LV OOP using accessor (subVIs) or operation bundle/unbundle methods?

Hello

When should I use the (private) (subVIs) accessor methods and when the bundle/unbundle the operation to access the data of the class? What is the reason that the operation bundle/unbundle is introduced in LabVIEW OOP? I need some rules for a codification of the directive.

Thank you

Thanks for your advice. I wanted to understand the differences between a private access vi and unbundle operation as in the picture.

I found a few more explanations on the website: http://www.ni.com/white-paper/3574/en

-> ' Methods 'Read' and 'write' for each data value in a class is a recognized process as being bulky. " LabVIEW 8.5 introduced the ability to create the screw accessor in a dialog Wizard and LV2009 added to other options in this dialog box.

We were concerned about the performance overhead to a Subvi call instead of unbundling just data. We found that our general fees current compiler for the Subvi call is insignificant (measured between 6 and 10 microseconds on average PC). A bundle/unbundle directly on the appellant VI compared to a Subvi is almost the same amount of time. We have a problem with copies of data for unbundled components because a large part of the LabVIEW inplaceness algorithm does not work beyond the limits of the Subvi. To work around the problem, you can also choose to avoid the accessor methods for methods that perform work in the Subvi to avoid returning the Subvi elements, thus avoiding copies of data. This choice is often better OO design anyway, because it avoids exposing the implementation private to a class as part of its public API. In future versions, I bet that this feature of subVIs will become possible, which will eliminate the overhead entirely.

We feel in the long run it is better to improve the experience of the editor and the efficiency of the compiler for these screws rather than introduce data public/protected/community. »

Tags: NI Software

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