Do action on JSON complete

Question

I have written a function that makes a JSON request and puts the result in three arrays.

I want to present a view controller after this JSON request is completed fully.

I tried putting the action below the for-in loop, but this didn't work.

This is my code:

func getJSON() {
        var vc = self.storyboard?.instantiateViewControllerWithIdentifier("myVCId") as ViewController
        let urlAsString = "http://localhost:8888/domainchecker/check.php?domain=/" + tfDomain.text;
        println(urlAsString);
        let url = NSURL(string: urlAsString)!
        let urlSession = NSURLSession.sharedSession()
        
        let jsonQuery = urlSession.dataTaskWithURL(url, completionHandler: { data, response, error -> Void in
            if (error != nil) {
                println(error.localizedDescription)
            }
            var err: NSError?
            
            var jsonResult = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: &err) as NSDictionary
            if (err != nil) {
                println("JSON Error \(err!.localizedDescription)")
            }
            let arrayFromJson: [[String:String]] = jsonResult["ITEMS"] as [[String:String]]
            dispatch_async(dispatch_get_main_queue(), {
                for item in arrayFromJson {
                    vc.tableData.append(item["DOMAIN"]!);
                    vc.tablePrice.append(item["PRICE"]!);
                    vc.tableAvailability.append(item["AVAILABLE"]!);
                }
                self.presentViewController(vc, animated: true, completion: nil)
            })
            
        })
        jsonQuery.resume()
    }

This is the action I want to do after the code has completed:

self.presentViewController(vc, animated: true, completion: nil)

Answer 1

if (arrayFromJson.count > 0) {
                    self.presentViewController(vc, animated: true, completion: nil)
                }

this is it.