- (void)viewDidLoad {

    [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

    UIView *redView = [[UIView alloc] init];

    redView.frame=CGRectMake(0, 100, 100, 200);

    redView.backgroundColor=[UIColor greenColor];

    [self.view addSubview:redView];

    UIView *greenView =[[UIView alloc]init];

    greenView.frame=CGRectMake(100, 100, 100, 200);

    greenView.backgroundColor=[UIColor redColor];

    [self.view addSubview:greenView];

    UIView *blackView =[[UIView alloc]init];

    blackView.frame=CGRectMake(200, 100, 100, 200);

    blackView.backgroundColor=[UIColor blackColor];

    [self.view addSubview:blackView];