Typing animation: deleting characters

Question

Here\'s a typing animation that adds up characters from an Array to the text of a text field at a fixed time interval:

@IBOutlet weak var textFieldMain: UITextFi         


        

Answer 1

I would rewrite the deleteLetter() method into something like this:

func deleteLetter() {
    myString = myString.substringToIndex(myString.endIndex.predecessor())
    textFieldMain.text = myString

    typingAnimationTimer?.invalidate()
    if myString.characters.count > 0 {
        typingAnimationTimer = NSTimer.scheduledTimerWithTimeInterval(0.05, target: self, selector: "deleteLetter", userInfo: nil, repeats: false)
    }
}

Edit: Looks like Zoltan already beat me to it.

Answer 2

Why not do the following:

func deleteLetter() {
    if textFieldMain.text != "" {
        textFieldMain.text = str.substringToIndex(textFieldMain.text.endIndex.predecessor())
    } else {
       typingAnimationTimer?.invalidate()
    }
}

By the way, if you start your timer with "repeats: true" in fireDeletionTimer() you don't need to recreate it again and again in deleteLetter()

Also, stringByReplacingOccurrencesOfString() clears every instance of that letter in your text, not just the last one.