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LabVIEW Idea Exchange

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RyanWright

Modify behavior of value change event for LabVIEW controls

Status: Declined

Any idea that has received less than 3 kudos within 3 years after posting will be automatically declined.

Currently, the behavior of LabVIEW controls is to generate a value change event even when the user enters the same value as the current control value.  This means that for situations where you are trying to respond to a control change (e.g. combo box), such as performing switching operations,  redundant operations get performed by default if the user changes his mind and doesn't actually change the value of the front panel control.  In the case of switching, for example, that causes relays on the switch modules to be open and closed unnecessarily, resulting in unnecessary aging of the switch relays which have a finite lifetime.  Obviously, this could be handled with some code in the event handler for such an event, but it seems strange for a value change event to get generated when the value of the control didn't actually change.  At a minimum, it would be nice if there were an option somewhere, such as in the LabVIEW options dialog, where the user could specify whether selecting the same value in a front panel control generated a Value Change event or not.

1 Comment
Darren
Proven Zealot
Status changed to: Declined

Any idea that has received less than 3 kudos within 3 years after posting will be automatically declined.