ios - 服务器不返回数据时如何停止MBProgressHUD并添加 subview

在我的应用程序中，我有一个此类用于从服务器获取数据:

class Api{

func loadOffers(completion:(([Offers])-> Void), offer_id: String, offerStatus:String){


    let myUrl = NSURL(string: "http://www.myServer.php/api/v1.0/offers.php")
    let request = NSMutableURLRequest(URL: myUrl!)
    request.HTTPMethod = "POST"
    let postString = "offer_id=\(offer_id)&offerStatus=\(dealStatus)&action=show"
    request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)

    let task = NSURLSession.sharedSession().dataTaskWithRequest(request)
        { data, response, error in
            if error != nil {
                println("error\(error)")
            }else{
               var err:NSError?

               let jsonObject : AnyObject! = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil)

                if let dict = jsonObject as? [String: AnyObject] {

                if let myOffers = dict["offers"] as? [AnyObject] {

                var offers = [Offers]()

                for offer in myOffers{

                let offer = Offers(dictionary: offer as! NSDictionary)

                offers.append(offer)

                let priority = DISPATCH_QUEUE_PRIORITY_DEFAULT
                                    dispatch_async(dispatch_get_global_queue(priority, 0 )){
                                                                                   dispatch_async(dispatch_get_main_queue()){

                completion(offers)

                             }
                           }
                        }
                    }
                }
            }
      }
    task.resume()
   }
 }

然后在我的View Controller中加载模型:

    class MyViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {


    var offers: [Offers]!

    func loadModel() {
    let loadingNotification = MBProgressHUD.showHUDAddedTo(self.view, animated: true)
    loadingNotification.mode = MBProgressHUDMode.Indeterminate
    loadingNotification.labelText = "updating your offers..."
    offers = [Offers]()
    let api = Api()
    api.loadOffers(didLoadOffers , offer_id: dealIdent!, offerStatus: "open")

    }

    func didLoadOffers(offers:[Offers]){

    self.offers = offers
    self.tableView.reloadData()
    MBProgressHUD.hideAllHUDsForView(self.view, animated: true)
    self.refreshControl.endRefreshing()
    }

    override func viewWillAppear(animated: Bool) {

    loadModel()

    }
 }

一切正常，除了当JSON字典为空时，这意味着没有提供MBProgressHUD继续旋转。

我想停止在事件指示器中添加一个 subview ，该 subview 表示没有报价。任何建议将不胜感激。

我试过了:
if offers.isEmpty{ MBProgressHUD.hideAllHUDsForView(self.view, animated: true) }
并且
if offers == 0 { MBProgressHUD.hideAllHUDsForView(self.view, animated: true) }
但它不起作用

谢谢

最佳答案

发生这种情况是因为您在主队列中设置了HUD，但正尝试从另一个队列中删除HUD。所有与UI相关的更改均应在main_queue()中完成

尝试使用此代码

dispatch_async(dispatch_get_main_queue(), {

  // your code to modify HUD here

});

关于ios - 服务器不返回数据时如何停止MBProgressHUD并添加 subview ，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/30151270/