Although there’s already a “hello world’ floating out there for the iPhone, it involves a number of complicated classes. I decided to simplify and create a new “Hello World” from scratch based only on UIWindow, UIView and UITextView. The code follows after the jump. Makefile CC=arm-apple-darwin-cc LD=$(CC) LDFLAGS=-lobjc -framework CoreFoundation -framework Foundation -framework UIKit -framework LayerKit -framework CoreGraphics all: SampleApp SampleApp: mainapp.o SampleApp.o $(LD) $(LDFLAGS) -v -o $@ $^ %.o: %.m $(CC) -c $(CFLAGS) $(CPPFLAGS) $< -o $@ clean: rm -f *.o SampleApp mainapp.m #import <UIKit/UIKit.h> #import "SampleApp.h" int main(int argc, char **argv) { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; return UIApplicationMain(argc, argv, [SampleApp class]); } SampleApp.h #import <CoreFoundation/CoreFoundation.h> #import <Foundation/Foundation.h> #import <UIKit/CDStructures.h> #import <UIKit/UIWindow.h> #import <UIKit/UIView-Hierarchy.h> #import <UIKit/UIHardware.h> #import <UIKit/UIKit.h> #import <UIKit/UIApplication.h> #import <UIKit/UITextView.h> #import <UIKit/UIView.h> @interface SampleApp : UIApplication { UIView *mainView; UITextView *textView; } @end SampleApp.m #import "SampleApp.h" @implementation SampleApp - (void) applicationDidFinishLaunching: (id) unused { UIWindow *window; struct CGRect rect = [UIHardware fullScreenApplicationContentRect]; rect.origin.x = rect.origin.y = 0.0f; window = [[UIWindow alloc] initWithContentRect: rect]; mainView = [[UIView alloc] initWithFrame: rect]; textView = [[UITextView alloc] initWithFrame: CGRectMake(0.0f, 0.0f, 320.0f, 480.0f)]; [textView setEditable:YES]; [textView setTextSize:14]; [window orderFront: self]; [window makeKey: self]; [window _setHidden: NO]; [window setContentView: mainView]; [mainView addSubview:textView]; [textView setText:@"Hello World"]; } @end

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