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string control value change event not triggering

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thanks for all the posts.......

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Message 11 of 15
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Well, I don't understand why you need an event for each digit, even if it's scanned, but that's your call.

 

You can consider a couple of options:

1... Have a SCAN / MANUAL switch, which changes the property of the control that accepts the code from the scanner. (UPDATE VALUE WHILE TYPING is a programmable property).

Kind of ugly, but do-able.

 

2... Have TWO controls.  One the user sees and can type into, another one that's hidden and the scanner types into. (Hiiden controls can still generate events).

 

Looking at this part:

if the user needs to press the enter key or click on the front panel after ever scan of a barcode scanner that would be annoying.

 

You want the scan to be a complete operation - scan --> event... scan---> event.

 

Not scan <enter> - event... scan <enter> event.

 

I can see that.

 

But I don't see how to get there unless you can guarantee that all scans are 10 digits or end with a ? or something easily detectable.

Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com


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Blog for (mostly LabVIEW) programmers: Tips And Tricks

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Message 12 of 15
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You want the scan to be a complete operation - scan --> event... scan---> event.

 

this is exactly what i want, but the event is only triggered when i click on the front panel if i use the barcode scanner.

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Message 13 of 15
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Then your only choice is to detect the VALUE CHANGED yourself.

 

three options:

 

1... Count N digits assuming a fixed length code.

2... Detect each digit via the existing VALUE CHANGED event, and set a timer for now + 50 mSec (or something).  When the timer expires, declare it to be done and use the value. (each digit received extends the deadline).

3... if the code has a terminating character from the scanner, use that.

Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com


LinkedIn

Blog for (mostly LabVIEW) programmers: Tips And Tricks

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Message 14 of 15
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yeah i think option 1 as johnsold previously posted......

thanks all...........

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Message 15 of 15
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