imjhk03

// Initialize an array with fixed number of default values
var digitCounts = Array(repeating: 0, count: 5)
// [0, 0, 0, 0, 0]

// Convert an array of integers to an array of strings, use 'map()'
let numbers: [Int] = [1, 2, 3, 4, 5]
let stringArray = numbers.map { String($0) }

// Find the maximum element in an array, can be nil
let numbers = [1, 2, 3, 4, 5]

imjhk03

extension View {
    func hostingView() -> UIView {
        let hostingView = UIHostingController(rootView: self)
        return hostingView.view
    }
}

imjhk03

enum OpenURL {
    enum Scheme {
        case url(String)
        case tel(String)
        case app(String)
    }
    
    static func open(scheme: OpenURL.Scheme, completion: ((Bool) -> Void)? = nil) {
        let application = UIApplication.shared
        let url: URL

imjhk03

class SwipeBackGestureViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        navigationController?.hidesBarsOnSwipe = true
        navigationController?.interactivePopGestureRecognizer?.delegate = self
    }

    override func viewDidAppear(_ animated: Bool) {

imjhk03

1. Using Markup
Single Line comment
//: line of markup content

Multi Line Comment
/*:
  ...
*/

2. Headings

imjhk03

import Foundation

enum Dough: String {
    case basic
    case cheeseCrust
}

enum Topping: String, CaseIterable {
    case pepperoni
    case sausage

imjhk03

import UIKit

protocol Moveable {
    func move(to point: CGPoint)
}

extension Moveable {
    func move(to point: CGPoint = .zero) {
        move(to: point)
    }

imjhk03

func collectionView(_ collectionView: UICollectionView, willDisplaySupplementaryView view: UICollectionReusableView, forElementKind elementKind: String, at indexPath: IndexPath) {
    // works from iOS 12 and below
    view.layer.zPosition = 0
}

imjhk03

import UIKit

enum UIHelper {

    /// Convert Zeplin line height to iOS line spacing
   static func lineSpacing(from lineHeight: CGFloat, font: UIFont) -> CGFloat {
       let value = lineHeight - font.lineHeight
       return value
   }

imjhk03

import Foundation

extension String {
    func toDate(format: String) -> Date? {
        let formatter = DateFormatter()
        formatter.dateFormat = format
        return formatter.date(from: self)
    }
}