Auto Layout Example: Springs and Structs

Auto Layout Example: Springs and Struts.swift

// A view containing stacked title and message labels
// The labels have flexible width that changes accordingly to this view's size changes

class SomeView: UIView {
  
  let titleLabel: UILabel
  let messageLabel: UILabel
  // ...other subviews
  
  override init(frame: CGRect) {
    let elementsDistance = 20
    
    let titleLabelSize = CGSize(width: frame.size.width - elementsDistance * 2, height: 21) // 21 because it looks good (seriously) 
    let titleLabelX = (frame.size.width - titleLabelSize.width) / 2 // center horizontally
    let titleLabelOrigin = CGPoint(x: titleLabelX, y: elementsDistance)
    let titleLabelFrmae = CGRect(origin: titleLabelOrigin, size: titleLabelSize)
    titleLabel = UILabel(frame: titleLabelFrame)
    titleLabel.autoresizingMask = .flexibleWidth
    
    let messageLabelSize = CGSize(width: frame.size.width - elementsDistance * 2, height: 21) // 21 because it looks good (seriously) 
    let messageLabelX = (frame.size.width - messageLabelSize.width) / 2 // center horizontally
    let messageLabelOrigin = CGPoint(x: titleLabelX, y: titleLabel.frame.maxY + elementsDistance)
    let messageLabelFrmae = CGRect(origin: messageLabelOrigin, size: messageLabelSize)
    messageLabel = UILabel(frame: messageLabelFrame)
    messageLabel.autoresizingMask = .flexibleWidth
  
    // ...and so on for all other elements
    
    super.init(frame: frame)
    addSubview(titleLabel)
    addSubview(messageLabel)
    // ...
  }
  
}