this is objective-c code:NSString *className = [GSGGUI_Shared getClassNameFromDescription:item]; Class cls = nil;
if(!(cls = NSClassFromString(className)))
C++ doesn't support reflection which mean you can't do something like convert a Class name to a real Class.
You could refer to ObjectFactory class in the editor/cocostudio module for more information about how to implement the reflection in c++.