Generic UIViewController with horizontal UIScrollView that was created programatically with Auto Layout using SnapKit

ViewController.swift

//
//  ViewController.swift
//  HorizontalScrollView
//
//  Created by Jörn Schoppe on 13.04.16.
//  Copyright © 2016 pixeldock. All rights reserved.
//

import UIKit
import SnapKit

class ViewController: UIViewController {
    
    let scrollView = UIScrollView()
    let subViews = [UIView(), UIView(), UIView(), UIView()]
    let colors = [UIColor.greenColor(), UIColor.blueColor(), UIColor.redColor(), UIColor.orangeColor()]

    override func viewDidLoad() {
        super.viewDidLoad()
        
        view.addSubview(scrollView)
        scrollView.snp_makeConstraints { (make) in
            make.edges.equalTo(view)
        }
        
        subViews.enumerate().forEach { index, subview in
            subview.backgroundColor = colors[index]
            scrollView.addSubview(subview)
            subview.snp_makeConstraints(closure: { (make) in
                make.top.equalTo(0)
                make.size.equalTo(scrollView)
                switch index {
                case 0:
                    make.left.equalTo(0)
                case subViews.count - 1:
                    make.left.equalTo(subViews[index - 1].snp_right)
                    make.right.equalTo(0)
                default:
                    make.left.equalTo(subViews[index - 1].snp_right)
                }
            })
        }
    }
}

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