iosswiftuialertviewuialertviewdelegate

How to add action to buttons in Alert in Swift


I am beginner level programmer. I am trying to add action to buttons on Alert, but it doesn't work. I just want to test if the alert button choice can change the text in label, but it doesn't work. Of course I can see the alert and buttons well, but nothing happens after clicking the button.

@IBOutlet var statusLabelAlert : UILabel

var alertTest = UIAlertView()

@IBAction func alertButton(sender : AnyObject) {

    alertTest.message = "Select one!"
    alertTest.addButtonWithTitle("1st")
    alertTest.addButtonWithTitle("2nd")
    alertTest.addButtonWithTitle("3rd")
    alertTest.title = "Test Alert"
    alertTest.show()

}
func alertView(alertView: UIAlertView!, clickedButtonAtIndex buttonIndex: Int){
    switch buttonIndex{
    case 0:
        statusLabelAlert.text = "1st"
    case 1:
        statusLabelAlert.text = "2nd"
    case 2:
        statusLabelAlert.text = "3rd"
    default:
        statusLabelAlert.text = "error"
    }

}

Solution

  • Is your clickedButtonAtIndex method calling? Put a breakpoint and debug the code. You doesn't set the delegate of alertView.

    @IBOutlet var statusLabelAlert : UILabel
    
    var alertTest = UIAlertView()
    alertTest.delegate = self   //set the delegate of alertView
    
    @IBAction func alertButton(sender : AnyObject) {
    
    alertTest.message = "Select one!"
    alertTest.addButtonWithTitle("1st")
    alertTest.addButtonWithTitle("2nd")
    alertTest.addButtonWithTitle("3rd")
    alertTest.title = "Test Alert"
    alertTest.show()
    
    }
    func alertView(alertView: UIAlertView!, clickedButtonAtIndex buttonIndex: Int){
    switch buttonIndex{
    case 0:
        statusLabelAlert.text = "1st"
    case 1:
        statusLabelAlert.text = "2nd"
    case 2:
        statusLabelAlert.text = "3rd"
    default:
        statusLabelAlert.text = "error"
    }
    
    }