Calling function in a different class file

[harrytheshark]

Basically I'm wondering how to call a function which is in another class file.
I've got

#import "myClassFile.h"

in the top of the class I'm calling from.

I'm calling it like this

[myClassFile myFunction];

Now in myClassFile.h I have

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>


@interface myClassFile : NSObject {

}

-(void)myFunction;
@end

Then in myClassFile.m I have this

#import "myClassFile.h"


@implementation myClassFile

-(void)myFunction
{
	NSLog(@"myFunction");
}
@end

When I come to running it I get

warning 'myClassFile' may not respond to '+myFunction'

Why can't a call my function from a different class file?
Thanks,
Tom

[nacht]

-(void)myFunction;

The "-" indicates an instance method. You need to create an instance ([[myClassFile alloc] init]) to call it.

You can also replace the "-" with a "+" to make it class-level, this is similar to declaring a function "static" in Java.

[harrytheshark]

Forget this post I just realised what you meant, I'm very tired lol.
Thanks again,
Tom

[nacht]

I would recommend starting by learning the basics of programming before messing with the intricacies of iPhone programming. While it is certainly possible to use Objective-C as a learning language, the resources out there for learning it mostly assume knowledge of another language, and iPhone development in particular has a variety of quirks inherent to a (relatively) new SDK and working on an external device or in a simulator.

How to think like a computer scientist: Learning With Python

The most relevant sections come later (e.g., Chapter 13), but it covers most of the basics. Python is a good language to start from for learning those basics.

If you prefer a C-derived language, there's always Java or C++, the last of which is closest to Objective-C.

If you really insist on getting started immediately with Objective-C:

[[myClassFile alloc] init] myFunction];

alloc allocates the memory.

init acts as a constructor.

myFunction is your function and can then be called after the object has been created.

[harrytheshark]

Thanks for the link.

Tom

[scleland]

Why dont we first discuss how Apple makes their money off of marketing before we get upset at the people trying to learn system programming?