Question

我在我的应用程序的一部分中有这段代码：

let myUrl = NSURL(string: "http://aesolutions.ddns.net/data/load_tasks_calendar.php");
let request = NSMutableURLRequest(url: myUrl! as URL);
request.httpMethod = "POST";
let postString = "id_class=\(UserDefaults.standard.string(forKey: "userClass")!)";
request.httpBody = postString.data(using: String.Encoding.utf8);
MenuViewController.tasksCalendarArray.removeAll()                             
let task = URLSession.shared.dataTask(with: request as URLRequest){
     data, response, error in                            
     if error != nil{
          print("error1=\(String(describing: error))")
          return
     }                            
     var _: NSError?                           
     do{
          let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as? NSArray                          
          if let parseJSON: NSArray = json {                    
               for index in 0...parseJSON.count-1 {                         
                    if (parseJSON[index] is NSNull){
                         MenuViewController.tasksCalendarArray.removeAll()
                    }else{                         
                         let compito = parseJSON[index] as! [String:Any]                        
                         let task = tasks.init(taskId: compito["id"] as! String,taskType: compito["type"] as! String,taskSubject: compito["subject"] as! String,taskDate: compito["date"] as! String,taskComment: compito["comment"] as! String)                          
                         MenuViewController.tasksCalendarArray.append(task)                           
                    }
               }                          
          }
     }catch{
          print("error2=\(error)")
          return
     }
     DispatchQueue.main.async(execute:  {
          self.performSegue(withIdentifier: "loginToDiary", sender: self)
     });                              
}
task.resume();

我想在加载所有数组时才执行segue。我怎么能等到json终止或正确完成？因为我注意到有时它是正确的，有时它执行segue，因此数组是空的，然后在应用程序中有错误。有人可以帮我添加一个带有“加载消息”的警报来等待阵列加载吗？

等到JSON调用完成

0 个答案: