topic Re: Updating Labview.exe front panel from python in LabVIEW

Updating Labview.exe front panel from python

iveco — Tue, 08 Aug 2006 06:13:39 GMT

Hi

Is it possible to update a labview.exe front panel from python?

I tried this:
import win32com.client
labview = win32com.client.Dispatch("Labview.Application")
VI = labview.getvireference(r'python.vi')
VI.setcontrolvalue('Numerisch','5')

and it works fine. But when i replaced the python.vi trough a compiled python.exe i get this errormessage:

I tried this:
import win32com.client
labview = win32com.client.Dispatch("Labview.Application")
VI = labview.getvireference(r'python.exe')
VI.setcontrolvalue('Numerisch','5')

Traceback (most recent call last):
File "<interactive input>", line 1, in ?
File "<COMObject Labview.Application>", line 2, in getvireference
com_error: (-2147352567, 'Ausnahmefehler aufgetreten.', (5507, 'LabVIEW', 'LabVIEW :LabVIEW: Datei nicht gefunden. Die Datei wurde eventuell verschoben oder gel\xf6scht, oder der Dateipfad wurde bez\xfcglich Ihrer Plattform nicht korrekt formatiert. Beispiel: verwenden Sie \\ als Pfadseparator auf Windowsplattformen, : auf Macintosh u', None, 0, 0), None)

Is it possible to updating a labview exe front panal from python?

regards

Re: Updating Labview.exe front panel from python

TCPlomp — Tue, 08 Aug 2006 07:09:55 GMT

Hi Iveco,

have you tried updating the value from another VI (not in the executable!)? I think you are calling the wrong application, i'm not fully positive about this but that might be a problem.
First make sure the VI-server is enabled, and the python.vi is exported.

Ton

Re: Updating Labview.exe front panel from python

iveco — Tue, 08 Aug 2006 07:41:16 GMT

Hi Ton

import win32com.client
labview = win32com.client.Dispatch("Labview.Application")
VI = labview.getvireference(r'C:\TEMP\python.vi')
VI.setcontrolvalue('Numerisch','5')

this works fine. that means i can change the value in the python.vi. But when I compile the vi to python.exe it doesnt work.

How can I enable the vi server?

regards

Marcel

Re: Updating Labview.exe front panel from python

TCPlomp — Tue, 08 Aug 2006 10:36:57 GMT

That should be done in the build settings, AND you should refer to the VI as c:\temp\executable.exe\python.vi

Ton

Re: Updating Labview.exe front panel from python

iveco — Wed, 09 Aug 2006 11:57:03 GMT

Hi all

It still doesnt work. I dont know why.

The current python code:

import win32com.client
labview = win32com.client.Dispatch("Labview.Application")
VI = labview.getvireference(r'C:\TEMP\python.exe\python.vi')
VI.setcontrolvalue('Numerisch','5')

I registered with ccrpRegUtil.exe the builded tlb file.(Not sure its necessary)
Activex Server is active at the builder config.

when I change VI = labview.getvireference(r'C:\TEMP\python.exe\python.vi') to VI = labview.getvireference(r'C:\TEMP\python.vi')
and then I use the vi it works. with the compiled python.exe(with activex server)not.

I dont know maybe Im to stupid.

regards

Marcel

Re: Updating Labview.exe front panel from python

iveco — Fri, 18 Aug 2006 13:45:00 GMT

Thank you all for your help.

The Solution:

import win32com.client
labview = win32com.client.Dispatch("Python.Application")
VI = labview.getvireference(r'c:\temp\python.exe\python.vi')
VI.setcontrolvalue('Numerisch','5')

regards

Marcel

Re: Updating Labview.exe front panel from python

Jarrod_S. — Fri, 18 Aug 2006 13:53:18 GMT

Excellent! I'm glad you got it working...

Since you are interested in this area, you might check out this example program. I know it is a side-step from what you are working on, but it's very interesting. The idea is to wrap the LabVIEW ActiveX Server into a .NET object and then use IronPython code to manipulate LabVIEW objects from within a LabVIEW VI! It's a neat way to blend textual and G code into one.

http://community.ni.com/examples/using-ironpython-from-labview/

P.S. This is from our new community sight. Feel free to look around or post any code that you created. Happy coding 🙂

Re: Updating Labview.exe front panel from python

mar_eng — Tue, 04 Dec 2007 21:41:26 GMT

Hi,

accessing a control with python works fine, but how can I read/write a control wich is part of a "Tab"?

Thanks,

Marcus

Re: Updating Labview.exe front panel from python

YogeshaYS — Thu, 22 May 2008 05:16:43 GMT

Hi all,

I am new to this.
I want exchenge the data from pyton to labview and vice versa.
can u give the steps to do the above.
Please give with an example.
I amtrying really hard and i dint get the same.

Thanks in advance,
Yogesh

Re: Updating Labview.exe front panel from python

baesi — Thu, 22 May 2008 06:54:35 GMT

1. Unzip python.zip
2. Copy all files into c:\temp
    --> c:\temp\labview.py
    --> c:\temp\python.exe
    --> c:\temp\python.vi ......and so on

3. Open dos shell
4. change dir to c:\temp
5. Open Pythonwin
6. PythonWin: File Open c:\temp\labview.py
7. Run --> Ok

Now it should work

Re: Updating Labview.exe front panel from python

baesi — Thu, 22 May 2008 06:57:05 GMT

With dos shell it doesn't work. I dont know why, but I dont have the time to check it.
But this has worked.

1. Unzip python.zip
2. Copy all files into c:\temp
    --> c:\temp\labview.py
    --> c:\temp\python.exe
    --> c:\temp\python.vi ......and so on

3. Open Pythonwin
4. PythonWin: File Open c:\temp\labview.py
5. Run --> Ok

Now it should work

Re: Updating Labview.exe front panel from python

baesi — Thu, 22 May 2008 06:59:25 GMT

sorry with dosshell it doesnt work.

1. Unzip python.zip
2. Copy all files into c:\temp
    --> c:\temp\labview.py
    --> c:\temp\python.exe
    --> c:\temp\python.vi ......and so on

3. Open Pythonwin
4. PythonWin: File Open c:\temp\labview.py
5. Run --> Ok

Re: Updating Labview.exe front panel from python

Mathan — Thu, 22 May 2008 08:36:17 GMT

Dear baesi,

Could you please attach that pythonwin also please....

Thanks,

Mathan

Re: Updating Labview.exe front panel from python

baesi — Thu, 22 May 2008 08:43:51 GMT

I' affraid not, but you can download it here:
Python:
http://www.python.org/download/releases/2.3.5/

Pywin:
http://starship.python.net/crew/mhammond/win32/Downloads.htmlbaesi

regards

baesi

Re: Updating Labview.exe front panel from python

YogeshaYS — Thu, 22 May 2008 10:12:20 GMT

Hi Baesi,

Thanks for the reply.
I hav follwed, what u said.
I want to giv some data from lLV to Python.
Say some x is a variable in python script. I want giv the value to x from LV.
Then the result i have to monitor in LV.
Please guid me with this.

Thanks in advance,
Yogesh

Re: Updating Labview.exe front panel from python

macenc87@yahoo.co.in — Thu, 18 Apr 2013 03:28:23 GMT

Hello,

Thanks for the post. But I have noticed one problem.

The examples posted by you works fine.

But, when you add the Labview file under a project then it doesn't.

I mean, add your Python.vi under one project and then try to run it, it doesn't work. It is not showing any update from python script.

What I think is - we need different dispatch method for calling a VI under a project.

(Dispatch(LabVIEW.Application) will create a reference for an application. If you want to refer to a VI which is under one project then it might need different referencing method)

If you know the solution please post the answer and if you are not clear about the question then I will be happy to post elaborated question.

Re: Updating Labview.exe front panel from python

Avanness — Mon, 09 Nov 2015 21:02:10 GMT

Does anyone know what this error mean when I run:

Code:

import win32com.client
labview = win32com.client.Dispatch("Labview.Application")
VI = labview.getvireference(r'C:\Test.vi')
VI.OpenFrontPanel()

Error:

Traceback (most recent call last):
File "C:\Test.py", line 4, in <module>
VI.OpenFrontPanel()
TypeError: 'NoneType' object is not callable

Re: Updating Labview.exe front panel from python

macenc87@yahoo.co.in — Tue, 10 Nov 2015 01:17:09 GMT

Hello Avannes, Currently I am not using LabVIEW a lot but this was one of the problem I faced.
I think you have created a new project under which you have created a new vi. And I guess you are trying to control the front panel elements in that VI.

if yes, that means while calling any VI in any project it is not being called as an object. This can be solved as below.

Open the project window (not the vi). In the project window, observe the bottom line ( not the project contents, project window bottom line). Right click on that and choose the option which says ' application as object'.

Let me know if you can find it. If not then I will post with screen shots next week as diwali holidays are on in India!!

Re: Updating Labview.exe front panel from python

THunter — Thu, 10 May 2018 13:44:54 GMT

One thing I don't understand:

    --> c:\temp\labview.py
    --> c:\temp\python.exe
    --> c:\temp\python.vi

Where are these files coming from? Ok I have my python file and my .vi file, I understand that. But where are python.exe, python.bld and python.tlb files coming from? I probably need them, because I cannot compile my own .py file. I can compile your example though.. So something is missing.

Re: Updating Labview.exe front panel from python

THunter — Fri, 11 May 2018 09:14:12 GMT

I managed to compile my .py file. I don't need any of these .exe and other files, only the .vi and the .py. Adjusted the path according to that, and it worked just fine!