Event Structure Using Old Values After Value Change of an Indicator

Updated May 24, 2023

Reported In

Software

  • LabVIEW

Issue Details

I have configured an event structure that triggers when I change the value of a numeric control as follows:



The event is triggered when I change values. However, the indicators in the event structure are reading the older values. Can I change some setting in the event structure to use the new value?
 

Solution

This behaviour is intended, as LabVIEW follows the Data Flow logic.

When the control is outside of the event structures, the value from the tunnel used inside the structure. Looking at the data flow logic of LabVIEW, you will understand, that the event structure can only be executed, when all inputs of the event structure are available. Therefore, it looks like you use the old value.

You can move the controls inside the event structure in the following manner to ensure that new values are used:



Alternatively, you can also configure the Event Data Node to output the New Value:
image.png

Additional Information

Another reason, why you get the old value instead of the new value is, if you don't use the "Value Change" Event, but the "Mouse Down" Event.

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