Swift - Characters in text field are not visible - swift

Question

In my application I have several custom designed games to practice spelling and grammar. The whole process was working just fine until iOS 11 released.
An overview of how my application works:
the game receives a random word and picture from our server and automatically creates a stack of text fields (in a horizontal stack view)
the amount of text fields is similar to the amount of letters of the received word (e.g. the word "throw" would create five text fields next to each other)
the view is linked to a custom keyboard that is displayed until all questions are answered correctly
the text fields reset themselves if the user's input is not similar to the expected answer
The problem since iOS 11
Only the first two questions don't show the user's input in their respective text fields (the first letter always seem to work). The console also confirms that the input and the comparison of the letters does indeed work, but the text fields stay empty all the time. The game even resets perfectly and goes to the next question if the word has been answered correctly. The weird thing is that question 3, 4 and 5 do not have this problem.
In the example below you can see what is going on. The first question ("plant") only shows the first letter. The second question ("clap") does the same thing. The third question ("bite") does not have this problem. My custom cursor works just fine and automatically jumps to the next box.
Swift Code (functionality only)
let TEXT_FIELD_TAG = 1000
let CURSOR_INDEX = 0
var game: GameDictionary? {
didSet {
self.m_Client.GetMediaImage(game?.Image) { (image) in
self.imageView.image = image
}
self.selectedIndex = 0
self.answerChars = (game?.Content?.map { String($0).lowercased() })!
self.views = (0..<self.answerChars.count).map { _ in UITextField() }
var index: NSInteger = TEXT_FIELD_TAG
for textField in self.views {
textField.backgroundColor = .white
textField.textColor = Constants.MAIN_THEME_COLOR
textField.font = UIFont(name: Constants.GAME_FONT_TYPE_1, size: scaledFontSize(fontSize: 36))
textField.textAlignment = .center
textField.delegate = self
textField.layer.cornerRadius = 10
textField.autocapitalizationType = .none
textField.tag = index
textField.isUserInteractionEnabled = true
// Create the cursor object and animate the blinking
let cursor = UIView(frame: CGRect(x: scaledViewSize(viewSize: 10), y: scaledViewSize(viewSize: 10), width: 2, height: scaledViewSize(viewSize: 30)))
cursor.backgroundColor = Constants.MAIN_THEME_COLOR
cursor.isHidden = true
UIView.animate(withDuration: 1, delay: 0, options: .repeat, animations: {() -> Void in
cursor.alpha = 0
}, completion: {(_ animated: Bool) -> Void in
cursor.alpha = 1
}
)
textField.addSubview(cursor)
self.container.addArrangedSubview(textField)
index+=1
}
}
}
// MARK: Question handlers
override func prepareForReuse() {
super.prepareForReuse()
inputArray.removeAll()
answerChars.removeAll()
self.selectedIndex = 0
for view in self.views {
view.removeFromSuperview()
}
self.views.removeAll()
}
override func onFocus() {
self.resetCursorTextField()
keyboardLauncher.onKeyPressed = { character in
self.views[self.selectedIndex].text = character
self.textChanged(sender: self.views[self.selectedIndex])
}
keyboardLauncher.showKeyboard()
keyboardLauncher.enableKeyboard()
}
func resetCursorTextField() {
for (index, textfield) in self.views.enumerated() {
textfield.subviews[CURSOR_INDEX].isHidden = (index == 0) ? false : true
}
}
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
guard let text = textField.text else { return true }
let newLength = text.count + string.count - range.length
return newLength <= 1
}
func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
return false
}
func resetInputViews() {
inputArray.removeAll()
self.selectedIndex = 0
self.resetCursorTextField()
for tag in TEXT_FIELD_TAG...(TEXT_FIELD_TAG + (self.answerChars.count) - 1) {
let textField = self.container.viewWithTag(tag) as! UITextField!
textField?.text = ""
if (tag == TEXT_FIELD_TAG) {
textField?.becomeFirstResponder()
}
}
}
func textChanged(sender: UITextField) {
if (sender.text?.count)! > 0 {
inputArray.append((sender.text?.lowercased())!)
if self.answerChars[self.selectedIndex] != inputArray.last! {
self.delegate?.updateAnswer(inputArray.joined(), false)
self.resetInputViews()
} else {
self.selectedIndex+=1
let nextField = sender.superview?.viewWithTag(sender.tag + 1) as! UITextField!
nextField?.becomeFirstResponder()
sender.subviews[CURSOR_INDEX].isHidden = true
nextField?.subviews[CURSOR_INDEX].isHidden = false
if self.answerChars.count == inputArray.count {
playCorrectAnswer()
isCompleted = true
keyboardLauncher.disableKeyboard()
self.textField?.isEnabled = false
self.delegate?.updateAnswer(inputArray.joined(), true)
self.delegate?.nextQuestion(self)
}
}
}
}
CellForItemAtIndexpath
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
if indexPath.item == self.m_Collection?.count {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: gameScoreOverviewCell, for: indexPath) as! GameScoreOverviewCell
cell.closeViewButton.addTarget(self, action: #selector(closeView(sender:)), for: .touchUpInside)
cell.rulesButton.addTarget(self, action: #selector(handleAlertScoreOverview(sender:)), for: .touchUpInside)
return cell
}
let game = self.m_Collection![indexPath.item]
if game.StarryGrade == StarryGrade.Grade4 && game.Level == Level.Level1 {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: fourthGradeCellLevel1, for: indexPath) as! GameCellFourthGradeLevel1
cell.cancelButton.addTarget(self, action: #selector(closeViewWithAlert(sender:)), for: .touchUpInside)
cell.questionLabel.text = "Question \(indexPath.item + 1) of \(self.m_Collection!.count)"
cell.game = game
cell.delegate = self
keyBoardIsVisible = true
return cell
}
}

Answer 1

This may not be a programmatic issue, but an interface issue. Try the following:
Ensure that you are compiling the app for Debug
Recreate the scenario in the left image below, where you have typed some letters and they are hidden:
Click this button in the Debug Navigator:
Select View UI Hierarchy.
In the deconstruction of your UI in Xcode, click on a text field that contains a hidden character.
You should now check a few things:
in the Object Inspector in the right panel, check to make sure that the Text Field's Title attribute is the character you typed (if not, the Text Field isn't capturing the keyboard input)
also in the Object Inspector, make sure that the View Visibility attribute is set to Not Hidden
in the Size Inspector (also in the right panel), check to make sure that the Text Field is big enough to show the character
I've had a similar issue before, and these steps allowed me to determine the cause of the problem. I hope this helps.