iPhone - How to modify a static library (.a file)

Question

I was given an static library (.a extension file) that I have to use in a project, however I need to modify some of the source code before it is useful to me. What is the best way to accomplish this?

Answer 1

The easy-but-most-of-the-time-not-applicable solutions are subclassing or extending.

You can also try to decompile the .a file if its licence authorizes it: cf. Decompiling Objective-C libraries, but it can be tricky and/or illegal.

Answer 2

You cannot modify a static library, your best bet is to try to get access to the sources or ask the author to modify it for you.

Answer 3

You may use a Objective C extension.

For example, there's a [MyClass myMethod] in the .a lib, and you want to change this one, the following code might be used:

#import "MyClass.h"
@interface MyClass( CategoryName )
-(void)myMethod;
@end

@implementation MyClass( CategoryName )
-(void)myMethod
{
    //new implementation goes here
}
@end

Answer 4

You cannot modify a library, only extend. That's kind of the point - to distribute the functionality behind your code without people being able to read it.