Swift: What instance of my class is in the view - ios

Question

I'm building an app with a container view holding a tableView controller. I create this tableView, but I don't know how to access this object again so I can call function on it. Currently there is a BucketTableViewController object being created automatically (maybe from the storyboard). Then later I want to call a function on it and create another BucketTableViewController object. I can verify they are unique with print statement on that method. How do I set a variable for an object that is the original object?
import UIKit
class FirstViewController: UIViewController {
var bigArray = ["M", "A", "R", "C"]
let delegate = UIApplication.sharedApplication().delegate as! AppDelegate
override func viewDidLoad() {
super.viewDidLoad()
reachForWebsite()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func reachForWebsite(){
let url = NSURL(...)
let task = NSURLSession.sharedSession().dataTaskWithURL(url!) {(data, response, error) in
do {
...
// HERE IS THE ISSUE
var bucketsVC = BucketTableViewController()
bucketsVC.updateBuckets(self.bigArray)
} catch let myJSONError {
print(myJSONError)
}
}
task!.resume()
}
}

Answer 1

You can grab a reference to it from prepareForSeque(_:sender:) in the view controller that owns the container. Make sure that identifier matches the name of the identifier you've set on the segue from the storyboard in Interface Builder. Or you can omit the identifier part if you know for certain that there are no other segues with destination's of type BucketTableViewController.
class BucketTableViewController: UITableViewController {}
class FirstViewController: UIViewController {
var bucketViewController: BucketTableViewController!
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
super.prepareForSegue( segue, sender: sender )
if let vc = segue.destinationViewController as? BucketTableViewController where segue.identifier == "embeddedBuketViewcontroller" {
self.bucketViewController = vc
}
}
}

Answer 2

A comment is too tight for this, so I'm making it an answer. You can make bucketsVC` an instance variable:
class FirstViewController: UIViewController {
var bucketsVS : BucketTableViewController?
func reachForWebsite(){
...
do {
self.bucketsVC = BucketTableViewController()
self.bucketsVC!.updateBuckets(self.bigArray)
} catch {
...
}
// Now you can use it anywhere within your UIViewController
}
}