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Bug in LV 7.1's handling of double-click events.

NI Support,
 
In my application, user selects item from a listbox with a button or a double-click. Desired behavior is for the listbox to advance to the next item (mod array length) after button press or double-click. Labview processes the button press correctly, but the double-click is handled incorrectly, as follows:
 
Labview catches the double-click event and passes to my application for processing. I process the event and advance the list. Labview then throws a second untrappable event that "selects" an item in the listbox based on the original double-click location. Since this processed after I have already completely my response to the double click, it has the effect of undoing my advance. Workaround is to add a few hundred ms of delay before acting on the double-click event.
 
The attached VI illustrates the problem.
 
By the way, it frosts me that I cannot mail applications engineering directly without an active support contract when filing bug reports. Filing bugs is not requesting support; it is helping NI make LabView better. It takes time to rewrite a malfunctioning VI in a way suitable for submission to NI as a bug report.
 
Sincerely yours,
 
Rob Calhoun
 
Message 1 of 4
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Working with events can sometimes be interesting.  I concentrated my efforts more on fixing the issue than trying to determine if this is a bug or not.  I modified your code slightly to filter events based on click type and I think it is working the way you intended.  Let me know it is not quite right.
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Message 2 of 4
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Chaos,

I still think this is a bug, but your workaround is much nicer than mine! I had to add a substantial delay to the event processing to reproducibly obtain the result desired, and there's no guarantee that would work right on another machine. Yours works without adding any delays.
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Message 3 of 4
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Hi Rob,

Thank you for your feedback. R&D is aware of that issue and is working to improve it in future versions of LabVIEW. We are also working to improve the bug report process from our website. I apologize for the inconvenience.

Regards,
Chris J
National Instruments

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Message 4 of 4
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