How to make a custom view resize with the window with Cocoa Auto Layout?

Question

I have a single window with a single custom view in it, and I want the custom view to resize with the window so that it entirely fills it at any time. If I write:

Answer 1

You can create constraints with Layout Anchors with very easy to read format:

Swift2 code

func fit(childView: UIView, parentView: UIView) {
    childView.translatesAutoresizingMaskIntoConstraints = false
    childView.topAnchor.constraintEqualToAnchor(parentView.topAnchor).active = true
    childView.leadingAnchor.constraintEqualToAnchor(parentView.leadingAnchor).active = true
    childView.trailingAnchor.constraintEqualToAnchor(parentView.trailingAnchor).active = true
    childView.bottomAnchor.constraintEqualToAnchor(parentView.bottomAnchor).active = true
}

Use:

parrentView.addSubview(childView)
fit(childView, parentView: parrentView)