I wrote my first Swift program tonight. It simply puts a button on the screen and handles the click event. Everything is done in code. Code on Github: https://github.com/melling/swift/tree/master/CenteredAutoLayoutButton
The relevant functions are here:
func addButton() { centeredButton = UIButton() centeredButton.setTitle("Am I centered?", forState: .Normal) centeredButton.setTitleColor(UIColor.blueColor(), forState: .Normal) centeredButton.setTranslatesAutoresizingMaskIntoConstraints(false) centeredButton.addTarget(self, action: "pressed:", forControlEvents: .TouchUpInside) self.view.addSubview(centeredButton) var viewDictionary:Dictionary = ["centeredButton": centeredButton] let horizontal:[AnyObject]! = NSLayoutConstraint.constraintsWithVisualFormat("H:|-50-[centeredButton]-50-|", options: NSLayoutFormatOptions(0), metrics: nil, views: viewDictionary) let vertical:[AnyObject]! = NSLayoutConstraint.constraintsWithVisualFormat("V:|-100-[centeredButton]-100-|", options: NSLayoutFormatOptions(0), metrics: nil, views: viewDictionary) self.view.addConstraints(horizontal) self.view.addConstraints(vertical) } func pressed(sender: UIButton!) { var alertView = UIAlertView(); alertView.addButtonWithTitle("Ok"); alertView.title = "My Title"; alertView.message = "Congratulations"; alertView.show(); }