How to change height of UIView that already has height anchor?

Question

If I have this for a child view controller:

autoCompleteViewController.view.translatesAutoresizingMaskIntoConstraints = false
        NSLayoutConstraint.act         


        

Answer 1

Additionally to @Mukesh answer is simply updating the constraint:

var heightAnchor:NSLayoutConstraint!

override func viewDidLoad() {
    super.viewDidLoad()
    heightAnchor = autoCompleteViewController.view.heightAnchor.constraint(equalToConstant:44.0)
    heightAnchor.isActive = true
}

func changeMyHeight(numberOfSuggestions: Int) {
    heightAnchor.constant = 44.0 + CGFloat(numberOfSuggestions * 45)
}

Notes:

• You cannot fully declare this variable at the class level, as autoCompleteViewController.view is not yet instantiated.
• You cannot set up the constraint and set isActive = true at the same time. I've always gotten a build error.