fittingSizeLevel
The priority level with which the view wants to conform to the target size in that computation.
Declaration
static var fittingSizeLevel: UILayoutPriority { get }Discussion
When you send a systemLayoutSizeFitting(_:) message to a view, the size fitting most closely to the target size is computed. This priority is quite low. It’s generally not appropriate to make a constraint at exactly this priority. You want to be higher or lower.