default database <- system-wide feault, language defaults, app-specific defaults NSUserDefaults.standardUserDefaults() -> shared defaults object
key, value
“address” -> “P. Sherman, 42 Wallaby Way, Sydney”
NSUserDefaults.standardUserDefaults().valueForKey(key:String)
stringForKey(key:String), boolForKey(key:String), floatForKey(key:String)
NSUserDefaults.standardUserDefaults().setValue(AnyObject?, key:”keyString”)
import UIKit import Foundation class ViewController: UIViewController { @IBOutlet var mainView: UIView! @IBOutlet weak var midnightThemeLabel: UILabel! @IBOutlet weak var themeSwitch: UISwitch! @IBOutlet weak var titleLabel: UILabel! @IBOutlet weak var imageView: UIImageView! override func viewDidLoad(){ super.viewDidLoad() if let weWantMidnight = NSUserDefaults.standardUserDefaults().valueForKey("midnightThemeOn") { if weWantMidnight as Bool { switchToMidnight() print("we lik midnight") } else { print("we like daylight") } } else { NSUserDefaults.standardUserDefaults().setValue(false, forKey:"midnightThemeOn") print("This is the first launch ever!") } } }