A simple function to make buttons programmatically in swift

buttons.swift

// MARK: - Storyboard Connections
  @IBOutlet weak var letterContainer: UIView! // the UIView that will contain the buttons
    
// ... stuff

//  MARK: Place method call in ViewDidLoad
   func makeButtons(content: [String], margin: CGFloat, bottom: CGFloat) {
        for i in 0...content.count-1 {
            let button: UIButton = UIButton(type: UIButtonType.System)
            button.setTitle(content[i], forState: UIControlState.Normal)
            // button.setBackgroundImage(UIImage(named: "BlueButton"), forState: UIControlState.Normal)
            button.titleLabel?.font = UIFont.systemFontOfSize(12)
            button.setTitleColor(UIColor.whiteColor(), forState: UIControlState.Normal)
            
            // Add buttons to container
            letterContainer.addSubview(button)
            
            // Disable Autoresizing constraints
            button.translatesAutoresizingMaskIntoConstraints = false
            let space: CGFloat = 50.0 + margin
            let left: CGFloat = -60.0 + space * CGFloat(i)
            
            // Auto Layout Rules
            let leftEdge = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.LeadingMargin, relatedBy: NSLayoutRelation.Equal, toItem: letterContainer, attribute: NSLayoutAttribute.LeadingMargin, multiplier: 1.0, constant: left)
            let bottomConstraint = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.Bottom, relatedBy: NSLayoutRelation.Equal, toItem: letterContainer, attribute: NSLayoutAttribute.BottomMargin, multiplier: 1.0, constant: bottom)
            
            let heightConstraint = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.Height, relatedBy: NSLayoutRelation.Equal, toItem: nil, attribute: NSLayoutAttribute.NotAnAttribute, multiplier: 1, constant: 40)
            
            let widthConstraint  = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.Width, relatedBy: NSLayoutRelation.Equal, toItem: nil, attribute: NSLayoutAttribute.NotAnAttribute, multiplier: 1, constant: 50)
            
            // Add all constraints
            letterContainer.addConstraints([leftEdge, bottomConstraint, heightConstraint, widthConstraint])
        }
    }