README.md

Margins

No Margins

//
//  ViewController.swift
//  LayoutMargins
//
//  Created by Jonathan Rasmusson (Contractor) on 2018-09-10.
//  Copyright © 2018 Jonathan Rasmusson (Contractor). All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        setupViews()
    }

    func setupViews() {
        let label = UILabel()
        label.translatesAutoresizingMaskIntoConstraints = false
        label.text = "Hello"
        label.backgroundColor = .green

        let stack = UIStackView()
        stack.translatesAutoresizingMaskIntoConstraints = false
        stack.addArrangedSubview(label)

        view.addSubview(stack)

	// constraints
        stack.topAnchor.constraint(equalTo:view.topAnchor).isActive = true
        stack.leadingAnchor.constraint(equalTo:view.leadingAnchor).isActive = true
        stack.trailingAnchor.constraint(equalTo:view.trailingAnchor).isActive = true
        stack.bottomAnchor.constraint(equalTo:view.bottomAnchor).isActive = true
    }

}

safeAreaLayoutGuide

In iOS11 Apple deprecated the top and bottom layout guides and replaced them with the Safe Area layout guides.

        let margins = view.safeAreaLayoutGuide
        stack.topAnchor.constraint(equalTo: margins.topAnchor).isActive = true
        stack.leadingAnchor.constraint(equalTo: margins.leadingAnchor).isActive = true
        stack.trailingAnchor.constraint(equalTo: margins.trailingAnchor).isActive = true
        stack.bottomAnchor.constraint(equalTo: margins.bottomAnchor).isActive = true

//
//  ViewController.swift
//  LayoutMargins
//
//  Created by Jonathan Rasmusson (Contractor) on 2018-09-10.
//  Copyright © 2018 Jonathan Rasmusson (Contractor). All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        setupViews()
    }

    func setupViews() {
        let label = UILabel()
        label.translatesAutoresizingMaskIntoConstraints = false
        label.text = "Hello"
        label.backgroundColor = .green

        let stack = UIStackView()
        stack.translatesAutoresizingMaskIntoConstraints = false
        stack.addArrangedSubview(label)

        view.addSubview(stack)

        view.directionalLayoutMargins = NSDirectionalEdgeInsets(top: 100, leading: 8, bottom: 100, trailing: 8) // iOS 11

        let margins = view.safeAreaLayoutGuide

        stack.topAnchor.constraint(equalTo: margins.topAnchor).isActive = true
        stack.leadingAnchor.constraint(equalTo: margins.leadingAnchor).isActive = true
        stack.trailingAnchor.constraint(equalTo: margins.trailingAnchor).isActive = true
        stack.bottomAnchor.constraint(equalTo: margins.bottomAnchor).isActive = true
    }

}

I believe the recommended approach now from Apple is to do everything via view.directionalLayoutMargins. So don't even use or refer to view.layoutMargins. Just set and work padding via the directional way on your view, and go from there.

Layout & Directional margins

The layoutMargins property was deprecated on iOS 11 and replaced with directionalLayoutMargins to take into account the current language direction. We still use layoutMarginsGuide when styling, but we set it via directionalLayoutMargins which translates the CGFloats into the proper anchors under the hood.

So if you need to set specific insets on a view do it like this.

//
//  ViewController.swift
//  LayoutMargins
//
//  Created by Jonathan Rasmusson (Contractor) on 2018-09-10.
//  Copyright © 2018 Jonathan Rasmusson (Contractor). All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        setupViews()
    }

    func setupViews() {
        let label = UILabel()
        label.translatesAutoresizingMaskIntoConstraints = false
        label.text = "Hello"
        label.backgroundColor = .green

        let stack = UIStackView()
        stack.translatesAutoresizingMaskIntoConstraints = false
        stack.addArrangedSubview(label)

        view.addSubview(stack)

        view.directionalLayoutMargins = NSDirectionalEdgeInsets(top: 100, leading: 8, bottom: 100, trailing: 8) // iOS 11

        let margins = view.layoutMarginsGuide

        stack.topAnchor.constraint(equalTo: margins.topAnchor).isActive = true
        stack.leadingAnchor.constraint(equalTo: margins.leadingAnchor).isActive = true
        stack.trailingAnchor.constraint(equalTo: margins.trailingAnchor).isActive = true
        stack.bottomAnchor.constraint(equalTo: margins.bottomAnchor).isActive = true
    }

}

Summary

So do everything via topAnchor, leadingAnchor, trailingAnchor, bottomAnchor. Just vary the layout guide you are using (layoutMarginsGuide or safeAreaLayoutGuide and adjust via directionalLayoutMargins.

        view.directionalLayoutMargins = NSDirectionalEdgeInsets(top: 100, leading: 8, bottom: 100, trailing: 8) // iOS 11
	
	let margins = view.safeAreaLayoutGuide
        let margins = view.layoutMarginsGuide

        stack.topAnchor.constraint(equalTo: margins.topAnchor).isActive = true
        stack.leadingAnchor.constraint(equalTo: margins.leadingAnchor).isActive = true
        stack.trailingAnchor.constraint(equalTo: margins.trailingAnchor).isActive = true
        stack.bottomAnchor.constraint(equalTo: margins.bottomAnchor).isActive = true

Also remember to protect yourself against non iOS 11 versions.

	if #available(iOS 11, *) {
	    imageView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor).isActive = true
	} else {
	    imageView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
	}

Links that help

• Apple layout margins
• Apple directionalLayoutMargins
• Apple safe area
• Use your load safe area guide