MainViewController.m

//
//  MainViewController.m
//  firstapp
//
//  Created by Scott on 4/17/13.
//  Copyright (c) 2013 swclark. All rights reserved.
//

#import "MainViewController.h"

@interface MainViewController ()

@property (nonatomic, strong) UITextField *textField;
@property (nonatomic, strong) UILabel *label;

@end

@implementation MainViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
	// Do any additional setup after loading the view.
    self.textField = [[UITextField alloc] initWithFrame: CGRectMake(10.0f, 30.0f, 300.0f, 30.0f)];
    self.textField.delegate = self;
    
    // changes the border style so the text field appears onscreen
    self.textField.borderStyle = UITextBorderStyleRoundedRect;
    
    /*
     add the text field to the main view 
     UITextField and other UI classes are subclasses of UIView and thus,
     can be added into the View heirarchy
    */
    [self.view addSubview:self.textField];
    
    // create the button
    UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    
    // set the button's frame
    button.frame = CGRectMake(110.0f, 200.0f, 100.0f, 30.0f);
    
    // set the target, action, and control event
    [button addTarget:self action:@selector(buttonPressed) forControlEvents:UIControlEventTouchUpInside];
    
    // add the button to the main view
    [self.view addSubview:button];
    
    // create the label
    self.label = [[UILabel alloc] initWithFrame:(CGRectMake(115.0f, 150.0f, 200.0f, 30.0f))];
    self.label.text = @"Hello World!";
    [self.view addSubview:self.label];
}

- (void)buttonPressed
{
    self.label.text = self.textField.text;
}

- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
    // this tells the OS to remove the keyboard from the forefront
    [textField resignFirstResponder];
    
    // instead of adding a line break the text field resigns;
    return NO;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end