SnapKit/Sources/LayoutConstraintItem.swift

94 lines
2.9 KiB
Swift

//
// SnapKit
//
// Copyright (c) 2011-Present SnapKit Team - https://github.com/SnapKit
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#if canImport(UIKit)
import UIKit
#else
import AppKit
#endif
public protocol LayoutConstraintItem: AnyObject {
}
@available(iOS 9.0, OSX 10.11, *)
extension ConstraintLayoutGuide : LayoutConstraintItem {
}
extension ConstraintView : LayoutConstraintItem {
}
extension LayoutConstraintItem {
internal func prepare() {
if let view = self as? ConstraintView {
view.translatesAutoresizingMaskIntoConstraints = false
}
}
internal var superview: ConstraintView? {
if let view = self as? ConstraintView {
return view.superview
}
if #available(iOS 9.0, OSX 10.11, *), let guide = self as? ConstraintLayoutGuide {
return guide.owningView
}
return nil
}
internal var constraints: [Constraint] {
return self.constraintsSet.allObjects as! [Constraint]
}
internal func add(constraints: [Constraint]) {
let constraintsSet = self.constraintsSet
for constraint in constraints {
constraintsSet.add(constraint)
}
}
internal func remove(constraints: [Constraint]) {
let constraintsSet = self.constraintsSet
for constraint in constraints {
constraintsSet.remove(constraint)
}
}
private var constraintsSet: NSMutableSet {
let constraintsSet: NSMutableSet
if let existing = objc_getAssociatedObject(self, &constraintsKey) as? NSMutableSet {
constraintsSet = existing
} else {
constraintsSet = NSMutableSet()
objc_setAssociatedObject(self, &constraintsKey, constraintsSet, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
}
return constraintsSet
}
}
private var constraintsKey: UInt8 = 0