SampleViewController

class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        addSquareToView(size: CGSizeMake(30, 30), color: UIColor.greenColor());
    }

    func addSquareToView(size s: CGSize, color: UIColor) {
        var square: UIView;
        let frame = CGRectMake(10, 10, s.width, s.height);
        
        // This is equivalent to [[UIView alloc] initWithFrame:frame]
        square = UIView(frame: frame);
        square.backgroundColor = color;
        self.view.addSubview(square);
    }
}