different property/method, then select the correct property/method and
re-wire.  There seems to be a bit of "jiggling the handle" to get it to
work though.
I don't know if the ActiveX developer changed anything in this class,
but if he did, he didn't change the name of this class.  I would like
to have to modify the VI only if a class, property or method has
changed name or been removed.
Does that all make sense?  Thanks for any pointers or help!
Tom
Attachments:
Class1_Path.GIF ‏7 KB