Question

I am trying to store callbacks in a dictionary.

• I can’t use blocks as the iPhone doesn’t support this (unless you use plblocks).
• I tried using functions, but apparently NSMutableDictionary doesn’t allow these pointers (wants an id)
• I tried using class methods, but I couldn’t find a way to obtain a pointer to these
• I could try using functions with the c++ stl hashmap (if it is supported in Objective C++), but apparently this can slow compilation times.
• I could try storing both a class and a selector, but that seems rather messy.

What would be the best way to do this?

Answer 1

If you know what you are doing with pointers, you can wrap them up with NSValue. You can then put NSValue in a dictionary.

To insert:

[myDict setObject:[NSValue valueWithPointer:functionName] forKey:myKey];

For retrieval:

NSValue* funcVal=(NSValue*) [myDict objectForKey:myKey];
returnType* (*func)()=[funcVal pointerValue];