SetScalarParameterValue inaccessible

In vs2017, UMaterialInstanceDynamic could not use SetScalarParameterValue which is inaccessible, any help?
It seems that all Set*Parameter function is inaccessible…

It seems 4.20 many public turn into private, C++ Transition Guide for 4.20 - C++ - Epic Developer Community Forums

If you are using UE 4.20, then it is still accessible.

Everything after GENERATED_UCLASS_BODY is public by default. If it were GENERATED_BODY, then it would be private. I tested it and it compiles successfully

260032-example-2.png

vs2017 compiled no error ,i think the intellisense was in bad work…it notified function is inaccessible