Swift navigate back from view2 to view1 - ios

Question

I have View1 in which button has title and I did successful segue to View2 with passing the Button title String which will be assigned to View 2 Button also.
Now when user go back from View2 to View1 , View1 Button has no value. How can I pass button value to View1?
I tried delegate method.. But no success :
Edited
View1
class PatientBreifInfoViewController: UIViewController, TasksViewDelegate {
var passName: String!
#IBOutlet weak var patientName: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
patientName.setTitle(passName, forState: .Normal)
}
func setName(name: String) {
patientName.setTitle(name, forState: .Normal)
print("View1")
print(name)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if (segue.identifier == "toTasks") {
let controller = segue.destinationViewController as! TasksViewController
controller.delegate = self
controller.passName = passName
}
}
}
View2
protocol TasksViewDelegate: class {
func setName(patientName: String)
}
class TasksViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
var passName : String!
#IBOutlet weak var backButton: UIButton!
#IBOutlet weak var tableView: UITableView!
#IBOutlet weak var patientName: UIButton!
weak var delegate: TasksViewDelegate?
override func viewDidLoad() {
super.viewDidLoad()
patientName.setTitle(passName, forState: .Normal)
}
#IBAction func backButton(sender: AnyObject) {
delegate!.setName(passName)
self.navigationController?.popViewControllerAnimated(true)
}
}

Answer 1

Your protocol and delegate should work fine. However, you implementation of setName in ViewController1 is not using the Name parameter passed into it however:
func setName(Name: String)
{
passName = patientName
}
Should be changed to something like:
func setName(Name: String)
{
patientName = Name
}
You should also follow the swift naming convention of variables, parameters and functions starting with lowercase names and types beginning with uppercase names. So should be setName(name: String) not setName(Name: String) which would also mean changing patientName = Name to patientName = name in the example.
Update
Because your view controller will stay in memory while ViewController2 is on screen viewDidLoad will not get called again when transitioning from ViewController2 to ViewController1. Instead, you can set the button's title directly in your delegate method. For example:
func setName(name: String)
{
patientName.setTitle(name, forState: .Normal)
}

Answer 2

popViewController(animated:) removes/pops current view controller from navigation stack. Now you can use first view controller of navigation stack to access its members. You may not need to use delegate here
Try this and see:
class TasksViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
#IBAction func backButton(sender: AnyObject) {
self.navigationController?.popViewControllerAnimated(true)
if let pbiViewController = self.navigationController?.viewControllers.first as? PatientBreifInfoViewController {
pbiViewController.passName = passName
}
}
}
class PatientBreifInfoViewController: UIViewController {
var passName: String?
}