How to display UILabel one line at a time in Swift - ios

Question

I have a UILabel in a tableView cell that I would like to animate line by line. The string has line breaks with \n and lines.count returns 7 as expected but no line is being added to the label at all even though the string itself is not nil.
Code in cellForRow
var index = 0
let lines = messageList[indexPath.row].message.components(separatedBy: "\n")
senderCell.otherUserMessage.numberOfLines = lines.count
Timer.scheduledTimer(withTimeInterval: 3, repeats: true, block: { [weak self] timer in
if index != lines.count {
let char = lines[index]
let nChar = "\n\(char)"
senderCell.otherUserMessage.text! += nChar
print("char is \(nChar)") //nChar prints the proper text
print("senderCellText is \(senderCell.otherUserMessage.text!)") // but this prints an array of numbers
// Play sound each time
do {
self!.audioPlayer = try AVAudioPlayer(contentsOf: self!.koalaMessageSound)
self!.audioPlayer.play()
}catch{
// couldn't load file :(
}
index += 1
} else {
timer.invalidate()
}
})
Idea/Expected Result

Answer 1

Only way I found to animate a Label like this was to:
1. create a copy of Label for each line you have in your original Label (calculating frame.height / lineHeight)
2. mask each of those copies with rectangles for single line
3. animate each Label separately - each Label will be displaying one line only there so you can control them separately.
Note: Using \n is impossible, because sometimes text may go to next line due to it's length on smaller devices, so to get real count of lines, you need to calculate like like I described on point 1.