error handling with xcontrols

[Joel]

What is the best way to do error handling with xcontrols?  There is no obvious way to return an error cluster back.

 I've thought of four possible methods:

1) Incorporating the error cluster into the xcontrol's data cluster.  But then the error will only be handled if the xcontrol's data is explicitly read.  Since xcontrols have a lot of other functions, it might never be read.

2)Pop a dialog box with the error information.  This lead to repeated LabVIEW crashes  (100% CPU utilization, etc.)  (I'm using 8.2)

3) Write the error information to a global.  This seems to work, but it means that I have to poll the global.

4) Use a notifier.  I haven't tried this yet, so I don't know if it will work.

It doesn't help that xcontrols are hard to debug.

[TCPlomp]

Hi Joel,

what you could do is launch a VI in the init-state of the XControl via VI-server dynamically. And feed errors via a queue to this VI. If you kill the queue in the final state of the Xcontrol, the queue will generate an error and you can close the error-VI

Ton