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How to get Value change event from ActiveX component?

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Hi All,

 

LV 8.6.1

 

I try to get value change event from ActiveX component. I have browsed forum and examples through but I can't get an idea how to use "callback  vi". E.g. in example "ActiveX Event Callback for IE.vi" there is used "callback vi". I added an example where value change event and mouse down event are programmed to event structure. Mouse down event work okay but value change not. Can someone describe what I must add to my example vi that value change event works okay?

 

BR, Jim

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Here's the solution ! "Value change event" is not performed into event structure but into "Callback VI".
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Hi, Krsone

 

Thank you very much. Your example works perfect. I forget to mention that I need this event also to event structure. My code structure is producer-consumer and this value change event should be passed also to queue. Should I add variable to "callback vi" or is there any easier way ?

 

BR, Jim

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Jim,

 

in order to synchronize ActiveX callbacks with the producer/cosnumer, you have to either

- create an user event in the callback and capture this in you producer  or

- obtain the queue between producer and consumer in your callback and insert the appropriate element into the queue in the callback.

 

I think the second option is easier to implement but is more limited in its functionality.

 

hope this helps,

Norbert 

Norbert
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I modified the VIs for an upcoming User Group.  As Norbert B mentioned, I used user events to signal back to the main code that we got the DTPicker change event.

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Norbert-

 

14 posts to go... Congratulations in advanced (pre-enthusiast)!


Certified LabVIEW Architect
TestScript: Free Python/LabVIEW Connector

One global to rule them all,
One double-click to find them,
One interface to bring them all
and in the panel bind them.
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