A swift vertical layout alternative

gistfile1.swift

//
//  Layout.swift
//
//  Created by Stijn Willems on 10/06/15.
//  Copyright (c) 2015 dooZ. All rights reserved.
//

import Foundation


typealias LeftRigth = (left:UIView, right: UIView?, aspectRatioToViewController: CGFloat?)

class Layout {
	
	typealias Container = (container:UIView, left:UIView, right: UIView?, aspectRatioToViewController: CGFloat?)

	//MARK: - Vertical layout
	
	class vertical {
		class func fitInViewController(viewController: UIViewController, views: [LeftRigth]) {
			
			var viewsWithContainer = [Container]()
			
			for view in views {
				let container = UIView.newAutoLayoutView()
				viewsWithContainer.append((container:container, left: view.left, right: view.right, aspectRatioToViewController: view.aspectRatioToViewController))
			}
			
			addViewAndPinBottomAndTopToViewController(viewController, views:viewsWithContainer)
			addViewsAndPinBottomAndTopToView(viewsWithContainer)
			pinLeftRightAndDimensionToContainer(viewsWithContainer)
		}
		
		private class func pinLeftRightAndDimensionToContainer(views:[Container]){
			
			for view in views {
				view.left.autoPinEdge(.Trailing, toEdge: .Leading, ofView: view.right)
				view.left.autoPinEdge(.Leading, toEdge: .Leading, ofView: view.container)
				view.right?.autoPinEdge(.Trailing, toEdge: .Trailing, ofView: view.container)
				view.left.autoMatchDimension(.Width, toDimension: .Width, ofView: view.container, withMultiplier: 0.2)
			}
		}
		
		private class func addViewsAndPinBottomAndTopToView(views: [Container]){
			for view in views {
				view.container.addSubview(view.left)
				if let right = view.right {
					view.container.addSubview(right)
				}
				view.left.autoPinEdge(.Top, toEdge: .Top, ofView: view.container)
				view.left.autoPinEdge(.Bottom, toEdge: .Bottom, ofView: view.container)
				view.right?.autoPinEdge(.Top, toEdge: .Top, ofView: view.container)
				view.right?.autoPinEdge(.Bottom, toEdge: .Bottom, ofView: view.container)
			}
		}
		
		private class func addViewAndPinBottomAndTopToViewController(viewController: UIViewController, views: [Container]){
			for view in views {
				view.container.setTranslatesAutoresizingMaskIntoConstraints(false)
				viewController.view.addSubview(view.container)
				view.container.autoPinEdge(.Leading, toEdge: .Leading, ofView: viewController.view)
				view.container.autoPinEdge(.Trailing, toEdge: .Trailing, ofView: viewController.view)
			}
			
			let firstContainer = views.first!.container
			let lastContainer = views.last!.container
			var middleViews = views.filter{$0.container != firstContainer}
			
			firstContainer.autoPinToTopLayoutGuideOfViewController(viewController, withInset: 0)
			
			if let multiplier = views.first?.aspectRatioToViewController {
				firstContainer.autoMatchDimension(.Height, toDimension: .Height, ofView: viewController.view, withMultiplier: multiplier)
			}
			
			lastContainer.autoPinToBottomLayoutGuideOfViewController(viewController, withInset: 0)
			
			var previousView = firstContainer
			for view in middleViews {
				view.container.autoPinEdge(.Top, toEdge: .Bottom, ofView: previousView)
				if let multiplier = view.aspectRatioToViewController {
					view.container.autoMatchDimension(.Height, toDimension: .Height, ofView: viewController.view, withMultiplier: multiplier)
				}
				previousView = view.container
			}
		}
	}
	
}