When i run a VI with the 'show front panel when loaded' and 'show front panel when called' options unchecked, the VI does not run.

[gsl]

I have an application in which many data aquisition processes have to run in the back ground. So, i use the runVI method to start all the data aquisition processes from a main Vi.

I observe that if the front panel is not opened, the data collection VIs dont run.If i check the either of the options 'show front panel when called' or 'show front panel when loaded' the VIs run. But the front panels are shown which i donot want. I tried making the main VI's front panel as front most but i dont hink it's a good solution. Why are the VIs not executed when when the front panel is not opened(the invoke node with runVI method is used)?

Thanks in
advance

[ian_fung]

Isn't it enough by setting your Window Appearance property as Default?

[waldemar.hersacher]

We have a lot of applications from LV 5.0 to LV 7.0 which load VIs through VI server and run VIs in the background. For all these VI the window apperance is set to default.

The starting VI will load the VI with Open VI Reference. Then you use Invoke Node>>RunVI with wait until finished set to FALSE. If you now close the reference the VI will be unloaded. Put a small wait between the Invoke Node and the Close reference.

The loaded VI must open a reference to itself and keep this reference open until it finishs.

If you build an application you have to add this VI as a dynamic VI to the build file. Be sure that in the VI Settings page for this VI "Remove Panel" is set to "No".

Your problem lies in the way LV loads and unloads VIs. A VI can be unloa
ded when no reference is open to the VI and the front panel is not open.

Waldemar