stop a while loop in subvi

Hi,

I have a subvi which has a while loop, and It is located in my main vi in a sequence structure, I want to stop the loop inside of the subvi using a boolean in main vi.

I tried global variable but It didn't work since the stop botton in my main vi doesn't get updated when the program is running...

could you please help me?

I appreciate any ideas

thanks

Darya