I just can't get SNew(SSpinBox).OnValueChanged() in my DetailsCustomization working

I really don’t get SNew(SSpinBox).OnValueChanged() working in my DetailsCustomization. I just want it to call a function from the same class.

SNew(SSpinBox).OnValueChanged (&MyClass::MyVoidFunction) - does not work
SNew(SSpinBox).OnValueChanged (this, &MyClass::MyVoidFunction) - does not work
SNew(SSpinBox).OnValueChanged (&MyClass::MyVoidFunctionWithFloatParameter) - does not work
SNew(SSpinBox).OnValueChanged (this, &MyClass::MyVoidFunctionWithFloatParameter) - does not work

I’m trying around for several days now but just can’t get it working.
What does it expect to call my function?
Please help me out here :slight_smile: