斯威夫特不改变变量

Question

我目前正在从https://www.simplifiedios.net/swift-php-mysql-tutorial/修改本教程。该程序的目的是在收到正确的消息时关闭ViewController，如果收到无效的消息则显示UIAltertAction。可能会有一些我错过的东西＆＃34; notChangingVariable＆＃34;永远不会改变？

    ...IBACTION...
    var notChangingVariable: Int

    notChangingVariable = 0
    ...othervariablesdeclared...
    let task = URLSession.shared.dataTask(with: request as URLRequest){
        data, response, error in
        if(error != nil){
            return;
        }

        //parsing the response
        do{
            //converting resonse to NSDictionary
            let myJSON =  try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as? NSDictionary
            //parsing the json
            if let parseJSON = myJSON{
                var msg : String!
                //getting the json response
                msg = parseJSON["message"] as! String?
                if(msg == "SameTeam"){
                    print(msg)
                    notChangingVariable  = 1
                    print(notChangingVariable)
                }
            }
        }catch{
            print("error32 is \(error)")
        }
    }
    task.resume()
    print(notChangingVariable) //IS 0

    ...FURTHER USE notChangingVariable...