Typewriter effect text animation

Question

I\'m trying to create a typewriter animation effect with a UILabel, but can\'t find any answers. Is the UILabel the correct object to use? I want the text to print to the sc

Answer 1

Based on this Answer: Letter by letter animation for UILabel?

I've updated it to Swift 4 and solved the CPU animation problem with DispatchWorkItem in order to create a queue.

Swift 4

extension UILabel {
    func setTextWithTypeAnimation(typedText: String, characterDelay: TimeInterval = 5.0) {
        text = ""
        var writingTask: DispatchWorkItem?
        writingTask = DispatchWorkItem { [weak weakSelf = self] in
            for character in typedText {
                DispatchQueue.main.async {
                    weakSelf?.text!.append(character)
                }
                Thread.sleep(forTimeInterval: characterDelay/100)
            }
        }

        if let task = writingTask {
            let queue = DispatchQueue(label: "typespeed", qos: DispatchQoS.userInteractive)
            queue.asyncAfter(deadline: .now() + 0.05, execute: task)
        }
    }

}

Usage

label.setTextWithTypeAnimation(typedText: text, characterDelay:  10) //less delay is faster