Where is the Event Structure?

I am sure this is a stupid question but....
I just upgraded from LabView 6.0 to 6.1. I opened a new vi all excited to try out the new event structure, but I can not find it. It is not in my functions>structures palette. Is there something I am missing?

It seems to me that national instruments was kind enough to provide you with a new splash screen for the four or five hundred you probably had to shell out to get the upgrade.
I'm pretty displeased with the way ni presented that info, since the event structure was really the only reason to upgrade, oh wait that and the "handy" auto selector tool. Which all they should have done is actually explained that if you use tab and spacebar you can switch between the four and two (respectively) most popular tools for either the block diagram or the front panel. For that information is infinitely more useful than the tool, and infinitely less annoying (meaning it actually does what you want it to).

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Some frontpanel controls stop firing the Event Structure

In my main vi,I have an event structure. I created a subVI that also has an event structure. I load the subvi via a subpanel in my main vi. It runs fine for a while. But sometimes after firing events on the subpanel, most but Not All controls on the main VI stop firing the Main Vi's event structure. The Subpanel's subvi event structure always works fine. When I reload the program it works fine again for a while.

This is the problem that's been bothering me too (big time actually). Thanks for the insight!
First of all I love the event structure and it totally changed the way I program labview. Together with the subpanel addition, it makes for very professional looking programs. Here's my version of the same problem:
I have an event structure on the main VI, and ~20 subpanels. I load various subvi's in the subpanel of the main VI as required. Each subvi has an event structure to handle GUI and incoming user events. I found the problem in the full blown operation, but the problem also appears when I only have one subpanel running, so only one event structure in a subpanel and one event structure in the main program.
I had the problem with a mouse down on a table, and with a doubleclick on a listbox. And indeed I had an attribute node (reference + property node in my case) to the listbox in the event case that handles the doubleclick. When removing the attribute node, no more buttons will stop to respond on the main panel. When you try to readout or access the listbox in any way in the event case that handles the double-click, it fails. It does not matter whether the "Lock front panel until the case for this event is completed" is true or false. After it fails, you have to unload all the code and reload before LV is able to see some of the buttons on the main panel again (LV7.1.1). You do not have to close LV just the VI's.
So my first work-around after reading your story was to drive a user event from the doubleclick event case. That user event case then does the stuff I want to do with the listbox. Did not work. I then added a delay of 1000 ms before accessing the attribute node in the other event case, that worked. I then moved all my stuff back into the original event case and added a delay there before accessing the listbox. 100 ms failed, 500 ms works. So at this point I would tend to unexpected behavior from LV which is timing dependent, not "Operator error".
There is never a problem in any of the ~200 events in the ~20 subpanels. It is always the main panel that is affected. The event handler simply does not "see" some buttons anymore (value change), for example the "mouse down" event would still work for a boolean buttton on the main panel whereas the "value change event" would consistently fail.

Can I get the event structure to NOT queue events?

I was wondering if it is possible to have the event structure not queue events that happen while the vi is executing code associated with another event. Basically, I have a toggle switch that, when "on", captures a live feed from a camera and displays it to the screen. This is done in a while loop that executes until the toggle switch is turned off. At this point, that event is done and the vi returns to the uppermost level of the event structure and resumes looking for events. The trouble is that the whole while the video capture was happening, the event structure was queueing events that were occuring during that time when the user was hitting other front panel buttons that had their own event associated with th
em and would not execute at that time. When the video capture toggle is turned off the event structure then executes any other events that were queued during that time and I don't want it to. I can't lock the front panel while the video capture is happening so the user can't push buttons because they have to be able to push the button to turn the video capture off. Any suggestions? Thanks in advance.

> I was wondering if it is possible to have the event structure not
> queue events that happen while the vi is executing code associated
> with another event. Basically, I have a toggle switch that, when
> "on", captures a live feed from a camera and displays it to the
> screen.
I think there are lots of other articles about this on devzone.
To summarize them, the key is that the event structure intentionally
synchronizes events with diagram execution. The typical way to do what
you want is to have the event start up another loop or subVI running
asynchronously.
Usually there ends up being one loop with an event structure in it.
Another loop that executes a statemachine, possibly as simple as just
two states of acquiring and not. Use the events to pr
od the other loop
between states via locals, globals, occurrences, etc.
Greg McKaskle

How does the event structure work & ...

How does the event structure work & and how to modify the case example if you want to change the name of the case? I haven't a look at the manual but nothing about event structure is mentioned.

I know how it works.. =P

How to control the event structure

What i am trying to do is when the condtion is true, i want the event structure to excute. But event structure wil not excute unless there the puch pattern changed, any idea how to do that ?
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Attachments:
Try.vi ‏95 KB

It's more likely he wants the sequence of events he has put together to run after the result changes once. If you change the logic to check the values after each change of numeric(2), he'll need to learn to check to ensure the last iteration wasn't already true. Otherwise, he's going to start the sequence over and over.
Really, you need to get away from the event structure entirely. It's not what you want. Your code lends itself to a state machine very well.
You'll want to ask yourself a few things:
1) Do I want my code to run continuously or do I just want to check the two numerics once? (your code currently does the second)
2) Do I want the user to be able to stop my code once the sequence starts? (this is generally a yes)
3) Do I want Path 6, Path 5, or the comparison to happen first? Do I want them all to run simultaneously? Do I need one before another? (currently you cannot predict which will happen first.)
Topics you'll need to understand are: state machines, data flow, case structures, timing, and race conditions. Right now, you're looking to get yourself into trouble.

Where is the event options in iPhoto with the new iOS 7 update on iPad?

Where is the event options in iPhoto with the new iOS 7 update on iPad?

You mean iPhoto the app or the native iOS Photos app?
I have both in my iPad running iOS7 and iPhoto has the Events as usual.

Does the Event Structure work with cRIO?

Basic question, I know, but I did search. Honest! LabVIEW lets me drop an Event Structure in code targeted for cRIO, but so far it's not working. Is there a secret? Or is it that event structures don't work with cRIO? TIA!
Jeff

Jeff,
According to these two NI documents, RT targets support the Event Structure only with dynamic events.
http://zone.ni.com/reference/en-XX/help/370622F-01/lvrtconcepts/rt_unsupportedets/
http://zone.ni.com/reference/en-XX/help/370622F-01/lvrtconcepts/rt_unsupportedvxworks/

Is there a way to add an event to the event queue handled by the event structure?

I am using an event structure to control the flow of a program. In one case I want to change the state of a switch and then have the event structure catch this exception and handle it. It works if the user toggles the switch, but doesn't seem to when it is done programmatically. Any suggestions.

Hello,
LabView User's manual says:
"Use Events for Direct User Interaction Only
Events wait only for direct user interaction on the front panel. Events do not work if you use VI Server, global variables, local variables, and so on to change VI or front panel objects programmatically."
However, you can have a look in Example Code, there's some applications generating events programmatically, maybe that helps you. (Search for event structure in support).
Hope that helps,
SBC

How to exit from the DO-while loop in the event structure

Hi all
I am just a beginner for Labview
I want to build a loop in the event structure, but when I enter in the loop, it seems the system is dead, and I can't exit the loop.
here I attached a simple sample.
In the sample. when I press the start_calculation button , the calculation start, but the system is dead, and I can't exit calculation loop.
actually, i just want switch the different operation by changing the event action.
anybody has a good idea about it??
thanks so lot
Attachments:
event_problem.vi ‏17 KB

Your problem is that you are trapped inside an event case. It is not a good idea to run extended code inside event cases, else the event structure cannot service other events.
Why don't you use the outer loop for everything? Now things don't step on each others toes. What good is an event structure if it cannot react at all times???
Message Edited by altenbach on 07-25-2008 12:26 AM
LabVIEW Champion . Do more with less code and in less time .
Attachments:
event_problemMOD.vi ‏17 KB

Calling Previous Event(s) in the Event Structure

I have a an event structure with 5 events doing different function. I want to create another event which would run 3 of the previous events with one click. Can anyone help me do that?

If you did go the route of a parallel State Machine to the Event Structure (loop), then you should consider using an Action Engine that keeps track of the current state and the past history. The Action Engine may have enough intelligence to determine if it is appropriate to roll back and how far..
As Andre mentionned, you do have to make sure the software is well designed in order to avoid any deadlock conditions.
RayR

IPS 5.0 installed where are the events?

Folks,
I just installed IPS 5.0 on a sensor 4210, i am reading the manual and i also got a trial license. But, i am still confussed, where do i see the events if some attacks my network, do i still use the event viewer? i know i should use VMS, but i want to find out if there was any other way to see the events?

he easiest way to see events is with IDM. Just https: to the management interface, the select monitor and events in IDM.

Are user events valid before the event structure executes?

If I create and register for a user event and immediately generate that event before my event structure has seen the registration refnum, is the event still guaranteed to be seen by the structure? That is, are events queued up? It works but I am wondering if I can rely on it. I am very sure that I can but I am creating some production code and want to be assured that I am not just taking advantage of a bug.
A picture is worth a thousand words.
=====================
LabVIEW 2012
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Generally, Felix's explanation is correct and the queue exists from the moment the register node executes, so the answer is that you can rely on this.
You should, however, be aware that when playing with dynamic registration you can experience some unexpected side effects, as you can see, for example, in this LAVA thread - http://lavag.org/topic/13607-dynamic-event-reregistration/
Another example would be this - http://lavag.org/topic/13970-unexpected-event-structure-non-timeout-behavior/page__view__findpost__p...
Or what happens if you split the registration refnum to more than one event structure (hint - NEVER do that).
Try to take over the world!

Where are the Events in the new Photo App in Yosemite?

I just updated from iPhoto to Photo and it seems like I lost the Events ("Ereignisse") of iPhoto and there is no option to show them. Can someone help?

I have the same question. Almost all of my smart albums were based on Events, and now all of these are broken.
Example, I had a smart album for best hikes of the year, and it compiled all 5 star photos from Events with "hike" in the name.

Event Structure Freezes Vi After Capturing The First Event

My Event structure catches the first instance of my button press but then it freezes my Vi. The reason is because of the while loop but I need the while loop to constantly read from a serial port and send data to a serial port. The vi included is stripped down to be just a while loop that does nothing. I have also tryed putting the event structure in the while loop, but the same thing is happening.
Any ideas?
Thanks,
Cason Clagg
SwRI
LabView 7.1, Windows XP

Also, put the button inside the event structure where it is acted upon, from LV help (suggest you read the entire events section of help):
When you trigger an event on a Boolean control configured with a latching mechanical action, the Boolean control does not reset to its default value until the block diagram reads the terminal on the Boolean control. You must read the terminal inside the event case for the mechanical action to work correctly. As a reminder, a note appears in the Edit Events dialog box when you configure a Value Change event on a latched Boolean control.
Refer to the Handling a Latched Stop Boolean Control in an Event Structure caveat for information about how to handle a latched Boolean control.
When you trigger an event on a Boolean control configured with a latching mechanical action, the Boolean control does not reset to its default value until the block diagram reads the terminal on the Boolean control. You must read the terminal inside the event case for the mechanical action to work correctly. As a reminder, a note appears in the Edit Events dialog box when you configure a Value Change event on a latched Boolean control.
Refer to the Handling a Latched Stop Boolean Control in an Event Structure caveat for information about how to handle a latched Boolean control.
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"It’s the questions that drive us.”
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How can i use the same front panel graph in more than one events in an event structure?

i want to display the signals from my sensorDAQ in a graph.but i have more than one event in the event structure to acquire the signal and display it in the graph.the first event is to acquire the threshold signals and its displayed in the graph as a feedback.after the first event is executed, i will call the second event,where the further signals are acuired and compared with the threshold signals from the event 1.my question is how can i use the same front panel control in more than two events in the event structure?please answer me i'm stuck.
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Hi,
I have attached here an example of doing the same using shift registers and local variables. Take a look. Shift register is always a better option than local variables.
Regards,
Nitzz
(Give kudos to good answers, Mark it as a solution if your problem is Solved)
Attachments:
Graph and shift registers.vi ‏12 KB
graph and local variables.vi ‏12 KB

Where is the Event Structure?

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