I currently have a project that I am refactoring. There is a lot of coupling that is not sitting well with me due to typedefs belonging to a class, then getting bundled into another class which is then fired off as event data.
Effectively, I have class A with a public typedef, then class B contains ClassA.typedef and then class B gets fired off in an event to class C to be handled. Class C now has a dependency on class A which is causing a lot of coupling I don't want.
For my real world example I query a bunch of data from our MES, which results in a bunch of typedef controls on the connector panes of those VIs. Those typedefs belong to the MES class. I then want to bundle all that data into a TestConfig class and send that via an event to our Tester class. But, now our tester has a dependency on the MES.
I see a few ways to handle this. First is move the typedefs currently in the MES class, to the TestConfig class. The MES VIs will now have the typedefs from the TestConfig class on their connector panes, but at least the dependency is the correct "direction." Or, I can move the typedefs out of classes all together, but then I am not sure the best way to organize them. Looking for how others have handled these sorts of dependencies.
View File XNode Editor
8 Years ago the first version of the XNode Manager was posted to the code repository in an attempt to allow the editing of XNodes. Being a fan of XNodes, but knowing that the XNode Manager is pretty limiting because of its age, I set out to make a new version with similar functionality.
The XNode Manager had a blank XNode, and blank Abilities that it just made copies of. This is fine but then the abilities and XNode are quite old. There were many new Abilities added since version 8.2 and you can't add them using the XNode Manager. My XNode Editor reads your LabVIEW resource and populates the list of abilities to create from the ones that are possible to create. Then VI server is used to create the XNode, State control, and Abilities. This sets up the connector pane like it should and should work with all future versions of LabVIEW, until NI changes something that breaks it. It also reads in the XNode Ability descriptions to help understand how to use the new ability VIs.
In addition to being able to create and edit XNodes, you also can edit the XNode icon, and description, along with adding any new abilities.
Be aware this uses several private functions, and several undocumented features that could be potentially bad. I did a decent test to make sure memory leaks weren't a problem and I made several XNodes and Abilities and it seems stable. But at the end of the day if it blows up and crashes, don't be surprised, you've been warned. The original thread with discussion and progress on this tool was started here.
Submitter hooovahh Submitted 03/15/2017 Category XNodes LabVIEW Version
After working on the set cluster element by name xnode, it made me realize i could use the same concept to convert a variant array to a cluster. The technique is actually pretty simple, the xnode generates a case structure for each element in a cluster in cluster order, wherein a bundle by name is used to set the value and an unbundle by name is used to get the type, a variant to data is used to convert the data. This has some benefits over some methods, you are not limited to 255 elements, although that is not usually the case some of us are paranoid that clusterosaurus giganticous will be larger than expected. It also has a draw back that is that when converting from a variant array all the elements must have unique, non-blank names, and this is usually the case.
I think this technique (though very brute-force) might be useful for some other things let me know what you guys think.
This Xnode allows setting a cluster element by label string without using references. I pulled a great deal of inspiration from Hooovahhs Variant Array to cluster xnode, which i suppose this could be used for, another benefit is its not limited to 255 elements. Its mostly experimental because I haven't used it much.
I've been working a lot lately with by-reference architectures that still cooperate completely with LabVIEW's implementation of OOP and polymorphism. I've also recently taken an interest in trying to speed up development with secondary providers (similar to GOOP) to enable automatic creation of accessor VIs hidden behind the DVR, automatic creation of the private data type and constructor/destructor, etc. within the project window. I'm generally not a fan of the extra stuff that goop adds in to classes, I'd prefer to keep the source code looking as close to a normal class as possible.
That said, I've started on my first ever XNode and it's a cross between an unbundle by name node and the -> operator in C. It functions just like a normal UBN, however it was also pull items out of DVRs. Having to plop down a UBN to pull out the reference from the class, an in place node to dereference, and then another UBN to pull the data out gets tiresome after about the 100th property VI gets written.
So far I've gotten the node drawing completed (except for data type coloring of the labels), the type inferencing from the input wire, and the popup menu for selecting an item. Next up will be the menu selection code so that the names will finally show up in the terminals! Then I get the daunting task of scripting up the GenerateCode ability >_>
Anyone interested in something like this? Following this will be a match to the Bundle by Name node that serves the same purpose except to write the items.