front panel iced when i combine event loop and while loop

[CyGa]

Why my front panel is completely iced when i use this code??

[becktho]

Actually this is not a bug. This is behaviour of your code. Unless the inner while loop is not stopped, the vi won't react although the events of the buttons are generated an catched by the event structure.

[Norbert_B]

zyl7,

becktho is completly rigth, this is expected behaviour. You are running into one caveat with event-structures: Don't stack UI-controlled loops (stop button!) within event-structures!
You can find a small list of "Not to Do's with event structures" here.

Norbert B.
NI Germany

[CyGa]

Does that mean i cannot use a while loop inside an event structure?

[becktho]

Basically you can do whatever you want.

But it is not intended to use this way. Loops or other blocking calls (like dialogs or message boxes) in an event structure, are absolute "don't"s.

I suggest you to have a look at the producer/consumer pattern, which is very useful in combination with an event structure.

[Norbert_B]

zyl7,

well, you can, but it should not be terminated by the UI. If the loop terminates on its own, thats quite ok. But you should keep in mind that the eventstructure itself will keep on queueing events for UI-interaction from the customer, so if the loop itself runs a long time, the behaviour would NOT be very nice.
If you need an architecture which can handle such cases, you should take a look into the frameworks in the VI templatebrowser (select File->New)

Norbert B.

[CyGa]

Ok!!! thank you very much!!