LabVIEW
Save Actor Hierarchy to Configuration File
Just FYI, I've been down the road of trying to just save the whole class to a file, then reloading it later. Unfortunately this *very* rapidly explodes the file size of the config VI and makes it non-human-readable.
The issue is that the classes maintain their version history and include GOBS of stuff about them that's not relevant to your user. Though it's painful, I'd highly recommend writing individual getters and setters for each class's relevant private data.
Are you storing the whole class as a binary blob in the ini file? If so that's probably the issue; you're not just storing your important data, but ALL of the info about the ENTIRE actor, its parents, all of its enqueuers and references, literally everything back up to and including the main Actor.vi.
BTW, as a side tip: one decent way to handle loading and saving private data is to just write a single "Load or Save [parameter]" VI. It will have your class as an input and output, a boolean "Load?" input, a file path input, and an input AND output for the parameter you're getting or setting. If the Load? flag is True, it sets the value from the input to the object. If it's False, it reads it from the object and saves it to the file.
Combine that with creating a malleable version of the "get value from config file" that will automatically set the "Type" (you might can do this with just the polymorphic Autoselect function- it's been a while and I can't remember the specific nuances... maybe the malleable version I made just integrated the Read vs Write into a single config file VI instead of choosing Read or Write in a case structure in the actual reader/writer file).
Anyway, what that gets you is a single place to define the Section and Tag of the item in the config file. It always bothered me that I had the same information duplicated in two spots (namely, the Section and Tag both had to exist in the Reader and Writer). If the layout changed any, you had to update it in both locations or you'd get an error that you wouldn't see until runtime.
@dh10 wrote:
I am not saving the entire class to a binary blob, I am only saving the important configuration setting data.
I am not sure what you mean towards the end of your response. Nothing is duplicated in the configuration file, each section and key show up only once.
The duplication is in the code, no the configuration file. If you have a "Load configuration" VI, you have to tell it the Section and Tag names (for example, "Scale factor") once in the Read and once in the Write. If, later on, you decide to change the name of that tag to "Scale factor (mm/v)", then you have to change it in both the Read VI and the Write VI, leading to potential errors errors with either typos or just plain forgetting to change it in both spots. If "Read" is looking for "Scale factor(mm/V)" and "Write" is looking for "Scale factor (mm/V)" then your code won't work when you try to load non-default values.
Oh, and one other thing- I'm not sure about JSONText, but at least some of the JSON VI's don't actually store default values in the file. For example, if Class.ScaleFactor has a default value of 16, that won't appear in the file. See this thread where I ran into this: https://forums.ni.com/t5/LabVIEW/Flatten-object-to-XML-doesn-t-work-with-default-values-in-class/td-...
