How to make a button an IBOutlet and IBAction in swift

Question

I have a button which I want to disable when my timer ends in Xcode but to disable to button it needs to be an outlet. However, I need it to be an action because it's an important button.

Code:

import UIKit

class ViewController: UIViewController {

    var count = 0
    var timer = 60
    var highScore = 0

    @IBOutlet weak var output: UILabel!
    @IBOutlet weak var timerText: UILabel!
    @IBOutlet weak var scoreText: UILabel!
    @IBOutlet weak var highscoreText: UILabel!

    @IBAction func buttonOne(_ sender: Any) {
        count += 1
        output.text = String(count)
    }

    @IBAction func StartButton(_ sender: Any) {
        Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: Selector(("updateCounting")), userInfo: nil, repeats: true)
    }

    @objc func updateCounting(){
        if timer > 0 {
        timer -= 1
        timerText.text = String(timer)
        } else {
            buttonOneOutlet.isEnabled = false
            timerText.text = "Time up!"
            scoreText.text = "Score: " + String(count)
            if count > highScore {
                highScore = count
                highscoreText.text = String(count)
            } else {
                highscoreText.text = String(highScore)
            }
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    }


}

@oscarF123- Please read and follow below links 1. https://stackoverflow.com/questions/32572305/iboutlet-and-ibaction-in-swift 2. https://www.hackingwithswift.com/read/2/5/from-outlets-to-actions-creating-an-ibaction — Devendra Agnihotri, Aug 04 '19 at 12:34
The button can have both an `@IBAction` _and_ an `@IBOutlet`.] — Rob, Aug 04 '19 at 15:46

score 2 · Answer 1 · answered Aug 04 '19 at 12:47

I think you made some confusion between IBOutlet and IBAction.

Actually here is the difference:

"You need to specify IBAction for methods that will be used in Interface Builder and IBOutlet for objects that will be used in Interface Builder"

(Source - StackOverflow)

I changed your code a little, starting from buttonOneOutlet (IBOutlet) and buttonOne (IBAction).

I added an IBOutlet called buttonOne and I renamed your IBActions like buttonOneTouched and startButtonTouched. Here you can find some documentation about naming conventions in Swift.

Moreover I added a variable called timerObject, so that you can keep a reference to the running timer and invalidate() it later. Otherwise the timer would be running forever.

Here is the updated code:

import UIKit
class ViewController: UIViewController {

    var count = 0
    var timer = 60
    var highScore = 0
    // new timer object declared here
    var timerObject = Timer()

    // new IBOutlet object declared here
    @IBOutlet weak var buttonOne: UIButton!
    @IBOutlet weak var output: UILabel!
    @IBOutlet weak var timerText: UILabel!
    @IBOutlet weak var scoreText: UILabel!
    @IBOutlet weak var highscoreText: UILabel!

    // renamed the function to 'buttonOneTouched' (it was 'buttonOne')
    @IBAction func buttonOneTouched(_ sender: Any) {
        count += 1
        output.text = String(count)
    }

    // renamed the function to 'startButtonTouched' (it was 'StartButton')
    @IBAction func startButtonTouched(_ sender: Any) {
        timerObject = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: Selector(("updateCounting")), userInfo: nil, repeats: true)
    }

    @objc func updateCounting() {
        if timer > 0 {
            timer -= 1
            timerText.text = String(timer)
        } else {
            // added step to invalidate the running timer loop
            timerObject.invalidate()
            // replaced 'buttonOneOutlet' with 'buttonOne'
            buttonOne.isEnabled = false
            timerText.text = "Time up!"
            scoreText.text = "Score: " + String(count)
            if count > highScore {
                highScore = count
                highscoreText.text = String(count)
            } else {
                highscoreText.text = String(highScore)
            }
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    }
}

score 0 · Answer 2 · answered Aug 04 '19 at 12:35

0

You can do it in the same way as you are doing for those Labels

Define the button in your ViewController.

@IBOutlet weak var buttonOneOutlet: UIButton!

Set the IBOutlet from your Storyboard to that button, by control drag.

Hope it helps

answered Aug 04 '19 at 12:35

Bhavin Kansagara

2,866
1
16
20

But I also need the button to be an action? – OscarF123 Aug 04 '19 at 12:38
Yes, You can set both the things, IBOutlet will give it identity and IBAction on touch up inside, will give it action. – Bhavin Kansagara Aug 04 '19 at 12:39
but then I get a thread 1: SIGABRT error (aka. Unconnected or something wrong with outlets or actions) – OscarF123 Aug 04 '19 at 12:41
Try setting the Outlets and Action again for all variables, and may it fix. – Bhavin Kansagara Aug 04 '19 at 12:43

score 0 · Answer 3 · answered Aug 04 '19 at 12:47

Here are the steps you can follow-

For @IBOutlet

1.Declare Your Interface builder Element property just after class name as you already declared for UIlabel

class ViewController: UIViewController{
    @IBOutlet weak var btnTest : UIButton! //Your Interface builder Element

2.Hook the IB Element From Storyboard

For @IBAction

1.Write A method inside your class(say SomeViewController)

@IBAction func didTapTestBtn(_sender : AnyObject){
//write your code here.
}

2.Hook the method from Storyboard.

How to make a button an IBOutlet and IBAction in swift

3 Answers3