labelConstraints.swift

func labelConstraints() {
  // Center button in Page View
  NSLayoutConstraint(
    item: label,
    attribute: .CenterX,
    relatedBy: .Equal,
    toItem: view,
    attribute: .CenterX,
    multiplier: 1.0,
    constant: 0.0)
    .active = true
  
  // Set Width to be 80% of the Page View Width
  NSLayoutConstraint(
    item: label,
    attribute: .Width,
    relatedBy: .Equal,
    toItem: view,
    attribute: .Width,
    multiplier: 0.8,
    constant: 0.0)
    .active = true
  
  // Set Y Position Relative to Bottom of Page View
  NSLayoutConstraint(
    item: label,
    attribute: .CenterY,
    relatedBy: .Equal,
    toItem: view,
    attribute: .CenterY,
    multiplier: 1.0,
    constant: 0.0)
    .active = true
}