LabVIEW Idea Exchange

When entering debug mode (turn execution highlight on) it can be hard to see what is happening.

With event structures it can be hard, but there are subtile changes. Sometimes it's impossible. For instance, if you run this VI, and wait a while, it is impossible to why the VI has not stopped. In this case it's easy to deduce, but it can be really hard. Probes also don't provide a solution here...

SubVI's get a green arrow when they are executing. So, could structures get them as well?

Some very useful properties for UI manipulation on graphs and charts do not exist. This makes it impossible to make very dynamic UI's with variable number of plots or dynamic resizing in panels.

It is possible to set Legend.number of plots and Legend position. It is not possible to set:

Graph palette, scale legend or cursor legend position. This makes resizing graphs very limiting.   

Further, it is possible to programmatically create a custom legend.  However it is not possible with cursors because there is no property available to get the current cursor values. Please can we have cursor.values[] and cursor.legend.number of rows

(This is an idea related to Jack's idea here, which however deals with "reshape array".)

When using "built array" with parts that are mismatched in lenght, the largest input wins and the rest are padded with the default value for the given datatype (zero for numerics). This is often not desirable, for example when graphing multiple plots.

Padding with zero causes extra data (zeroes) to show on the graph that did not exist in the original wires. A more desirable option here would be to pad with NaN so only actual data is graphed.

My suggestion is to add an optional input to "built array" that allows defining the pad value is case the inputs are mismatched.

Here is an example how it could look like. (of course the icon would probably need to change a little)

This has been discussed in various places like here, but I couldn't find an idea for it...

There are quite a few LabVIEW primitives which will always run, even if presented with an error on the "error in" terminal. Common examples are "Close Reference" and "Close File". 

What would be really useful is to have some kind of visual indication of this behaviour. Ideally this would be a simple marking on the VI icon which could be easily replicated by LV users when we create such VIs ourselves. (It could possibly even be an option in the icon editor!)

Currently the only indication that a VI will run on error is this discrete line in the VI help:

I believe a visual indicator would be much more fitting for LabVIEW as a visual language, and would make this behaviour far more obvious to LabVIEW users.

Working with class method VIs becomes easily confusing if you need to use VIs from several classes that are inherited from each other. Every class adds or overwrites VIs from one of the ancestor classes but usually you don't know which one. And if you're just user and not developer of this class structure you're usually also not interested in the exact inheritance hierarchy.

Look at the picture: As programmer of the application "main.vi" I'm just interested in Class 3 but I also need to know the internals of Class 1 and Class 2 whereby Class 1 is not even in my project. So I can't see that there are also other cool methods within Class 1 and to get methods from Class 2 I also have to search inside of it and compare against Class 3.

As reference: This is the content of Class 1

What I suggest and expect is the following:

=> The class tree shows all available methods within each single class!

bright colors: Methods that are defined in this class; pale colors: inherited methods

Currently, you can place a probe on a wire while developing, which is an indicator of the data on a wire. I want the ability to CONTROL the data on the wire, with a data forcing mechanism.

The implementation would be very simple... right click on a wire, and in the context menu the option "Force" would be right under "Probe." It would pop up a window of the forcing control, and while the VI is running and forcing is set to "Enable", the programmer can control the values that pass on the wire. If the force window were set to "Disable", the data in the wire would be completely controlled by the VI's logic.

I think the implementation by NI could be trivially simple. If you only allow a forcing control to be added during edit mode (not while the VI is running), the force could be added as an inline VI (as denoted by the green rectangle on the wire). The code inside the inline VI would be as follows, and the front panel would be "Data Force (1)" as shown above.

Of course, if you could add a force to a wire during runtime like probes, props NI. But I would be PERFECTLY happy if you could only add these force controls in edit mode prior to running.

One level further (and this would be AMAZING, NI, AMAZING): enable and disable certain parts of the cluster that you would like to force and allow the other elements to be controlled by the VI logic. I made the example above because it would be very natural to ONLY force Sensor1 and Sensor2, and letting the output run it's course from your forced input.

tl;dr  There's a summary at the bottom if this is too long for you.

Quick Drop is pretty useful when it comes to dropping things and the fact that it also gets items from the project is great.

What I don't like about QD, however, is the keyboard shortcuts. These allow you to perform custom actions in LV and the concept itself is great, but the implementation QD uses has some issues which other similar tools like the right-click framework and LabVIEW Speak don't have, such as the items in the following list.

The problems:

• It requires you to remember keyboard combos to call the plugins. That's great as a secondary access mechanism, but is terrible as a main one for a few reasons:
1. It is not discoverable.
2. It requires you to remember key combos.
3. It doesn't work if you want a longer list of macros which perform all kinds of useful operations, because you run out of available shortcuts.
4. Likewise, you have shortcut collisions, because people want to use the same shortcut for different plugins, so you might say "Ctrl+T", and it will mean something else to the person you're talking to.
• Setting options on the plugins is done by pressing the Shift key or other similar magic combos instead of having a clear representation in the user interface.

So, what can we do about it?

I think a good first step would be to stop thinking of these as "keyboard shortcuts". They should be thought of as custom actions or macros and they should simply appear in the list
along with the regular items, like so:

There are a few things to point out in this image:

• The actions appear in the list using their full names and they have a glyph to set them apart from the other items.
• The actions may (or may not) have a shortcut.
• The actions may (or may not) have a keyboard shortcut (and there's no reason in principle why regular items can't have them too). This solves the existing problem of the shortcut limit - you only assign shortcuts to actions you access regularly, just like you can already do today with menu items.
• There's a ring on the bottom which shows just the items, just the actions, or both. Ideally, the value of this ring would also be settable by other means (e.g. open QD using Ctrl+Shift+Space and the list only shows the actions or open QD when you have a selection and the list only shows the actions).

OK, so that's step one and it solves the first issue - the actions are discoverable, accessible and not limited in number.

Now step two - some of you may have noticed that the image has another new thing - there's an expand button on the right side.
Clicking that button will open this panel:

This area shows the details of the currently selected action and allows selecting options for it.

Here's what we see in this example:

• A title.
• A description.
• An image.
• In the settings area, I gave the "Build array of references" action an option - you can choose to align the Build Array node to the center, the top or the bottom of the references.

The panel should remember its last open setting between calls and when it's open, it should work asynchronously, so that it doesn't delay the operation of QD.
For the VIs which appear in the panel, there should be a standard template for loading and saving values, for showing titles and help data and for shutting down. If the VI fails to respond to the shutdown command within N ms, Quick Drop should proceed and not wait for it.

Of course, once we have this panel, the next logical step is to also have it show the help for standard items, similar to this idea:

So, to sum up:

1. Custom actions should be in the list of Quick Drop items.
2. Shortcuts for actions and items should be fully customizable. That means that you can still use keyboard shortcuts to call the actions, just like today.
   
3. There should be a panel which allows customizing options for actions and show the help for regular items.

I am struggling with my Event Structure event list and the corresponding list of cases in the parallel consumer loop Case Structure.

Both have currently over 100 cases each and finding one or scrolling down to access the latest one has become painful due to the lack of a scrollbar in these lists.

For instance, here is the Event Structure list:

Same goes for the list of controls in a Local Variable (and other objects, I am sure).

There is no reason why such lists do not have a vertical scrollbar when that corresponding to a Enum do have a scrollbar:

Or is there?

Suggestion: All long pulldown lists should have a vertical scrollbar

It has come up here in a different discussion, but I think it should be a separate idea, so here it is!

If we disable part of the code using the diagram disable structure, the disabled code gets lighter in color. The new compiler is good at eliminating dead code (i.e. things that don't need to be computed because there is no output), so it could be useful if these code parts are also bleached in a similar way to indicate that fact.

Here's how it could look like.

I would even suggest this to be enabled by default. Of course there also needs to be an option to turn it off....

(I was about to write up this idea, but then, searching for "dead code", I found comment by SynchronizationOverhead. So the original credit goes there, of course ;))

So when it comes to using a queue, there is a somewhat common design pattern used by NI examples, which makes a producer consumer loop, where the consumer uses a dequeue function with a timeout of -1.  This means the function will wait forever until an event comes in.  But a neat feature of this function is it also returns when the queue reference becomes invalid, which can happen if the queue reference is closed, or if the VI that created that reference stops running.

This idea is to have similar functionality when it comes to user events.  I have a common design pattern with a publisher subscriber design where a user event is created and multiple loops register for it.  If for some reason the main VI stops, that reference becomes invalid but my other asynchronous loops will continue running.  In the past I've added a timeout case, where I check to see if the user event is still valid once every 5 seconds or so, and if it isn't then I go through my shutdown process.

What I am thinking is that there could be another event to register for, which gets generated when that user event which is registered for, becomes invalid so that polling for the validity of the user event isn't necessary.

before:

after: