MapForums

Sorry for the duplicate post - didn't find this forum until now.

I have been developing an Add-In for MP2004 using VB6 SP6. Most of the functionality in the Add-In is computational so I develop mostly in a helper application so that I can debug the development. Every now and then, I integrate the code from the helper to the Add-In and verify the functionality in the Add-In.
Everything was going well until a day ago when I received an 'object not set' error. The error appears only in the Add-In - not in the helper application. I commented out the offending code and the error appeared again only a few lines above the commented out code. Since I can't debug in MapPoint, I wanted to post in the forum for advice, similar experience, and help.

Thanks,

Joe

I work in both VB6 and C#.

With the advent of .Net and some rather recent patches called
(something like) "COM-Killers," I've noticed a few things:

- It appears that all VB6 calls are routed through .Net (invoke)
- VB6 seems to have a governor on it's speed (to frustrate any late adopters). C# is as fast as VB6 used to be.
- There are random errors that never happened before these "patches."

"VB6 doesn't handle COM correctly" was what I was told.
Right! - not anymore, it doesn't!

Mike Mattys

Heh, Speaking of sour ...

For the record, I'm beginning to like Visual Studio 2008 very much.
Add to that SQL Server Express and the rest of the Microsoft lineup ...
Once the rock gets rolling again it's going to be a blast!

Sorry 'bout the hijacking, back to the task at hand:

One thing I did was to put a label AtTheTop and then a trap (on error resume next/if err.number>0 then goto Trap) where I reinstantiated everything and then Resume AtTheTop.


Mike Mattys
Mattys Consulting - Custom Programming

Thanks for the response!

Wow! I think my laptop received a couple of patches recently. I almost feel watched.

So, a couple of follow up questions:

1. Can I use VS 2008 to develop the Add-In and call it through a CCW in MP2004?
2. What version(s) of MapPoint support .Net?
3. I like the solution in the last post but I was wondering if you have experienced a race condition with it?

Hi Joe,

1) Yes
2) MapPoint can't really tell the difference between programming environments unless, of course, you're using
3) Let's see, MapPoint is single threaded and this is a COM Addin ... hm ... nope, I don't think so.

Mike Mattys
Mattys Consulting - Custom Programming

Just in case:
See this thread: VB6 Mutex? Need to Eliminate Race Conditions - VBForums
Look for code called cFileLock.

(Not sure what you're application is)

Mike Mattys

Thanks for the quick reply!

My application is weather balloon tracking. The Add-In provides the computations to predict a flight path (and display it on the map), simulation a balloon flight (and display it on the map), and track a balloon in real-time (and, well, you know).

Race may have been a poor word choice on my part. From the posted solution, the Add-In would resume execution, and start over (that might be simplifying it). If the error continues, then it resumes and starts over again. It seemed like a possible scenario so I asked about it.
I'm curious about VS 2008 and the CCW. Would that combination get around the 'features' in the patches? My thought is MP2004 might have issues using COM as well and I would be no farther ahead. On the other hand, if it is stable, then I have a solution for multiple versions of MapPoint.

Thanks,

Joe

I'm not sure what this COM Callable Wrapper thingie is.

All we did was copy the registry keys that were made for other Office Addins under our own MapPoint Key and the Addin showed up with right-click-Install of the setup component.

Nothing to do with VB6, though - can't get around it being non-multithread and non-Unicode (unless you want to pay somebody $800 for it).

Mike Mattys

Thanks!

If I may ask, what level of VS2008 are you using? Express? Standard? Professional?

Joe

Hi Joe,

I jumped right into purchasing the Pro version to participate in
a SCRUM run with several developers from dba MainPage
to produce Northwind.NET - Home.

Thereafter, my brother, Eric, and I began experimenting with different
ideas using ADO, SAP, SQLS, MapPoint, Access, etc.

Mike Mattys
Mattys Consulting - Custom Programming