event structure cannot combine with other event and only run one time

[gary333]

Why It will always stuck when i Combine the "add new user" Event to the "Login" Event ??

It work for me when i separate two but "add new user"button can run but only one time for the above structure,program will stuck on the second time i press the "add new user"button

[gary333]

Anyone?

[Dennis_Knutson]

I don't see anything done correctly. You should have one event structure with multiple events. You're event structure needs to be inside a while loop. Don't use the run continuous nutrition. Don't use local variables. You have a classic race condition.

[gary333]

When i combine the "add new user"event to the "login"event ,the whole front panal stuck when i pressed "add new user"button

why would it happen?

[Dennis_Knutson]

Are you sure the login event has finished? Attach a VI with the correct design pattern.

[gary333]

can u please hint me how should i suppose to do it ? im not sure where is wrong

[Blokk · Accepted solution]

It was already told you, you should use only one Event structure and not 2. Also, avoid using local variables (better to store data in a shift register, and not in an indicator) how you do, it can cause nasty race conditions.

Actually here you just do not need other data storage since you have a file. Do not store data file in the root of the C drive, you may not have write permission. Use Default Data folder or the application folder.

I have attached a simple example. I guess this is a homework? Please make my help count: try to understand why your VI does not work, and try to find a solution by yourself. Modify my example, and play with it. This is how you can learn LabVIEW. If something is not clear, post here, and we can explain/help.

edit: at the "login" Event case, I do not check against whether the file exists or not. Fix this part, also gives some practice.

[gary333]

Thank you~

Im sorry bcos i dont understand just now...

Thanks for your sample

this is much appreciated.

[natasftw]

If you don't understand the answer that was given, you're in WAY over your head and the example won't really help you too much.  Instead of trying to push forward, take a few steps back.  Learn about LabVIEW.  Take free tutorials.  THEN, try to do what you'd like to program.