owningView
The view that owns this layout guide.
Declaration
weak var owningView: NSView? { get set }Discussion
By default, this property is nil. To participate in Auto Layout, the layout guide must be added to a view by calling its addLayoutGuide(_:) method. Do not modify this property directly. Instead, use the view’s addLayoutGuide(_:) and removeLayoutGuide(_:) methods, which update this property as necessary.