setupConstraintsViewAndAnimate

setupConstraintsViewAndAnimate

func setupConstraintsViewAndAnimate() {
    constraintsView.backgroundColor = .purple
    self.view.addSubview(constraintsView)

    constraintsView.translatesAutoresizingMaskIntoConstraints = false
    var topConstraint = constraintsView.topAnchor.constraint(equalTo: self.view.topAnchor)
    let widthConstraint = constraintsView.widthAnchor.constraint(equalToConstant: 200)
    let heightConstraint = constraintsView.heightAnchor.constraint(equalToConstant: 200)
    NSLayoutConstraint.activate([
        topConstraint,
        widthConstraint,
        heightConstraint
    ])

    NSLayoutConstraint.deactivate([
        topConstraint
    ])

    let newConstraint = constraintsView.topAnchor.constraint(
        equalTo: self.view.topAnchor,
        constant: 400)

    NSLayoutConstraint.activate([
        newConstraint
    ])

    UIView.animate(withDuration: 0.5) {
        topConstraint = newConstraint
        self.view.layoutIfNeeded()
    }
}