Question

Do I have to DECLARE all private methods in .m class file inside

@interface ClassName()
  //Privare Methods
@end

before

@implementation ClassName
  // Implementation of Private & Instance methods
@end

for every method I am implementing & using OTHER THEN the instance methods (methods declared in .h file)?

X-Code 4 DOES NOT give me WARNING for ALL private methods but ONLY for few of them. For example, it warns me for methods I am calling inside gesture handler functions but not inside other routines/methods. I am confused as to declare all non-instance methods or just declare the ones I get warned for.

Answer 1

XCode won’t warn about methods that appear before the point of invocation:

@implementation 

- (void) foo:(float)x;
{
    NSLog(@"%f", x); // prints 15.000000
}

- (void) bar;
{
    [self foo:15.0]; // no warning
    [self baz:15.0]; // warning
}

- (void) baz:(float)x;
{
    NSLog(@"%f", x); // prints 0.000000 instead of 15.0
}

@end

It is strongly recommended to declare methods which you are warned about, the code above gives one example why.