Question

I am having some trouble calling an objective-c class method from a C++ file. Example:

In my .h:

@interface MyClass : NSObject {
}
+ (void)myMethod:(NSString *)str;

In my .m:

+ (void) myMethod:(NSString *)str { ... }

In my .cpp:

??

How can you call myMethod since there is no class instance? Its essentially a static?

Thanks

Answer 1

Objects in C++ are incompatible with objects in Objective-C. You cannot simply call an Objective-C method from C++.

There are some solutions, however:

1. Use Objective-C++. Rename your .cpp to .mm, then you can use Objective-C syntax in your C++ code: [FlurryAnalytics myMethod: @"foo"];

2. Use direct calls to the Objective-C runtime system. I won’t tell you how to, because I really think you shouldn’t, and in fact that you don’t want to.

3. Write a plain-C interface. That is, in some .m file, define void myFunction(const char *str) { ... } and call that from C++. You can find an example of this here.