Why is my prepareForSegue code activating the wrong button? - swift

Question

I'm learning how to program and am playing with a Swift project in Xcode. The main storyboard has two view controllers. The first view controller is simply called ViewController and the second view controller is called HelpScreenViewController.
In ViewController I have a "help" button that switches the user to HelpScreenViewController. This button uses a segue called "goToHelpScreenSegue".
In HelpScreenViewController I have three buttons:
"Close" button to dismisses the view (no segue used)
"Send Feedback" button to generate a new email in the Mail app (no segue used)
"Reset Game" button to call a function that is coded within the first ViewController. This third button uses a segue called "resetGameSegue".
What I'm trying to do is...
...Get the "Reset Game" button on the HelpScreenViewController to reset the game by calling a function that's coded within the first view controller.*
To try and get this to work the way I want, I've used the following code:
WITHIN first main ViewController
import UIKit
import iAd
import AdSupport
import AVFoundation //audio
import GameplayKit
class ViewController: UIViewController, ADBannerViewDelegate, MyResetGameProtocol {
#IBOutlet weak var Banner: ADBannerView!
#IBOutlet weak var buttonA: UIButton!
#IBOutlet weak var buttonB: UIButton!
#IBOutlet weak var buttonC: UIButton!
#IBOutlet weak var buttonD: UIButton!
#IBOutlet weak var labelQuestion: UILabel!
#IBOutlet weak var labelScore: UILabel!
#IBOutlet weak var labelTotalQuestionsAsked: UILabel!
#IBOutlet weak var labelFeedback: UILabel!
#IBOutlet weak var buttonNext: UIButton!
var score :Int! = 0
var totalquestionsasked :Int! = 0
var allEntries : NSArray!
var shuffledQuestions: [AnyObject]!
var nextQuestion = -1
var currentCorrectAnswerIndex : Int = 0
var audioPlayer = AVAudioPlayer()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
self.Banner?.delegate = self
self.Banner?.hidden = true
LoadAllQuestionsAndAnswers()
if #available(iOS 9.0, *) {
shuffledQuestions = GKRandomSource.sharedRandom().arrayByShufflingObjectsInArray(allEntries as [AnyObject])
nextQuestion++
LoadQuestion(nextQuestion)
// Fallback on earlier versions
}else{
let randomNumber = Int(arc4random_uniform(UInt32(allEntries.count)))
LoadQuestionPreiOS9(randomNumber)
}
LoadScore()
AdjustInterface()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
let viewController = segue.destinationViewController as! HelpScreenViewController
viewController.controller = self
}
func ResetGame() {
PlaySoundReset()
score = 0
totalquestionsasked = 0
SaveScore()
LoadScore()
}
func PlaySoundReset()
{
let alertSound = NSURL(fileURLWithPath: NSBundle.mainBundle().pathForResource("pcbeep", ofType: "wav")!)
do {
audioPlayer = try AVAudioPlayer(contentsOfURL: alertSound)
} catch {
}
audioPlayer.prepareToPlay()
audioPlayer.play()
}
func SaveScore()
{
let defaults = NSUserDefaults.standardUserDefaults()
defaults.setInteger(score, forKey: "Score")
defaults.setInteger(totalquestionsasked, forKey: "Out of")
}
func LoadScore()
{
let defaults = NSUserDefaults.standardUserDefaults()
score = defaults.integerForKey("Score")
totalquestionsasked = defaults.integerForKey("Out of")
labelScore.text = "Score: \(score)"
labelTotalQuestionsAsked.text = "out of \(totalquestionsasked)"
}
and so on....
WITHIN the second HelpScreenViewController
import UIKit
protocol MyResetGameProtocol {
func ResetGame()
}
class HelpScreenViewController: UIViewController, MyResetGameProtocol {
var controller: MyResetGameProtocol? // reference to the delegate alias First Controller
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
#IBAction func SendFeedback(sender: AnyObject) {
UIApplication.sharedApplication().openURL(NSURL(string: "mailto:feedback#felice.ws?")!)
}
#IBAction func DismissView(sender: AnyObject) {
self.dismissViewControllerAnimated(true, completion: nil) }
#IBAction func buttonResetGame(sender: AnyObject) {
controller.ResetGame()
}
}
Now, at the moment with the above code what happens is that if the user taps the "help" button in the first main ViewController (i.e. goToHelpScreenSegue), not only does it take the user to the help screen, but it also calls the function I want activated when the user taps on the "Reset Game" button instead. That is, at the moment, it's the "help" button that resets the game before taking the user to the help screen.
Now, within the help screen, the first two buttons work normally (but they're not using segues). Tapping on the third button (the Reset Game one) simply returns the user back to the main screen. It doesn't call the function, doesn't reset the game.
I've lost count of the times I've changed the code around to try and get it to work right, but I've obviously missed something really obvious.
In particular, I've tried using the following code instead within the main ViewController:
override func prepareForSegue(segue: UIStoryboardSegue?, sender: AnyObject?) {
if segue?.identifier == "resetGameSegue" {
let viewController = segue!.destinationViewController as! HelpScreenViewController
viewController.controller = self
}
However, this results in nothing happening. What I mean is that the button on the main screen works properly (taking the user to the help screen and not incorrectly calling the resetGame function). And, within the help screen the first two buttons work as expected, but the "Reset Game" button just returns the user to the first screen but without calling the ResetGame function.
I also tried removing the IBActions from both my code and the connections inspector for the "Reset Game" button, but that made no difference either.
Any assistance would be most appreciated as I'm just not getting it! :(

Answer 1

I'm agree with MikeG, that you should probably learn about how delegates should be implemented. But the thing you're doing wrong inside this code is that you're not actually calling ResetGame() function on your delegate. Try to implement your #IBAction function in this way:
#IBAction func buttonResetGame(sender: AnyObject) {
controller?.ResetGame()
}
And yeah, if I understand your logic correctly your HelpScreenViewController should not implement MyResetGameProtocol cause your ViewController is the one who's implementing it.