Example Code

Windows Message Queue Library

Code and Documents


This collection of VIs allows VI code to receive and process windows messages. The examples can be used to intercept messages that normally go exclusively to the LabVIEW window (such as mouse messages). It can also intercept custom messages posted by other applications, much like our DAQ Events can post messages to applications.

If you are interested in the underlying DLL code, it is also provided. A firm grasp of C++ is necessary. The code also serves as an example of how to set an occurrence from a DLL.

Please read all documentation starting with the readme.txt file in the zip file.

See also the Example Program on 32-bit Windows Utilities (linked below).

Related Links:
Windows Utilities (32-bit)

Example code from the Example Code Exchange in the NI Community is licensed with the MIT license.


Great utility!.  I have a device that exists as an HID and I am trying to detect when one (upto 4 HID's) is inserted or removed.  I used this library to monitor for device change notifications for my device class.  The problem is that the code works in the DEV environment, LV 2014, but not in a built application. Reading the DLL source, it seems that calling from a LV built application was considered and noted as an issue?  Is that understanding correct.  


So the issues I want to resolve:

1. Where to put the DCE_EventEngine.vit   


Using a static VI in a sub-folder (DCE_Engine\...)

the Create Windows Message Queue.vi fails (inside Get Window Refnum.vi) with error 6002

VI, DCE_StartEventEngine works with the template in the DEV system.


What do I need to do to build an application with this code?

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Is this broken in LV64?