Pass variable from child view to parent view in Swift -

i'm trying pass variable child view (inputpopup.swift) parent view using setter , getter functions. here code in child view:

var char: string! var buttonpressed = string()  @ibaction func addbuttonpressed(sender: anyobject) {     buttonpressed = "addbutton"     setchar("+")     getchar()     self.removeanimate() }  @ibaction func minusbuttonpressed(sender: anyobject) {     buttonpressed = "minusbutton"     setchar("-")     self.removeanimate() }  @ibaction func dividebuttonpressed(sender: anyobject) {     buttonpressed = "dividebutton"     setchar("/")     self.removeanimate() }  @ibaction func multiplybuttonpressed(sender: anyobject) {     buttonpressed = "multiplybutton"     setchar("*")     self.removeanimate() }  //setter method func setchar(var thischar: string){     char = thischar }  //getter method func getchar()-> string{     if (buttonpressed == "addbutton"){         char = "+"     }     if (buttonpressed == "minusbutton"){         char = "-"     }     if (buttonpressed == "dividebutton"){         char = "/"     }     if (buttonpressed == "multiplybutton"){         char = "*"     }     return char } 

i trying access 'char' variable in parent view so, returning nil - presumably because calling new instance of function.

@ibaction func runbuttonpressed(sender: anyobject) {     inputpopup().getchar() }  

how can pass data child parent effectively?

i update label in parent view, based on button click within child view. trying implement key-value observation. here's i've got far.

class observechar: nsobject {  dynamic var char = string()  func updatechar(){      char = string() } 

}

private var mycontext = 0  class observer: nsobject {  var objecttoobserve = observechar()  override init(){      super.init()      objecttoobserve.addobserver(self, forkeypath: "char", options: .new, context: &mycontext) }  override func observevalueforkeypath(keypath: string, ofobject object: anyobject, change: [nsobject : anyobject], context: unsafemutablepointer<void>) {      if context == &mycontext {          println("char updated: \(change[nskeyvaluechangenewkey])")      } else {         super.observevalueforkeypath(keypath, ofobject: object, change: change, context: context)     } }  deinit {      objecttoobserve.removeobserver(self, forkeypath: "char", context: &mycontext)  } 

}

ok，maybe can set child view property of parent view,maybe

var inputpopview : inputpopup       /**<initialize somewhere */ 

and can use

@ibaction func runbuttonpressed(sender: anyobject) { self.inputpopview.getchar()  }