How do I add a placeholder to my UITextField? (Using Xcode 12) - swift

Question

EDIT: New ErrorCurrently using XCode 12, and I'm trying to add a placeholder. I followed the Swift QuestionBot documentation but it doesn't work (I'm assuming it's because my XCode is much newer). Anyway, appreciate all the help!
EDIT: I added an image of a new error I got.
EDIT 2: Added MyQuestionAnswerer() struct! It's on a different view controller (obvious).
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var responseLabel: UILabel!
#IBOutlet weak var askButton: UIButton!
#IBOutlet weak var questionField: UITextField!
let questionAnswerer = MyQuestionAnswerer()
override func viewDidLoad() {
super.viewDidLoad()
questionField.becomeFirstResponder()
}
func respondToQuestion(_ question: String) {
let answer = questionAnswerer.responseTo(question: question)
displayAnswerTextOnScreen(answer)
questionField.placeholder = "Ask another question..."
questionField.text = nil
askButton.isEnabled = false
}
#IBAction func askButtonTapped(_ sender: AnyObject) {
guard questionField.text != nil else {
return
}
questionField.resignFirstResponder()
}
func displayAnswerTextOnScreen(_ answer: String) {
responseLabel.text = answer
}
}
extension ViewController: UITextFieldDelegate {
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return false
}
func textFieldDidEndEditing(_ textField: UITextField) {
guard let text = textField.text else {
return
}
respondToQuestion(text)
}
#IBAction func editingChanged(_ textField: UITextField) {
guard let text = textField.text else {
askButton.isEnabled = false
return
}
askButton.isEnabled = !text.isEmpty
}
}
struct MyQuestionAnswerer {
func responseTo(question: String) -> String {
let loweredQuestion = question.lowercased()
if loweredQuestion == "What is the current vaccination rate of the Philippines?" {
return "As of August 8, the vaccination rate of the Philippines is 10%!"
} else if loweredQuestion.hasPrefix("Where") {
return "Check the map for nearby vaccination centers."
}
}

Answer 1

The placeholder is not present when the textFiled as it is not set until the respondToQuestion method is called. It should probably be set inside of a view controller life cycle method such as viewDidLoad().
Example:
override func viewDidLoad() {
super.viewDidLoad()
questionField.placeholder = "Ask another question"
questionField.becomeFirstResponder()
}