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Providing additional Context Help information on Controls that contains information as to their "type" (Classic, System, Silver, etc.) as well as their font, font-size, and control-type (indicator, ring, enum, etc.) would be useful. The utility of this is obvious if you have ever had to modify/update an existing GUI and want to maintain the look and feel when adding new controls -- this would allow you to easily see what was previously used for the existing controls on a GUI. This "verbose" information could possibly be turned on/off as a Tools->Options->Front Panel setting.

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I like compile time type safety checks. I dislike using variants. Occasionally, and increasingly more often, I find myself going to great lengths to provide compile time type safety. At a point, the type check gets lost in the inheritance hierarchy and I am back to depending on runtime checks for errors. It's not uncommon for me to have a class method that needs to "just work" across the bulk of the base types, but it sure is a pain to make wrapper classes, static inlined methods, and a nasty polymorphic .vi to mimic this behavior. Perhaps I am ignorant to some features of LV (do malleable vi's fit in here somewhere?), but multiple dispatch/function overloading sure seems like the silver bullet for this issue without messy inheritance trees.

I'm open to discussion on alternatives. This "problem" has come up in a couple of recent projects of mine, and I always feel dirty using a variant or making a static API for a class that ought to be extensible.

If we type up a list in a text label we can now (since LabVIEW 2023) right-click on it, select quick change and convert it to a number of different objects (array, enum, boolean etc)...Once you have done however, right-clicking on the result does not offer the quick change option anymore.

It would be nice and feel more consistent if the same option was available when right-clicking on the supported objects as well; allowing us to convert those to any of the other options and/or even back to the original list (which would allow you to then edit that list efficiently and then reconvert it). Basically an label/object to object/label quick change, instead of just label to object.

PS. I know there are various quick drop plugins that do parts of this, but this would extend the now in-built function to cover those and more scenarios...

Many times data is generated or transformed using a function or vi with a single output. In those cases the wire name is the one given by the function or VI terminal, but it would far more descriptive if the wire could have a proper name according to is usage in the block diagram. You can attach labels to wires but these are not propagated particularly when used in places like "bundle" or in structures (for, while, etc.). In large diagrams thus it can be difficult sometimes to now what a wire is for.

This idea proposes to enable the override of the default name of the wire connected to output terminal to that of the label of the function, in case the label is not empty, for single output function or VI. In a similar fashion to the propagation of labels of constants. This could be automatic (not empty label) or deliberate (for instance, using a tick box in the properties page)

This is different from idea Allow-Wire-Labels-to-Dictate-Name-Inheritance-in-Bundles in that it follows the current LabView behavior of the wire name being dependent on labels on constants, and avoids possible conflicts.

The Wire Multiple Objects Together QuickDrop tool (Ctrl + W) is extremely useful. However, at the moment it cannot wire a block diagram constant to multiple destinations. It would be useful if it could.

Real-world example

The other day I found myself writing the following code.

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I tried using Ctrl + W to wire the timestamp constant to each of the timestamp global variables. Currently the tool wires the constant to the first global variable only (leaving all other global variables unwired). Therefore I had to manually wire the constant to each of the other global variables, which is a tedious, manual operation.

Side-note: Global variables are used because they are computationally efficient (they can be read and written to very quickly). We needed code that ran in a tight loop (up to 1,200 times per second). The VI above performs the one-off initialisation of the global variables, before they start being read/written to in the loop.

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The database toolkit is limted by the database variant to data function. It can only cast to a labview datatype as long as you wire that datatype to the type input. This means that you have to know the datatype of any SQL query in advance (or convert to string). It would be very useful if the function would also accept a variant datatype. This way it would be possible to cast any complex type into labview datatype, without the need of a predefined cluster.

Image - casting the database input with a the variant type input (circled) doesn't work

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When running NI web server, the domain URL of the server will always redirect to the NI web server (or Systemlink) login page. Every Labview-built web application/webservice has a name and therefore must have a path (like: https://example.com/mywebapp)

I would like to be able to set a default redirect in the NI Web Server configuration to redirect the domain url to the default web application on that server.

It can probably be done in some Apache config file, but those a really managed by the NI web server configuration and are easily corrupted. My forum post about this issue has not yet been answered.

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What is really nice about the database toolkit is that "database SELECT" variant data can be cast directly into an (array of) cluster using the "database variant to data" function.

However, it cannot cast MySQL enums to Labview enums. By default, MySQL returns the enum string, not the underlying integer. As soon as the casting function encounters a string to cast to an enum, it fails to convert all following data.

My not so elegant workarounds:

- cast the enums in SQL and use "database execute SQL" instead of "database SELECT"

- create a view with the enums converted to int.

"database INSERT" does work without hacks: you can use clusters with enums to insert data into MySQL tables. The only caveat there is that LV enums start at zero, whereas MySQL enums start at 1. I work around this by adding an "undefined" value in the Labview enum.

My suggestion is to support enums in the database toolkit. After all, in Labview, it is not hard to convert a string into the matching enum.

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Add a function to Change Directory

"Note" Project Explorer item

TestStand provides the extremely useful Label step type.

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It would be extremely useful if the LabVIEW Project Explorer provided a similar Note project item. The Note would serve as a documentation and annotation tool inside the project. Project notes would serve to explain the purpose of a group of lvlibs or lvclasses, or to provide short descriptions inside an lvlib, lvclass, or virtual folder.

As a workaround I currently use virtual folders to add notes to the project. By convention I name these virtual folders starting with "_Note:". The underscore helps the Note appear first (near the top) when the items are arranged by Name or by Type. By convention I never add any item inside the _Note virtual folders.

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The implementation of a Note item could be quite simple. A Note item would essentially be just like a virtual folder with the following modifications:

Different icon. An icon that resembles a document would make sense.
The Note item would not be able to contain any other items.

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Hi all,

After some issues spending 1 week to get HTTP embedded server working in LV for a single application, I have some remarks that might trigger some need to a more flexible, simple and open HTTP configuration. The current implementation of a HTTP server is quite limited and outdated to my opinion.

First thing is the NI Web Server. This is a nice feature, however, NI recommends using it rather then the outdated Application Web Server but the problem is that this thing is only a single server running on a single port (for every application executable). Good enough for a single web server on a host using a web browser but how about implementing a LV HTTP server for each application (e.g. RPC server)? To my knowledge, every other programming language (e.g. Python, C++, ...) has a core implementation for this.

I have spent a lot of time to see what the best solution is for implementing a HTTP server belonging to a single application executable in LV. This executable is typically a application GUI or a backend service in our projects and we have a lot of them. Every application needs its own RPC server (running on a different port) and hence running its own RPC methods and I ended up implementing a Web Service using a LV Application Web Server, I can't see other ways at this moment using core LV functionality without the need for additional packages to install.

I also miss the enabling and disabling of the HTTP server during runtime. As in our project applications, we also have other transport layers for implementing RPC, such as zeroMQ (thanks to Martijn Jasperse's library on VIPM) and TCP (native built-in to LV). I would like to run only one of these transport services by configuration but here is a second problem here, once the application is running, the HTTP Web Service automatically registers and there is no controlled way for disabling it during runtime, which gives me headaches since I have to change the port number as another transport layer cannot use the same port as the HTTP server. One might say to built another application (actor based) exe and implement the Web Service from there in a different actor but this is a pain in the *** to have 2 exe's for each single application. Why can't the HTTP Web Service not switched OFF and ON again, both in development and runtime? I found a property node to disable the server but it apparently doesn't work (seems related to the native panel web server).

One of the major disadvantages that I also encountered is the HTTP methods that are programmed in a single VI and there is no way to pass data to these method VI's (like using actor framework or even classes in general). It seems we have to use FGV's (Functional Global Variables) to share data between my main application actor and these HTTP method VI's itself. Even then, the HTTP Service Request refnum is only valid in the HTTP method VI itself, once it finished executing, the refnum is flushed and not valid anymore, so no way to pass this refnum using actor framework messages to my application actors. That's quite frustrating since I have to use notifiers within the HTTP method VI's instead as a plan B backup solution signifying that the method VI can proceed and finish its execution once it Wait on Notifier function is complete (since I want to send an answer from my application actors, not from the HTTP method itself)!

Another issue I observed is that I can't "Start" the HTTP Web Service from the right-click menu in the project explorer, it simply crashes with some dubious error that the 'system is currently in an invalid state for the current message'. What does this mean, no clue from NI help docs?

I can only right-click and select "Start (Debug Server)" to make it work (but on the debug port 8001 by default). All other options just fail, the same for "Publish", it simply doesn't work in my LV2020 SP1 (32-bit) version and I have no clue why as there is not a single error message at all!

Also, why must we use MS Silverlight to control application webservers from LV? Silverlight is deprecated and I ended up using MS Edge in "Internet Explorer" mode to get the config page working (after spending another two hours to find out). Even then, some config panes just show up with error dialogs and no way to see active services being registered by the application HTTP web server. In the end I just used TCP View to see active services running. It is always frustrating to use third party apps to do simple things.

As you might notice from this message, I suffered a lot of days to figure out how to implement HTTP in a simple decent way using LV's core HTTP functionality. I wonder if this will be better using LV 2024 Q1?
If anyone has ideas on how to properly configure multiple application HTTP servers for each application on different ports while controlling itself, please share it with me. I am open to any idea's and wonder if there are other solutions for HTTP implementation (not using 3rd party packages). To my opinion, HTTP should be easy and open to configure properly in LV without a lot of current non-working Web Server issues.
Please note that I tried to reinstall the NI Web Server and other web service related stuff using NI package manager but no avail.

Best Regards,

Davy Anthonissen

The current register event callback node is allowing an easy way to handle ActiveX and .Net Framework events. This node is also very similar in appearance to the property nodes, yet it does not have an insert (Add Element) or remove (Remove Element) function available in the context menu. Since the property nodes, and also the named (un)bundle nodes are having this implemented, I think it would be nice to have these easy to access functions instead or having to grow the node, change all the elements below the one that we want to insert and rewire everything.

One downside of this idea is, that it will throw the wires a little further away than the upper mentioned named (un)bundle and property nodes do, since it is a 3 terminal height element.

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In the drivers (DAGmx,NI-Scope/Fgen,...)

If a value (usually as DBL) enters a config vi, it could be coerced by the driver.

That vi should directly output the actual value.

Most often seen in the Forum: A user declares a non valid DAQmx Timing Sampleclock and wonder why the wfrm(data) is not what he expected.

Yes, RTFM help, you can read the properties after configuration but it would easy to add an output to the config vi with the actual (maybe coerced) value. Making the user avare of that 'feature' (instead of popping an error 😉 )

Should not only cover samplerate , other values like FGEN standard funktion parameters (frequency, Phase), actual range, ...

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I like channel wires for obvious reasons. I like to have modules, which work on their own, coming with their own GUI. This is convenient for developing my modules and testing them. Afterwards I want to be free to insert this module into a bigger project, which takes control of my module.

The channel wire controls on the connector pane can be set optional, but LabVIEW throws an error, when executing a VI with not connected channel wire control. (All branches of a channel wire must be connected to a channel endpoint...)
Please make VIs working with not connected, optional channel wire controls on the connector pane. That way, we can have channel wire based modules, which can run on their own, as a single VI, or can be controlled remotely without any change.

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LabVIEW Idea Exchange

Default Setting for "LabVIEW Version" in the Environment

Front Panel Control Context Help: Show Control Type

Multiple dispatch / Function overloading

Label to Object (Quick Change) upgrade to Object/Label to Object/Label

Allow single output function / VI label to override wire name

Mass Compile Should Optionally Override Save Version

Improvement to the QuickDrop Ctrl+W tool: Wire constant to multiple destinations

Add support for [INSTALLDIR] and [DISTROOT] for Packages

dynamic database variant to data with variant type input

Set a default webservice for NI Web Server

database toolkit support for (mysql) enums

Auto-wire cases inside loops when adding shift registers

When right clicking boolean, replace Create > Constant to Create > Create True Constant or Create False Constant

Add a function to Change Directory

"Note" Project Explorer item

HTTP Functionality should be more flexible and open to configuration in LabVIEW

increase the amount of recent files / recent project

Allow inserting and removing event handlers in the Register Event Callback node context menu

In the drivers (DAGmx,NI-Scope/Fgen,...) if a value enters a config vi and it could be coerced, the vi should directly output the coerced value

Optional Channel Wire Control on the Connector Pane