request - Class proper not assigned in swift -

i'm doing practice, , find class property(adnames) can't assigned. can assigned outside(the place comment out). here code:

import uikit import alamofire import swiftyjson  class adtableviewcontroller: uitableviewcontroller {      var adnames: [json]?      override func viewdidload() {         super.viewdidload()          alamofire.request(.get, "http://codewithchris.com/code/afsample.json").responsejson { (response) -> void in              if let value = response.result.value{                  let json = json(value)                 print(json["secondkey"].arrayvalue) //["item1","item2","item3"]                  self.adnames = json["secondkey"].arrayvalue             }         } //        self.adnames = ["item1", "item2", "item3"]     }      override func tableview(tableview: uitableview, numberofrowsinsection section: int) -> int {         if let names = adnames {             return names.count         }         return 0     }      override func tableview(tableview: uitableview, cellforrowatindexpath indexpath: nsindexpath) -> uitableviewcell {         ...     }  } 

can tell me reason? thanks!

your alamofire request runs in background. meanwhile, tableview wants display , calls numberofrowsinsection. time, alamofire has not finished work, adnames hasn't been set.

you need refresh tableview reloaddata() after adnames set. i.e.

    alamofire.request(.get, "http://codewithchris.com/code/afsample.json").responsejson { (response) -> void in         if let value = response.result.value{             let json = json(value)             self.adnames = json["secondkey"].arrayvalue             self.tableview.reloaddata()         }     } 

then tableview refresh , re-call numberofrowsinsection, , @ time, adnames not nil.