How to use global variable in MATLAB discrete-event system block (not MATLAB Function Blocks)?

I want to use global variable in a way like Resource Scheduling Using MATLAB Discrete-Event System and Data Store Memory Blocks. Like the following: After defining the parameter in a Data Store Memory block and declare the corresponding parameter in a MATLAB Discrete-Event System block, that block can access the value. But I can't implement this feature in my project. I have looked up a lot of information, but none of it has helped. Please help me solve this problem. Thanks!

The information from the diagnostic viewer is:

Warning:System object ignores the global variable 'BoardDataCollectionProcessBoxDatum1' added during 'DatumEntry' execution. The global variable is either not declared in 'DatumEntry' or is declared while using the MATLAB debugger.

[YOUNG]

'DatumEntry' is the function in the upper class of the class that I want to use the global variable.

Answer 1

[Fangjun Jiang]

Use Global Variables in System Objects

https://www.mathworks.com/help/simulink/ug/use-global-variables-in-system-objects.html#bvf2uux

[YOUNG]

It can not work. Can you explain the warning information I provided?

[YOUNG]

It seems that I have to declare the global variable in some specific simevents function.