How to create global functions in Objective-C

Question

I\'m developing an iphone app and I need to have some functions to use globally in my classes.

But how can I do this?

I just tried to create functions.

Answer 1

Two options here. First is create a class method in a static class:

Header:

#import 

@interface GlobalStuff : NSObject {}

+ (void)printTest;

@end

Implementation:

#import "functions.h"

@implementation GlobalStuff

+ (void) printTest {
  NSLog(@"test");
}

Call using:

#import "functions.h"

...
[GlobalStuff printTest];

The other option is to declare a global function instead of class:

Header:

void GSPrintTest();

Implementation:

#import 
#import "functions.h"
void GSPrintTest() {
  NSLog(@"test");
}

Call using:

#import "functions.h"
...
GSPrintTest();

A third (bad, but possible) option would be adding a category to NSObject for your methods:

Header:

#import 

@interface NSObject(GlobalStuff)
- (void) printTest;
@end

Implementation:

#import "functions.h"

@implementation NSObject(GlobalStuff)
- (void) printTest {
  NSLog(@"test");
}
@end

Call using:

#import "functions.h"
...
[self printTest];