Visual String Demo

//
//  ViewController.swift
//  LearnVisualString
//
//  Created by Thieu Mao on 12/5/16.
//  Copyright © 2016 thieumao. All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
    }

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)

        let newView = UIView()
        newView.backgroundColor = UIColor.red
        self.view.addSubview(newView)

        newView.translatesAutoresizingMaskIntoConstraints = false

        let views = ["nv" : newView]
        let metrics = ["margins" : 20]

        let vContraints = NSLayoutConstraint.constraints(withVisualFormat: "V:|-(margins)-[nv]-(margins)-|", options: NSLayoutFormatOptions(rawValue: 0), metrics: metrics, views: views)
        let hContraints = NSLayoutConstraint.constraints(withVisualFormat: "H:|-(margins)-[nv]-(margins)-|", options: NSLayoutFormatOptions(rawValue: 0), metrics: metrics, views: views)

        self.view.addConstraints(vContraints)
        self.view.addConstraints(hContraints)

    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


}