Can I call static method from background queue in swift?

Question

I have a static getData() method in the ServerCommunication class can I call this method from background queue.

//ServerCommunication.swift

import UIKit
import Foundation


class ServerCommunication
{
      class func getData(url: String, sessionId: String) -> ServerResponse {
            //server communication code goes here
      }
}

func populateData() {
     DispatchQueue.global(qos: .background).async {
           let response = ServerCommunication.getData(url: URL, sessionId: "")
     }
}

Can anybody explain what will the impact on thread executions Or may I need to define ServerCommunication class as Singleton?

getData() static class executed multiple times when calling from background queue

#Edit1 Some more explanations

This problem occurred when I am trying to open a specific viewController when Push notification occurs. I am using a third party library called FAPanelController which accept a center, left and right viewController respectively.

Code sample:

@available(iOS 10.0, *)
func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
//Now I want to open a viewController
if let panel = self.window?.rootViewController as? FAPanelController     
{
    let centerNavVC = storyboard.instantiateViewController(withIdentifier: "HomeViewController") as! UINavigationController
        let vc = centerNavVC.topViewController as! HomeViewController
        panel.center(centerNavVC, afterThat: {
            //HomeViewController has a method populateData() in viewWillAppear()
        })
}
}

Answer 1

You can use Closures for that

class ServerCommunication
{
    class func getData(url: String, sessionId: String, success: @escaping ((_ responseObject: ServerResponse?) -> Void)) {
        //server communication code goes here
        success(serverData) // serverData is a server response
    }
}

func populateData() {
    ServerCommunication.getData(url: "", sessionId: "", success: { (response) in
       // You can handle response here
       print(response)
    })
}