Comments on: LabVIEW Object-Oriented Programming Introductory Walktrough

By: Eugen Graf

Eugen Graf — Mon, 07 Apr 2008 21:53:14 +0000

Nice video Tomi!

That was my first step in learning LVOOP.
One question
Why did you give the red color as default in the “get color.vi”? It`s your favourite color?

Thank you, Eugen

By: Pierre

Pierre — Sun, 18 Nov 2007 17:24:30 +0000

Tomi have you ever had a reflexion about memory management of a VOOP class system.

I am using objects in very large application (more than 3000) and I have to manage frames, events, pictures, acquisition processes and very large data (up to 500M). I am actualy using dqGOOP for this. I use my own inheritance system.

Can VOOP be more efficient for memory management.

Thanks for all your reflexions, I have read many of them.

Pierre Delvart

By: Marcus14

Marcus14 — Sun, 07 Oct 2007 17:40:40 +0000

Excellent video to begin to understand LVOOP

By: Tomi Maila

Tomi Maila — Tue, 07 Aug 2007 06:00:48 +0000

Anthony, actually functional globals and LabVIEW classes are not alternative implementations in the use case you explained. LabVIEW objects, i.e. class instances, flow on the wire in a similar way as any other LabVIEW does. However unlike any other LabVIEW datatype, object data is hidden from the user and cannot be accessed by any other means than using method VIs. Hence the creation of method VIS. Functional globals on the other hand are globals the the method call accesses the same data everywhere.

By: Anthony Lukindo

Anthony Lukindo — Mon, 06 Aug 2007 23:43:44 +0000

Hi Tomi:

OK let me try again

The video intro of doing LV classes that you posted shows how to encapsulate the vehicle ‘color’ data and then expose an interface to write-to and read-from the LVClass.

For someone who uses Function Globals, this same functionality could be implemented using the Functional Global. So the question arises regarding the advantages of doing this via the LVClass rather than the functional global. I feel that there is a lot to benefit from learning the pros and cons when comparing these two specific two methods.

I hope this clarifies the question

Thanks

By: Tomi Maila

Tomi Maila — Mon, 06 Aug 2007 06:05:09 +0000

Anthony, I’m afraid I didn’t quite understand what you are after with your question. Classes can contain methods with uninitialized shift registers, so these two methods don’t seem complementary to me. Would you clarify the use case you were thinking of.

By: Anthony Lukindo

Anthony Lukindo — Mon, 06 Aug 2007 04:18:23 +0000

Hi Tomi:

This is a good introduction. As they say: A picture is worth 1000 words!

One question is when does one choose to go with the ‘Class Architecture’ rather than a ‘Functional Global’ (i.e: the one with uninitialized shift registers).

Your advice is appreciated

Thanks

Anthony

By: Tomi Maila

Tomi Maila — Fri, 27 Jul 2007 09:36:01 +0000

Carsten, have you informed NI about all the building related issues. I’ve myself reported to NI dozens of LVOOP related issues and many of these issues were already fixed in LV 8.2.1 and some will be fixed in future versions of LabVIEW. So it’s benefitical to let NI to know about LVOOP related issues as early as possible.

LVOOP is a new feature and not everything is working properly or optimally designed. The more we give feedback to NI, the better product we can expect to have in our hands in the coming years.

By: Carsten

Carsten — Fri, 27 Jul 2007 07:05:24 +0000

It’s better compared to typedefs that you’ve got encapsulation and that you can style the wires. Also the handling in the project manager is IMO better using classes.

But it’s worse if you want to build applications. This doesn’t work correctly sometimes because for classes unused typedefs etc. shouldn’t be removed. Unfortunately for large projects this is not feasible. Here NI definitely forgot to adjust the application builder to consider classes correctly…

By: Tomi Maila

Tomi Maila — Tue, 24 Jul 2007 13:06:05 +0000

Alvin, such a video may be coming later on. Meanwhile you should take a look at articles in the Introduction to OOP in LabVIEW category.