Method hook

typedef IMP *IMPPointer;

BOOL class_swizzleMethodAndStore(Class class, SEL original, IMP     replacement, IMPPointer store) {  
    IMP imp = NULL;  
    Method method = class_getInstanceMethod(class, original);  
    if (method) {  
        const char *type = method_getTypeEncoding(method);  
        imp = class_replaceMethod(class, original, replacement, type);  
        if (!imp) {  
            imp = method_getImplementation(method);  
        }  
    }  
    if (imp && store) { *store = imp; }  
    return (imp != NULL);  
}

@implementation NSObject (FRRuntimeAdditions)  
+ (BOOL)swizzle:(SEL)original with:(IMP)replacement store:  (IMPPointer)store {  
    return class_swizzleMethodAndStore(self, original, replacement,     store);  
}  
@end


@implementation NSView (MyViewAdditions)


static void MySetFrame(id self, SEL _cmd, NSRect frame);  
static void (*SetFrameIMP)(id self, SEL _cmd, NSRect frame);


static void MySetFrame(id self, SEL _cmd, NSRect frame) {  
    // do custom work  
    SetFrameIMP(self, _cmd, frame);  
}


+ (void)load {  
    [self swizzle:@selector(setFrame:) with:(IMP)MySetFrame store:(IMP  *)&SetFrameIMP];  
}

@end