How to set a title depending of which button we click. Send data

Question

I have been looking for my answer but everything seems a little bit confusing, so I decided to try to ask the following question:

I have three buttons in a first view.

Red , blue, and white.

And a hidden Label in this first one view too, which changes depending of the button clicked (and it appears when a button is clicked with text "red/blue/white button selected").

Also, when a button is touched, a new button does appear with a text "next screen" to push a segue to another view with a label in the title.

Question is: how to set the title in the new view depending of which button we tapped in the first VC?

I mean, if we have clicked red the tittle would be: "We have clicked red button" . Etc

Code :

@IBOutlet weak var labelTipo: UILabel!
@IBOutlet weak var siguiente: UIButton!

var redSel = String()
var BlueSel = String()
var whiteSel = String()

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    siguiente.hidden = true

    redSel = labelTipo.text!
    BlueSel = labelTipo.text!
    whiteSel = labelTipo.text!
}

@IBAction func redButton(sender: AnyObject) {
    siguiente.hidden = false

    labelTipo.text = "Has elegido un regalo de cumpleaños"
}

@IBAction func blueButton(sender: AnyObject) {
     siguiente.hidden = false

    labelTipo.text = "Has elegido un regalo de aniversario"
}

@IBAction func whiteButton(sender: AnyObject) {
     siguiente.hidden = false

    labelTipo.text = "Has elegido un regalo casual"
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if(segue.identifier == "detailViewController") {
        print("Colour is")

        let vc = segue.destinationViewController as! detailViewController

        vc.blueSel = BlueSel
        vc.redSel = redSel
        vc.whiteSel = whiteSel
    }
}
}

class ViewController: UIViewController {

var redSel = String()
var blueSel = String()
var whiteSel = String()

@IBOutlet weak var titleLabel: UILabel!

override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.

    titleLabel.text = ""
}

Answer 1

You can do this a lot more succinctly with a little though. Here is a complete example which you can download from https://bitbucket.org/abizern/so-32935054/get/1ec75832723d.zip

If you set an enum for the types of selection you can configure the UI when setting the values.

This is the complete main view controller

import UIKit

class ViewController: UIViewController {

    enum Selection: String {
        case NoSelection = ""
        case RedButton = "Has elegido un regalo de cumpleaños"
        case BlueButton = "Has elegido un regalo de aniversario"
        case WhiteButton = "Has elegido un regalo casual"
    }

    @IBOutlet var colorLabel: UILabel!
    @IBOutlet var nextButton: UIButton!

    var selection: Selection = .NoSelection {
        didSet {
            colorLabel.text = selection.rawValue
            if selection == .NoSelection {
                nextButton.hidden = true
            } else {
                nextButton.hidden = false
            }
        }
    }


    override func viewDidLoad() {
        super.viewDidLoad()
        colorLabel.text = selection.rawValue
        nextButton.hidden = true
    }

    @IBAction func onRed(sender: UIButton) {
        selection = .RedButton
    }

    @IBAction func onBlue(sender: UIButton) {
        selection = .BlueButton
    }

    @IBAction func onWhite(sender: UIButton) {
        selection = .WhiteButton
    }


    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        guard
            segue.identifier == "ShowDetail",
            let destinationVC = segue.destinationViewController as? DetailViewController
            else { return }

        destinationVC.displayText = selection.rawValue
    }
}

In the segue you pass the string to the destination view controller:

import UIKit

class DetailViewController: UIViewController {

    @IBOutlet var label: UILabel!

    var displayText: String = ""


    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)
        label.text = displayText
    }

}

This is less code and a bit more elegant IMHO. The UI is configured by setting the selection, you don't have to manually set the button's hidden variable in each function.

Answer 2

It is very simple, Please create a local variable to assign the string when you click in the button. And pass this variable to another viewController, where you are pushing it to. In your case assign the value of "labelTipo.text" to a new variable and pass it to another viewController.

// Your SourceViewController

@IBOutlet weak var labelTipo: UILabel!
@IBOutlet weak var siguiente: UIButton!

    var passThisValue = String()

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    siguiente.hidden = true

}

@IBAction func redButton(sender: AnyObject) {
    siguiente.hidden = false

    labelTipo.text = "Has elegido un regalo de cumpleaños"
    self.passThisValue = labelTipo.text 

}

@IBAction func blueButton(sender: AnyObject) {
     siguiente.hidden = false

    labelTipo.text = "Has elegido un regalo de aniversario"
    self.passThisValue = labelTipo.text 

}

@IBAction func whiteButton(sender: AnyObject) {
     siguiente.hidden = false

    labelTipo.text = "Has elegido un regalo casual"

    self.passThisValue = labelTipo.text 
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if(segue.identifier == "AnotherViewController") {

        let vc = segue.destinationViewController as! AnotherViewController

        vc.valueFromSourceViewController = self.passThisValue
    }
}
}

// Your AnotherViewController 

class AnotherViewController: UIViewController {

var valueFromSourceViewController = String()

@IBOutlet weak var titleLabel: UILabel!

override func viewDidLoad() {
    super.viewDidLoad()

    titleLabel.text = self.valueFromSourceViewController
}

Answer 3

Try to make some adds in your prepareForSegue method but make labelTipo variable as property of your class:

    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if(segue.identifier == "detailViewController") {
            print("Colour is")

            let vc = segue.destinationViewController as! detailViewController

            vc.blueSel = BlueSel
            vc.redSel = redSel
            vc.whiteSel = whiteSel
//make some newLocalVariable property in vc! 
            vc.newLocalVariable = self.labelTipo.text
        }
    }

So actually you saves in local variable "newLocalVariable" of your "vc" new value which is equals to labelTipo.text for example or whatever you want.