How to use a event structure with a state machine

First, I would like to inform you that I only work on LabView part time, and have much to learn.  Anything I do learn, I usually forget until I need it again, because I only work on it part time.
Using your StopWhileLoopMOD[1].vi, I am trying to put a state machine inside the event structure.  
Related link:
Here is my application:  on the front panel, the user can select any combination of 7 different tests.  I have created cases to perform each step of each test in the correct order, but if the user presses stop, the tests won't stop because some of the cases have a while loop inside the event structure (like you mentioned is a bad idea).  The user should be able to stop the test, reselect tests to perform, and re-start the tests. 
When the start button is pressed for the event structure, I need all the cases to run in the proper order, unless stop is pressed.
In the past I have indexed an array and used that to run the state machine, but it won't stop immediately.  
I have sub VIs that are built in while loops because the outputs of the product needs time to stabilize.  The state machine stops and waits up to a certain number of iterations.  If it passes the test, the while loop stops and the next state starts.  If it takes too long, it exits and reports an error.  Maybe I need to just use the state machine and not an event structure?
Is there a good example of an event structure?
metzler CLAD
Go to Solution.

I'm not sure exactly what you are asking, but it sounds like you want to script a bunch of tests and if the user says stop, to immediately stop the current test and abandon the others?  I'm going to assume that you know how to clear the array so that it will abandon the others, so I'm guessing that you are having trouble abandoning the current test?  If this is indeed the case, then the problem is that you are not able to propagate the message from the main VI FP which is the GUI to the sub vi which is the test, where the test may or may not have a GUI (FP visible) of it's own.  Threading was the first thing to come to mind, but this may not be necessary using events.
You can do this by passing a refnum of the stop button to the subVI, where you can then add that wait to the event case structure.
I've attached 2 VIs, which is just a loop displays the count*2 (number of seconds passed since running) that will call and then check to see if the stop button is pressed. is by no means a state engine, it is just a simple loop for demonstration purposes. just waits 2 seconds and leaves, it is a better structured state engine with an init state to start a poll case to wait for events and an exit state to clean up.  You can modify this any way you wish to get it to do what you want.  You will note that even if is being executed, it will terminate immediately when the stop button is pressed.
Hope this helps.
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