ios - Swift - Saving user data using NSKeyedArchiver, getting error on conversion to NSArray -

so have array of custom objects. when try save array nsuserdefaults, have archive them. here doing archive array of custom objects :

override func tableview(tableview: uitableview, numberofrowsinsection section: int) -> int {      //3      var allmessages = defaults.objectforkey(userdefaultsmesssagekey) as! [addmessageviewcontroller.harasstext]     var amessage = addmessageviewcontroller.harasstext(phonenumber: 0, message: "1", frequency: 1, active: 1)     allmessages.append(amessage)     savemessage(allmessages)       return (allmessages.count) }  func archivemessage(message:[addmessageviewcontroller.harasstext]) -> nsdata {     let archivedobject = nskeyedarchiver.archiveddatawithrootobject(message nsarray)     return archivedobject } func savemessage(messages: [addmessageviewcontroller.harasstext]) {     let archivedobject = archivemessage(messages)     defaults.setobject(archivedobject, forkey: userdefaultsmesssagekey)     defaults.synchronize() } func retrievedata()-> [addmessageviewcontroller.harasstext]? {     if let unarchiveobject = nsuserdefaults.standarduserdefaults().objectforkey(userdefaultsmesssagekey) as? nsdata {         return nskeyedunarchiver.unarchiveobjectwithdata(unarchiveobject) as? [addmessageviewcontroller.harasstext]     }     return nil } 

the flow :

1. on savemessage call, pass custom array in archived. here array looks gdb. can see array, , has 1 class object contained in it.

   ([harass_your_kate.addmessageviewcontroller.harasstext]) $r0 = 1 value { [0] = 0x00007fa5ab409600 { objectivec.nsobject = { isa = harass_your_kate.addmessageviewcontroller.harasstext } phonenumber = 0 message = "1" frequency = 1 active = 1 } }

2. the array gets passed archivemessage. code fails on nskeyedarchiver method. error message follows :

   [_ttcc16harass_your_kate24addmessageviewcontroller10harasstext encodewithcoder:]: unrecognized selector sent instance 0x7fa5ab409600 

   2016-07-15 16:31:26.019 harass kate[5858:7847495] * -[nskeyedarchiver dealloc]: warning: nskeyedarchiver deallocated without having had -finishencoding called on it. 2016-07-15 16:31:26.023 harass kate[5858:7847495] * terminating app due uncaught exception 'nsinvalidargumentexception', reason: '-[_ttcc16harass_your_kate24addmessageviewcontroller10harasstext encodewithcoder:]: unrecognized selector sent instance 0x7fa5ab409600

i appreciate of help, thank in advance!

edit: here definition of object:

class text : nsobject {     var phonenumber = 0             //text address send     var message: string = ""        //message sent     var frequency = 24              //number of hours between messages (usually multiple of 24 - 24 = daily)     var active = 0                  // 0 if cancelled, 1 if active      init(phonenumber: int, message: string, frequency: int, active: int ){         self.phonenumber = phonenumber         self.message = message         self.frequency = frequency         self.active = active     } } 

nskeyedarchiver serializes objects taking advantage of methods you have provide conforming nscoding protocol. can't automatically infer how save custom classes; have implement follows:

class text : nsobject, nscoding {     var phonenumber = 0             //text address send     var message: string = ""        //message sent     var frequency = 24              //number of hours between messages (usually multiple of 24 - 24 = daily)     var active = 0                  // 0 if cancelled, 1 if active      init(phonenumber: int, message: string, frequency: int, active: int ){         self.phonenumber = phonenumber         self.message = message         self.frequency = frequency         self.active = active     }      required init?(coder adecoder: nscoder) {         phonenumber = adecoder.decodeinteger(forkey: "phonenumber")         message = adecoder.decodeobject(forkey: "message") as! string         frequency = adecoder.decodeinteger(forkey: "frequency")         active = adecoder.decodeinteger(forkey: "active")     }      func encode(with acoder: nscoder) {         acoder.encode(phonenumber, forkey: "phonenumber")         acoder.encode(message, forkey: "message")         acoder.encode(frequency, forkey: "frequency")         acoder.encode(active, forkey: "active")     } } 

as can see, initializer reads coder , creates , instance, whereas encode method saves relevant information coder. in simple class this, implementations may seem obvious, in more complex custom type, there non-trivial encoding decisions make.