Reload and not reload if press back from different view controllers. Swift

Question

The top three answers can solve my questions. It is hard to pick which one is the best. So, I just pick the one who is the first to answer my question. Sorry for amateur and iOSEnthusiatic. Thank you for your help. I appreciate it.

ViewController 1 has a table view.

My question is how to reload the table view only if I click back from view controller 2, and not reload the table view if I click back from view controller 3.

Right now, my code for back button is

@IBAction func backButtonTapped(sender: AnyObject) {
    self.dismissViewControllerAnimated(true, completion: nil)
}

In view controller 1. I know that the table view would be reloaded from either view controller 2 or 3

override func viewDidAppear(animated: Bool) {
    loadTable()
}

I tried to put loadTable() in viewDidLoad and try to write the below code for back button in view controller 2. But, it doesn't work.

let storyboard = UIStoryboard(name: "Main", bundle: nil)
let controller = storyboard.instantiateViewControllerWithIdentifier("UserHomePageViewController") as! UserHomePageViewController
controller.viewDidLoad()

Any suggestion what I should do? Thank you for your help.

EDIT:

I think this is an easier way to do it, but it still does not work as I thought. I guess it is because the viewDidAppear is executed before the call of reloadTableBool. Correct? Is there any way to fix it? Thank you. You help would be appreciated.

class 2ViewController
@IBAction func backButtonTapped(sender: AnyObject) {
        let storyboard = UIStoryboard(name: "Main", bundle: nil)
        let controller = storyboard.instantiateViewControllerWithIdentifier("1ViewController") as! 1ViewController
        print("viewcontroller2 before call: \(controller.reloadTableBool)")
        controller.reloadTableBool = false
        print("viewcontroller2 after call: \(controller.reloadTableBool)")
        self.dismissViewControllerAnimated(true, completion: nil)
    }
class 1ViewController
var reloadTableBool = true
override func viewDidAppear(animated: Bool) {
    print("viewcontroller1: \(reloadTableBool)")
    if reloadTableBool == true {
        loadTable()
    }
}

When I click back on view controller 2, it prints

viewcontroller2 before call: true
viewcontroller2 after call: false
viewcontroller1: true

Answer 1

Here is a link to a question I answered a couple days ago. Use the navigation controller delegate to handle the back button. In your second view controller, set the delegate to self and reload the tableview when you press the back button.

override func viewDidLoad() {
    super.viewDidLoad()

    navigationController?.delegate = self
}

func navigationController(navigationController: UINavigationController, willShowViewController viewController: UIViewController, animated: Bool) {
    if let controller = viewController as? FirstViewController {
        controller.tableView.reloadData()
    }
}

NOTE: I'm assuming you're using the back button of the navigation controller here.

EDIT: Another example using your manually added back button:

@IBAction func backButtonTapped(sender: AnyObject) {

    if let viewControllers = app.window?.rootViewController?.childViewControllers {
        viewControllers.forEach { ($0 as? FirstViewController)?.tableView.reloadData() }
    }

    self.dismissViewControllerAnimated(true, completion: nil)
}

Seeing as you are using a navigation controller:

@IBAction func backButtonTapped(sender: AnyObject) {

    navigationController?.viewControllers.forEach { ($0 as? FirstViewController)?.tableView.reloadData() }

    self.dismissViewControllerAnimated(true, completion: nil)
}