Having problems with saving and loading in Swift 3.0 iOS 10 -

i'm new swift , ios programming scene , trying learn bunch of things. app, want save , load 1 integer, having problems, found on stack overflow , internet doesn't seem work on swift 3. app crashes immediately, breaks on:

@iboutlet weak var staticlabel: uilabel! 

it says "thread 1: breakpoint 3.5" . , tips appreciated :)

import uikit import avfoundation  var player: avaudioplayer? var number = 0  class viewcontroller: uiviewcontroller {     @iboutlet weak var staticlabel: uilabel!     @iboutlet weak var numberlabel: uilabel!     let defaults = userdefaults.standard      override func viewdidload() {         super.viewdidload()         load()     }      func load()     {         number = defaults.integer(forkey: "save")         numberlabel.text = string(number)     }      func playsound()     {         let path = bundle.main.path(forresource: "rightyouare.mp3", oftype: nil)         let url = url(fileurlwithpath: path!)          {             let sound = try avaudioplayer(contentsof: url)             player = sound             sound.play()         }         catch {             // couldn't load file :(         }      }       @ibaction func minus(_ sender: anyobject) {         number = number - 1         numberlabel.text = string(number)         defaults.set(number, forkey: "save")     }      @ibaction func plus(_ sender: uibutton) {         playsound()         number = number + 1         numberlabel.text = string(number)         defaults.set(number, forkey: "save")     } } 

your line of code

number = defaults.integer(forkey: "save") 

user defaults integer key save nil, key not exist @ in user defaults

before load integer user defaults , has set first

 if defaults.object(forkey: "save") !=    nil { number =    defaults.integer(forkey: "save") } 

this make sure object exists in user defaults before getting it's value

finally load function should be

func load()  {     if defaults.object(forkey: "save") != nil      {          number = defaults.integer(forkey: "save")          numberlabel.text = string(number)     }         }