Why is Optional(“Text”) - Swift

Question

I just started with Swift. So I created a simple application with a label, button and a text field. When you click the button, the app has to change the label with the text

Answer 1

I solved this problem with this for Swift 3;

self.label.text = "\(transaction.amount!)"

Answer 2

Just add an ! exclamation mark to textField.text like following:

@IBAction func updateButton(sender: UIButton) {
    textLabel.text = "Hi \(textField.text!) "
}

Answer 3

One more way can be to use Guard to check if it is not nil.

guard let nameText = textField.text else {
    print("break if nil")
    return
}
textLabel.text = "Hi \(nameText!)" 

Using guard makes sure your app fails early if the condition fails.

Answer 4

So the problem here is that the textField's text is an optional, that you have to unwrap for using it.

Just add an ! to textField.text like this:

textLabel.text = "Hi \(textField.text!)"

Your output will now be Hi TextOfTextField

---

You have a few safer options to unwrap your optionals:

1. nil coalescing operator: ??
   This will use either textField.text, or, if that's nil, use the other value provided, "?" in this case

   textLabel.text = "Hi \(textField.text ?? "?")"
   

2. if let statement:
   Note that this will only update your text field's text, if it's not nil. You could provide an else statement to deal with that.

   if let text = textField.text {
       textField.text = "Hi \(text)"
   }
   

3. guard let statement:
   This works similarly like the if let statement, except that your function will end after the statement.

   guard let text = textField.text else { return }
   textField.text = "Hi \(text)"
   

---

Hope this helps :)

Answer 5

The text of your textField is an optional value because a text field can sometimes be empty. So, use an if let to unwrap the variable and make sure it's not nil — otherwise your program could crash:

if let text: String = textField.text {
   textLabel.text = text
}

Answer 6

In my case for Swift 4.x, I unwrapped by using below command for option Int? values or Optional list cont:

\(topics?.count ?? 0 )