Simple Hello world Program

Make sure you HelloWorldViewController.h file looks like:

and IBOutlet and IBAction Should be connected to view.

//

//  HelloWorldViewController.h

//  HelloWorld

//

//  Created by Paul Peelen on 2011-03-14.

//  Copyright 2011 9697271014. All rights reserved.

//

 

#import <UIKit/UIKit.h>

 

@interface HelloWorldViewController : UIViewController {

    UILabel *textLabel;

}

 

@property (nonatomic, retain) IBOutlet UILabel *textLabel;

 

- (IBAction)changeTheTextOfTheLabel;

 

@end

Now, we need to add our new function. Add the following just below the } of the dealloc function.

- (IBAction)changeTheTextOfTheLabel

{

[textLabel setText:@"Hello, World!"];

}

Your HelloWorldViewController.m should now look like:Now what did we do? Well, we added the functionality of our “changeTheTextOfTheLabel” function. Whenever this function is called, the text of the label will be set to “Hello, World!”.

//

//  HelloWorldViewController.m

//  HelloWorld

//

//  Created by Paul Peelen on 2011-03-14.

//  Copyright 2011 9697271014. All rights reserved.

//

 

#import "HelloWorldViewController.h"

 

@implementation HelloWorldViewController

 

@synthesize textLabel;

 

- (void)dealloc

{

[textLabel release];

[super dealloc];

}

 

- (IBAction)changeTheTextOfTheLabel

{

[textLabel setText:@"Hello, World!"];

}

 

- (void)didReceiveMemoryWarning

{

// Releases the view if it doesn't have a superview.

[super didReceiveMemoryWarning];

 

// Release any cached data, images, etc that aren't in use.

}

 

#pragma mark - View lifecycle

 

/*

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.

- (void)viewDidLoad

{

[super viewDidLoad];

}

*/

 

- (void)viewDidUnload

{

[super viewDidUnload];

// Release any retained subviews of the main view.

// e.g. self.myOutlet = nil;

}

 

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation

{

// Return YES for supported orientations

return (interfaceOrientation == UIInterfaceOrientationPortrait);

}

 

@end