类型的价值＆＃39; DispatchQueue＆＃39;没有会员＆＃39;异步＆＃39; - 斯威夫特3

Question

我刚刚将xcode8更新为Swift 3并收到此错误：

Value of type 'DispatchQueue' has no member 'asynchronously'

在这一行：

   DispatchQueue.main.asynchronously(execute:

以下是整个代码段：

  DispatchQueue.main.asynchronously(execute: {

                        //Display alert message with confirmation
                        let myAlert = UIAlertController(title: "Alert", message:messageToDisplay, preferredStyle: UIAlertControllerStyle.Alert);




                        let okAction = UIAlertAction(title:"OK", style:UIAlertActionStyle.Default){

                            action in self.dismissViewControllerAnimated(true, completion:nil);

                        }

                        myAlert.addAction(okAction)
                        self.presentViewController(myAlert, animated:true, completion:nil);
                    });
                }
            }
            catch let error as NSError {
                print(error.localizedDescription)
            }

        }

        task.resume()

}
}

最近更新到Swift 3给了我很多错误，它们会自动修复，但是这个不会自行解决，我不知道该怎么办。

Answer 1

在Swift 3和iOS 10的生产版本中，没有asynchronously方法。这只是async：

DispatchQueue.main.async {
    //Display alert message with confirmation
    let alert = UIAlertController(title: "Alert", message: messageToDisplay, preferredStyle: .alert)

    let okAction = UIAlertAction(title: "OK", style: .default) { action in
        self.dismiss(animated: true)
    }

    alert.addAction(okAction)
    self.present(alert, animated: true)
}