ExpandableLabel.swift

final class ExpandableLabel: UILabel {
    
    private let collapsedHeight: CGFloat = 65
    private var heightConstraint: NSLayoutConstraint!
            
    override func awakeFromNib() {
        super.awakeFromNib()
        heightConstraint = NSLayoutConstraint(item: self, attribute: .height, relatedBy: .equal, toItem: nil,
                                              attribute: .height, multiplier: 1, constant: collapsedHeight)
        NSLayoutConstraint.activate([heightConstraint])
        numberOfLines = 0
        contentMode = .top
        isUserInteractionEnabled = true
        addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(toggle)))
    }
    
    @objc private func toggle() {
        if heightConstraint.constant > collapsedHeight {
            heightConstraint.constant = collapsedHeight
        } else {
            heightConstraint.constant = sizeThatFits(CGSize(width: frame.size.width,
                                                            height: CGFloat.greatestFiniteMagnitude)).height
        }
        UIView.animate(withDuration: 0.25, animations: {
            self.superview?.superview?.superview?.superview?.layoutIfNeeded()
        })
    }
}