I've been using the OOP features of LabVIEW for various projects lately and one thing that I struggle with is a clean method to save and recall objects. Most of my design schemes have consisted of a commanding objects which holds a collection of worker objects. Its a pretty simple model, but seems to work for some design problems. The commander and my interface talk to each other and the commander sends orders to his minions in order to get things done. For example, one parrent class might be called "Data Device Collection" and it has a property that is an array of "Data Device" objects. The Data Device object is a parent class and its children consist of various data devices such as "DAQmx Device", "O-Scope Device", "RS-232 Device", etc. When it comes to saving and loading data, the commanding class's "Save" or "Load" routine is called and at that time all of the minions' settings are saved or recalled from disk. My save routine is more-or-less straight forward, although it still requires an overwriting "Save" and "Load" vi. Here is an example: It isn't too bad in that it is pretty straight forward and simple and there also would be no changes to this if the data structure of the class changed at all. It also can save more generalized settings from it's parrent's class which is also a good feature. What I don't like is that it looks essentially the same for each child class, but I'm at a loss on an effective way to move the handling of the save routing into the parent class. The load routine is more problematic for me. Here is an example: Again, the desirability of moving this into the parent class would be awesome. But the biggest complaint here is that I can't maintain my dynamic dispatch input-output requirements because the object that I load is strictly typed. Instead I have to rely on reading the information from the loaded object and then writing that information to the object that exists on the dynamic dispatch wire. I also dislike that unlike my Save Routine, I will need to modify this VI if my data structure of my object changes. Anyway, any input and insight would be great. I'm really tired of writing these same VIs over-and-over-and-over again, and am after a better way to take care of this in the parent class by keeping the code generalized but still maintain the ability to bring back the saved parameters of each of the children classes. Thanks for your time.

LabVIEW

Best practice for saving and recalling objects from disk?

Author

I'm still trying to find a better solution for this.

The best solution (IMO) would be if my classes inherited the save and load routines from a parent "Saveable Objects" class that did not require overriding the "Save" and "Load" VIs, but they just "work".

Hmmm.....

Message 11 of 11

(494 Views)

What do you need our team of experts to assist you with?

Request a quote Find the right product Place an order Get support on a product

How can we help?

Please enter your information below and we'll be intouch soon.

This field is required

Preferred communication method

Email Phone call

What do you need our team of experts to assist you with?

Request a quote Find the right product Place an order Get support on a product

LabVIEW

Best practice for saving and recalling objects from disk?

Re: Best practice for saving and recalling objects from disk?