import UIKit
import Alamofire
import SwiftyJSON

class MasterViewController: UITableViewController {

var tableTitle = [String]()
var tableBody = [String]()

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    getJSON()

}

func getJSON(){

    Alamofire.request(.GET, "http://announcement.vassy.net/api/AnnouncementAPI/Get/").responseJSON { (Response) -> Void in

        // checking if result has value
        if let value = Response.result.value {

            let json = JSON(value)

            for anItem in json.array! {

                let title: String? = anItem["Title"].stringValue
                let body: String? = anItem["Body"].stringValue
                self.tableTitle.append(title!)
                self.tableBody.append(body!)

            }

        }

    }

    self.tableView.reloadData()

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

// Table View Stuff

override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
    return 1
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return self.tableTitle.count
}


override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as! TableViewCell

    // cell config
    cell.title!.text = tableTitle[indexPath.row]
    cell.body!.text = tableBody[indexPath.row]
    return cell

}

}

func getJSON(){

    Alamofire.request(.GET, "http://announcement.vassy.net/api/AnnouncementAPI/Get/").responseJSON { (Response) -> Void in

        // checking if result has value
        if let value = Response.result.value {

            let json = JSON(value)

            for anItem in json.array! {

                let title: String? = anItem["Title"].stringValue
                let body: String? = anItem["Body"].stringValue
                self.tableTitle.append(title!)
                self.tableBody.append(body!)

            }

            dispatch_async(dispatch_get_main_queue()) {
                self.tableView.reloadData()
            }

        }

    }

}

import AlamofireImage
import SwiftyJSON

class NetworkHandler {

   /// The shared instance to define the singleton.
  static let sharedInstance = RequestManager()


  /**
  Private initializer to create the singleton instance.
  */
  private init() { }

  func getJSON(completionHandler: (json: JSON?, error: NSError?) -> Void) {

      Alamofire.request(.GET, http://announcement.vassy.net/api/AnnouncementAPI/Get/).responseJSON { response in

        switch(response.result) {
        case .Success(let value):

            let json = JSON(value)
            completionHandler(json: json, error: nil)

        case .Failure(let error):
            completionHandler(json: nil, error: error)
        }
    }
  }
}

class MasterViewController: UITableViewController {

   var tableTitle = [String]()
   var tableBody = [String]()

   override func viewDidLoad() {
       super.viewDidLoad()
       // Do any additional setup after loading the view, typically from a nib.

       NetworkHandler.sharedInstance.getJSON { [weak self] (json, error) -> Void in

         // request was made successful
         if error == nil {
            for anItem in json.array! {
               let title: String? = anItem["Title"].stringValue
               let body: String? = anItem["Body"].stringValue
               self.tableTitle.append(title!)
               self.tableBody.append(body!)
            }

            dispatch_async(dispatch_get_main_queue()) {
                self.tableView.reloadData()
            }
         }
       }
    }

    // rest of your code
 }

make func getJSON() to func getJSON(_ whatUwant2execute : @escaping () -> () )

getJSON { ... codes ... }

getJSON(_ whatUwant2execute : @escaping () -> () ) {

Alamofire.request(.GET, "http://announcement.vassy.net/api/AnnouncementAPI/Get/").responseJSON { (Response) -> Void in

    // checking if result has value
    if let value = Response.result.value {

        let json = JSON(value)
        whatUwant2execute()
        .
        .
        .

getJSON ({ ... codes ... })