Adaptive font fits to height of UILabel, UITextView

AdaptiveFont.swift

// Inspired from
// http://stackoverflow.com/a/26221732/2438676
// http://derekneely.com/tag/resize-text/
// http://stackoverflow.com/a/27115350/2438676

import UIKit

extension UIFont {
    
    class func adaptiveFontWithName(fontName: String, label: UILabel, minSize: CGFloat = 9, maxSize: CGFloat = 999) -> UIFont! {
        var tempFont: UIFont
        var tempMax: CGFloat = maxSize
        var tempMin: CGFloat = minSize

        while (ceil(tempMin) != ceil(tempMax)) {
            let testedSize = (tempMax + tempMin) / 2
            tempFont = UIFont(name:fontName, size:testedSize)!
            
            let paragraphStyle = NSMutableParagraphStyle()
            paragraphStyle.hyphenationFactor = 1.0
            let attributedString = NSAttributedString(string: label.text!, attributes: [NSFontAttributeName: tempFont, NSParagraphStyleAttributeName: paragraphStyle])
            let textFrame = attributedString.boundingRectWithSize(CGSize(width: label.bounds.size.width, height: CGFloat.max), options: NSStringDrawingOptions.UsesLineFragmentOrigin , context: nil)
            
            let difference = label.frame.height - textFrame.height
            
            // print("\(tempMin)-\(tempMax) - tested : \(testedSize) --> difference : \(difference)")
            
            if (difference > 0) {
                tempMin = testedSize
            } else {
                tempMax = testedSize
            }
        }
        
        // returning the size -1 (to have enought space right and left)
        return UIFont(name: fontName, size: tempMin)
    }
    
    class func simpleAdaptiveFontWithName(fontName: String, textView: UITextView, fontSize: CGFloat = 24) -> UIFont! {
        textView.font = UIFont(name: fontName, size: fontSize)
        var adaptiveFontSize = fontSize
        while (textView.contentSize.height < textView.frame.size.height) {
            adaptiveFontSize += 1
            textView.font = UIFont(name: fontName, size: adaptiveFontSize)
        }
        return textView.font
    }
    
    class func adaptiveFontWithName(fontName: String, textView: UITextView, fontSize: CGFloat = 24) -> UIFont!{
        textView.font = UIFont(name: fontName, size: fontSize)!
        let textViewSize = textView.frame.size;
        let fixedWidth = textViewSize.width;
        let adaptiveTextViewSize = textView.sizeThatFits(CGSizeMake(fixedWidth, CGFloat(MAXFLOAT)));
        var adaptiveFontSize = fontSize
        
        if (adaptiveTextViewSize.height > textViewSize.height) {
            while (textView.sizeThatFits(CGSizeMake(fixedWidth, CGFloat(MAXFLOAT))).height > textViewSize.height) {
                adaptiveFontSize -= 1
                textView.font = textView.font!.fontWithSize(adaptiveFontSize)
            }
        } else {
            while (textView.sizeThatFits(CGSizeMake(fixedWidth, CGFloat(MAXFLOAT))).height < textViewSize.height) {
                adaptiveFontSize += 1
                textView.font = textView.font!.fontWithSize(adaptiveFontSize)
            }
        }
        return textView.font
    }
}