Hello World (new ARC enabled example)

Xcode, Interface Builder und Co. are very powerful tools, but sometimes they seem to make things a little bit more complicated than they really are. Here's a short program in Objective-C:

#import <Foundation/Foundation.h>
 
int main (int argc, const char * argv[]) {
    @autoreleasepool {
    
	// Hello World!
	printf("About to print the most important message...\n");
	NSLog(@"Hello World!\n");
	
    }
    return 0;
}

You can compile either with a simple Editor that supports this (e.g. CodeRunner or TextMate: Actions: Run) - or you use the clang (speak: C-Lang) compiler with Bash (Terminal.app):

cd ~/Path/to/HelloWorld.m
clang HelloWorld.m -o HelloWorld -framework Foundation
./HelloWorld

Hello World (old, non-ARC example)

Xcode, Interface Builder und Co. are very powerful tools, but sometimes they seem to make things a little bit more complicated than they really are. Here's a short program in Objective-C:

#import <Foundation/Foundation.h>
 
int main (int argc, const char * argv[]) {
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
    
	// Hello World!
	printf("About to print the most important message...\n");
	NSLog(@"Hello World!\n");
	
    [pool release];
    return 0;
}

You can compile either with a simple Editor that supports this (e.g. TextMate: Actions: Run) - or you use the gcc compiler with Bash (Terminal.app):

cd ~/Path/to/HelloWorld.m
gcc HelloWorld.m -o HelloWorld -framework Foundation
./HelloWorld

Objective-C Introduction

Objective-C versus ...

NeXTStep

Cocoa and Objective-C kind of belong to each other. Usually you'll hear that Objective-C is only useful on Mac OSOperating System – for instance Apple's OS X stands for the tenth version of the OS and bound to Apple Stuff only, but this is not true: While NeXTStep originated over 20 years ago, there's also GNUstep which aims to bring Cocoa to all major OSOperating System – for instance Apple's OS X stands for the tenth version of the OS (*nix & Windows):

Basically GNUstep's Project Center is like Xcode and Gorm is like Interface Builder.

...btw, that's where all the NS-Prefixes come from (NeXTStep), eg in NSObject, NSArray, ...



Diese Seite ist Teil des Werkmoduls iOS Development von Michael Markert für Interface Design / Fakultät Medien an der Bauhaus-Universität Weimar.