Multi line label in Sprite Kit in Swift

SKMultilineLabel.swift

//
//  SKMultilineLabel.swift
//
//  Created by Craig on 10/04/2015.
//  Copyright (c) 2015 Interactive Coconut. All rights reserved.
//
/*   USE:

(most component parameters have defaults)

let multiLabel = SKMultilineLabel(text: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.", labelWidth: 250, pos: CGPoint(x: size.width / 2, y: size.height / 2))
self.addChild(multiLabel)

*/

import SpriteKit

class SKMultilineLabel: SKNode {
    //props
    var labelWidth:Int {didSet {update()}}
    var labelHeight:Int = 0
    var text:String {didSet {update()}}
    var fontName:String {didSet {update()}}
    var fontSize:CGFloat {didSet {update()}}
    var pos:CGPoint {didSet {update()}}
    var fontColor:SKColor {didSet {update()}}
    var leading:Int {didSet {update()}}
    var alignment:SKLabelHorizontalAlignmentMode {didSet {update()}}
    var dontUpdate = false
    var shouldShowBorder:Bool = false {didSet {update()}}
    //display objects
    var rect:SKShapeNode?
    var labels:[SKLabelNode] = []
    
    init(text:String, labelWidth:Int, pos:CGPoint, fontName:String="ChalkboardSE-Regular",fontSize:CGFloat=10,fontColor:SKColor=SKColor.blackColor(),leading:Int=10, alignment:SKLabelHorizontalAlignmentMode = .Center, shouldShowBorder:Bool = false)
    {
        self.text = text
        self.labelWidth = labelWidth
        self.pos = pos
        self.fontName = fontName
        self.fontSize = fontSize
        self.fontColor = fontColor
        self.leading = leading
        self.shouldShowBorder = shouldShowBorder
        self.alignment = alignment
        
        super.init()
        
        self.update()
    }
    
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    //if you want to change properties without updating the text field,
    //  set dontUpdate to false and call the update method manually.
    func update() {
        if (dontUpdate) {return}
        if (labels.count>0) {
            for label in labels {
                label.removeFromParent()
            }
            labels = []
        }
        let separators = NSCharacterSet.whitespaceAndNewlineCharacterSet()
        let words = text.componentsSeparatedByCharactersInSet(separators)
        
        var finalLine = false
        var wordCount = -1
        var lineCount = 0
        while (!finalLine) {
            lineCount++
            var lineLength = CGFloat(0)
            var lineString = ""
            var lineStringBeforeAddingWord = ""
            
            // creation of the SKLabelNode itself
            let label = SKLabelNode(fontNamed: fontName)
            // name each label node so you can animate it if u wish
            label.name = "line\(lineCount)"
            label.horizontalAlignmentMode = alignment
            label.fontSize = fontSize
            label.fontColor = SKColor.whiteColor()
            
            while lineLength < CGFloat(labelWidth)
            {
                wordCount++
                if wordCount > words.count-1
                {
                    //label.text = "\(lineString) \(words[wordCount])"
                    finalLine = true
                    break
                }
                else
                {
                    lineStringBeforeAddingWord = lineString
                    lineString = "\(lineString) \(words[wordCount])"
                    label.text = lineString
                    lineLength = label.frame.size.width
                }
            }
            if lineLength > 0 {
                wordCount--
                if (!finalLine) {
                    lineString = lineStringBeforeAddingWord
                }
                label.text = lineString
                var linePos = pos
                if (alignment == .Left) {
                    linePos.x -= CGFloat(labelWidth / 2)
                } else if (alignment == .Right) {
                    linePos.x += CGFloat(labelWidth / 2)
                }
                linePos.y += CGFloat(-leading * lineCount)
                label.position = CGPointMake( linePos.x , linePos.y )
                self.addChild(label)
                labels.append(label)
                //println("was \(lineLength), now \(label.width)")
            }
            
        }
        labelHeight = lineCount * leading
        showBorder()
    }
    
    func showBorder() {
        if (!shouldShowBorder) {return}
        if let rect = self.rect {
            self.removeChildrenInArray([rect])
        }
        self.rect = SKShapeNode(rectOfSize: CGSize(width: labelWidth, height: labelHeight))
        if let rect = self.rect {
            rect.strokeColor = SKColor.whiteColor()
            rect.lineWidth = 1
            rect.position = CGPoint(x: pos.x, y: pos.y - (CGFloat(labelHeight) / 2.0))
            self.addChild(rect)
        }
    }
}

Since my usage needed to obey line breaks \n, I updated the code with a few simple changes.
https://gist.github.com/klappy/8cd81068f066b6e36f44

Nice snippet!
However, your game will freeze and run out of memory if you have a word longer than the label width, since it will keep creating empty labels forever. I've added a break condition to line 106,

            if (!finalLine) {
                if lineStringBeforeAddingWord == "" {
                    print("Words don't fit! Decrease the font size of increase the labelWidth (\"\(lineString)\")")
                    break
                }
                lineString = lineStringBeforeAddingWord
            }

Also, updated syntax of debugging line 119,

            print("was \(lineLength), now \(label.frame.size.width)")

Another issue I foresee is that this logic doesn't apply to languages such as Japanese, where there are no spaces between words. I guess for Japanese the only solution would be adding a character one by one, or artificially add spaces to the text at strategic points.

There is an issue with this....

The lines are above each others.

@iiMshl ... There's a var called "leading" when you first create the node. I've found that setting it to the font size seems to do the trick.

@endavid: Thanks for pointing out the issue that would be encountered with words exceeding the line.

As far as the Japanese and other languages that need broken up by something other than spaces, tokenization is a fun subject that would address the issue. I don't have the time right now to jump into tokenization in swift but I have done extensive work in tokenization for many languages in other programming languages such as ruby and javascript. One overly simplistic approach is splitting on posix based non unicode word character classes. In JavaScript I use the XRegexp library that adds unicode support to JS. The regex I commonly use for tokenization is splitting on XRegexp('[^\\pL\\pM]+?') Japanese and other Asian languages sometimes require a dictionary approach to tokenization. Hope that is helpful.

@endavid, but now I don't see any text at all. Every text is bigger than width of the label.