topic Re: Disable event structure until in need in LabVIEW

Disable event structure until in need

Paradigm1999 — Fri, 11 May 2012 10:33:13 GMT

Dear All Expert,

Is there a way to disable or put the Event case structure to sleep until when we need its respond. The reason I am asking this is because when I am moving through a sequence of action and the event case of let say a mouse click occur, it will "memorise" that a button had been click.

When my sequence move to polling the event case for mouse click, without clicking the mouse button, this sequence is already completed as memorising the previous mouse click.

I wanted to ignored any event case happening during my sequencing until I poll it during one of the sequence and continue,

Is there a way to disable the event first? Pls help. Thanks a lot

Rif.: Disable event structure until in need

AndreaAngeloni — Fri, 11 May 2012 10:42:09 GMT

Ciao Paradigm,

I'm not an expert but I'd like to share my experience: I tried to do this but I've not been able to do it, and as far as I understood it is not possible. I got rid of it having care to disable all of the controls I didn't wanted to "buffer" actions.

Regards,

Andrea

Re: Disable event structure until in need

yenknip — Fri, 11 May 2012 11:07:30 GMT

Putting the event structure inside one of the cases of a state machine can be a perfectly valid application architecture. A quick fix would be to wire the timeout node.

However from your description, I would be more inclined to use a Queued state machine, with the event structure (producer) feeding extra states to the consumer. Thus the QSM can sit happily doing its thing and queuing the next state to itself and still allow quick responses to user events.

Re: Disable event structure until in need

Norbert_B — Fri, 11 May 2012 11:28:49 GMT

@yenknip wrote:

Putting the event structure inside one of the cases of a state machine can be a perfectly valid application architecture. [..]

This is indeed a valid application architecture, but the event structure is still "armed". So the event mechanism still enqueues, but they will not get worked on.

So i doubt that this helps the OP.

Norbert

Re: Disable event structure until in need

JonN — Fri, 11 May 2012 13:31:22 GMT

You could use the "Pane:Mouse Down?" event handler and set Discard? to prevent FP objects from triggering and then reset when needed.

Re: Disable event structure until in need

Yamaeda — Fri, 11 May 2012 13:35:26 GMT

2 solutions:

1. Use a case inside the event and do nothing.

2. Use dynamic event and register Void (look at mouse drag example)

Re: Disable event structure until in need

Ben — Fri, 11 May 2012 13:36:28 GMT

Sear4ch this site for

State Diagram

and

"Ton Nugget dynamic event"

The first search is to learn about state machines which should be used in place of sequence strcures even if the flow is straight line.

THe second will show a wonderful Nugget posted by Ton that taught me how to use Dynamic Event Registration which in layman's terms is a technique that lets you turn events on and off wheneve you need to do so.

Have fun!

Ben

Re: Disable event structure until in need

Mark_Yedinak — Fri, 11 May 2012 16:04:01 GMT

Check out our presentation from the last Chicago LabVIEW User's Group meeting. The entire meeting was covering events including the ability to arm/disarm events programmatically. I also posted something related in this thread.

Re: Disable event structure until in need

Paradigm1999 — Fri, 11 May 2012 16:16:36 GMT

Hi Mark,

I had read the Ton dynamic event and I am using a SM design although its not a QSM. My SM is non linear and had a page for Result waiting for user to click on the same 2D pictures and display the results.

I dont know how can the dynamic events helps in this case since all the event for all the 2D pictures is a mouse down event. When the mouse is click on any of the 2D pictures, it already register the event. When I come to the result state, it will straight away display the result without having the click on any mouse button again.

That is why I want the event to respone only when I am in the result state. Pls help. Thanks

Re: Disable event structure until in need

altenbach — Fri, 11 May 2012 16:24:35 GMT

Show us some code

Re: Disable event structure until in need

Paradigm1999 — Fri, 11 May 2012 23:33:55 GMT

Hi All,

Attached is the result page code. It suppose to act like a game where the picture appear at a random grid and show up. The user had to click on the correct 2D picture to level up after matching the same pattern

The problem I face now is that when the state machine is not in the Result page and the user had click on the 2D picture already, it will memorise the click and when it come to the Result state, the result will be generated and go to the next level if correct or stop at the start if wrong

Any solution for this?

Re: Disable event structure until in need

crossrulz — Sat, 12 May 2012 03:14:16 GMT

From what I was seeing, I'm thinking the state machine might not be the architecture you want. I'm thinking you could use a while loop with an event structure. The event structure would then take care of all of your logic. Keep some shift registeres to keep track of states. This way, you can use the "Lock front panel until this event case completes".

Re: Disable event structure until in need

Paradigm1999 — Sat, 12 May 2012 12:45:53 GMT

Hi Crossrulz,

I dont understand your point 🙂

Can you elaborate. My state machine is not the full code as I am still figuring out the event structure. At the game state, I will process a random code generation to sequence through the state diagram. Now my problem is when the state is finished, it will alway got to the result state for the appropriate click. However, before going to the result state, when the mouse button is click, it will register the click already. So I would like to disable the event until the result state is called.

Re: Disable event structure until in need

altenbach — Sat, 12 May 2012 17:29:02 GMT

@Paradigm1999 wrote:

The problem I face now is that when the state machine is not in the Result page and the user had click on the 2D picture already, it will memorise the click and when it come to the Result state, the result will be generated and go to the next level if correct or stop at the start if wrong

You would use one single event structure in the "Start" case, add "result" as a second condition to that same case. It will contain all possible events you need. (OK to start, mouse down, etc).

In the "mouse down" event cases use a case structure wired to the state that has an nearly empty default case, but does the appropriate state switching in the "result" case.

Re: Disable event structure until in need

altenbach — Sat, 12 May 2012 17:33:58 GMT

@altenbach wrote:
You would use one single event structure in the "Start" case, add "result" as a second condition to that same case. It will contain all possible events you need. (OK to start, mouse down, etc).
In the "mouse down" event cases use a case structure wired to the state that has an nearly empty default case, but does the appropriate state switching in the "result" case.

Here's a broken draft that shows some of these points. Most of the other code is missing, but it should give you some ideas.

Re: Disable event structure until in need

Paradigm1999 — Sun, 13 May 2012 15:39:21 GMT

Hi altenbach,

Can I ask a few question

1) How you create the VI Server Reference for individual Array A1 to A8

2) I need to identify which Array had been click. If you bundle all the Array mouse down event structure together, how can I check or know which array had been click?

Thanks a lot

Re: Disable event structure until in need

altenbach — Sun, 13 May 2012 16:21:08 GMT

Paradigm1999 wrote:
1) How you create the VI Server Reference for individual Array A1 to A8

2) I need to identify which Array had been click. If you bundle all the Array mouse down event structure together, how can I check or know which array had been click?

Right-click the terminal...create reference.
Simply look at my code. I create an array of references. The event terminal outputs the reference of the control that has been clicked. If you search the array of references for it, the resulting index will give you the control that fired the event. That's all you need. (make sure you arrange the array in the correct order to simplify the assignments).

Re: Disable event structure until in need

mahu — Sun, 13 May 2012 17:13:27 GMT

You did already tried with cursor vi, with get busy.vi can disable click while completing the process.

Re: Disable event structure until in need

Paradigm1999 — Mon, 14 May 2012 05:19:08 GMT

Hi Mahu,

what you mean by cursor.vi and busy.vi? Where can I get these VI?

Re: Disable event structure until in need

Paradigm1999 — Mon, 14 May 2012 05:55:45 GMT

Hi Mahu,

I saw the set busy.vi but it cause the cursor to be in busy icon. Ppl may misunderstood it as the VI is not ready and is still loading. Is there a way to disable the cursor without marking it looks busy?