How to change bottom layout constraint in iOS, Swift

Question

I have scroll view as @IBOutlet

@IBOutlet weak var mainScrollView: UIScrollView!

I want to change the

\"Bottom space to: B         


        

Answer 1

Take the constraint as IBOutlet of NSLayoutConstraint.

Set the constraint outlets and change constant value by :

self.sampleConstraint.constant = 20
self.view.layoutIfNeeded()