使主線程等到URLRequest完成

Question

我試圖執行，直到URLRequest完成。

func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!, withError error: Error!) { 
    self.sendRequest(request: request as URLRequest) { 
     } 
    self.firebaseAuth(credential) 
    self.performSegue(withIdentifier: SEGUE_TO_FIRST_CONTENT_PAGE, sender: nil) 

} 

func sendRequest (request: URLRequest, completion: @escaping() ->()) { 
    let session = URLSession.shared 

    session.dataTask(with: request as URLRequest) { (data, response, error) in 
     UIApplication.shared.isNetworkActivityIndicatorVisible = false 
     do { 
      let userData = try JSONSerialization.jsonObject(with: data!, options:[]) as? [String:AnyObject] 
      let genderData = userData!["gender"] as! String 
      self.userObject.gender = genderData 
      completion() 
     } catch { 
      completion() 
      print("ERROR") 
     } 
     print("sendRequest Done!") 
     }.resume() 
} 

現在，它甚至在完成sendRequest（）之前執行segue。我無法弄清楚如何讓主線程等待直到sendRequest（）完成。

Answer 1

修改完成處理程序將請求傳遞狀態，並基於該status.If在完成處理動作的操作是什麼做的UI，然後包裹在主thread.Sample下面

func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!, withError error: Error!) { 
    self.sendRequest(request: request as URLRequest){ (loginStatus) in 
     if loginStatus { 
      DispatchQueue.main.async { 
      self.firebaseAuth(credential) 
      self.performSegue(withIdentifier: SEGUE_TO_FIRST_CONTENT_PAGE, sender: nil) 
      } 
     } 
     else{ 
      //Handle Error case 
     } 
    } 

} 

func sendRequest (request: URLRequest, completion: @escaping (Bool) ->()) { 
    let session = URLSession.shared 

    session.dataTask(with: request as URLRequest) { (data, response, error) in 
     UIApplication.shared.isNetworkActivityIndicatorVisible = false 
     do { 
      let userData = try JSONSerialization.jsonObject(with: data!, options:[]) as? [String:AnyObject] 
      let genderData = userData!["gender"] as! String 
      self.userObject.gender = genderData 
      completion(true) 
     } catch { 
      completion(false) 
      print("ERROR") 
     } 
     print("sendRequest Done!") 
     }.resume() 
}