Swift - Attributed strings in buttons

Question

I have some UIbuttons in my app that have a number indicator before the text. Right now, I am just using string interpolation to display the number before the string as seen below.

fruitButton.setTitle("\(fruitCounter) Fruits", forState: UIControlState.Normal)

I need the number to stand out more, rather than just blending in with the title text. Something as simple as a circle surrounding it will do the trick, as seen in the design below: .

I did some research on Attributed Strings in Swift. However, I am just seeing many examples on changing text properties. EG - changing the text color and size of the number indicator. I can't figure out how to add a circle behind.

I do not want this circle to be an image, simply for scalibility purposes. For instance, if that number ends up being 2 digits long, I need the circle to stretch to oval. My thought was using a small view behind the number, and then just applying a color / alpha / radius to achieve the look I need.

So to wrap this up: How can I add circles behind my number indicators using Attributed Strings in Swift?

Answer 1

You should create a UIView subclass that will contain these two elements. Create a corresponding .xib file that includes those entities or implement those entities in code. You can also implement touchesBegan so that this view can act like a button OR add a button instead of a text label and implement a protocol to fire every time the button is hit. I've started this for you with some semi-arbitrary numbers. You'll have to play with them to get them just right.

class UICoolButton: UIView {

    var labelText: NSString?
    var circledNumber: Int?
    var circleSubview: UIView?

    init(frame: CGRect, labelText: NSString, circledNumber: Int) {
        super.init(frame: frame);
        self.labelText = labelText;
        self.circledNumber = circledNumber;
        self.layer.cornerRadius = frame.height/3
        self.clipsToBounds = true
        addCircledNumber()
        addTextLabel(labelText)
    }

    func setColors(numberColor:UIColor, backgroundColor: UIColor) {
        self.backgroundColor = backgroundColor
        self.circleSubview?.backgroundColor = numberColor
    }

    override init(frame: CGRect) {
        super.init(frame: frame);
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder);
    }

    func addTextLabel(text: NSString) {
        let origin = CGPoint(x:self.frame.width * 0.4, y:self.frame.height/10)
        let size = CGSize(width: self.frame.width/2, height: self.frame.height * 0.8)
        let rect = CGRect(origin: origin, size: size)
        let label = UILabel(frame: rect)
        let attributes: [String : AnyObject] = [NSFontAttributeName : UIFont(name: "Verdana", size: 16.0)!,
        NSForegroundColorAttributeName : UIColor.whiteColor()]

        label.attributedText = NSAttributedString(string: text, attributes: attributes)

        self.addSubview(label)
    }

    override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {

    }

    func addCircledNumber() {
        let height = self.frame.height * 0.4;
        let circleDimensions = CGSize(width: height , height:height)
        let origin = CGPointMake(self.frame.width * 0.15, self.frame.height - self.frame.height/1.5)
        let circleSubview = UIView(frame: CGRect(origin: origin, size: circleDimensions))
        circleSubview.layer.cornerRadius = height/2;
        circleSubview.backgroundColor = UIColor.darkGrayColor()

        let labelHeight = height * 0.8;

        let xPosition = circleSubview.bounds.origin.x + 3
        let yPosition = circleSubview.bounds.origin.y + 2

        let labelOrigin =  CGPoint(x: xPosition, y: yPosition)
        let labelRect = CGRect(origin: labelOrigin, size: CGSize(width: labelHeight, height: labelHeight))
        let numberLabel = UILabel(frame: labelRect);
        numberLabel.textAlignment = NSTextAlignment.Center

        let numberAsString = NSString(format: "%i", circledNumber!) as String
        let attributes: [String : AnyObject] = [NSFontAttributeName : UIFont(name: "Verdana", size: 16.0)!,
        NSForegroundColorAttributeName : UIColor.whiteColor()]
        numberLabel.attributedText = NSAttributedString(string: numberAsString, attributes: attributes)
        circleSubview.addSubview(numberLabel);
        self.circleSubview = circleSubview
        self.addSubview(circleSubview)
    }

Then in your View Controller, use the initilizer I wrote:

func addCoolButton() {
    let rect = CGRect() //choose the frame for your button here
    let button = UICoolButton(frame: rect, labelText: "Example", circledNumber: 10);

    let backgroundColor = UIColor(red: 243/255.0 , green: 93/255.0, blue: 118/255.0, alpha: 1.0)
    let numberColor = UIColor(red: 252/255.0, green: 118.0/255.0, blue: 135/255.0, alpha: 1.0)
    button.setColors(numberColor, backgroundColor: backgroundColor)

    self.view.addSubview(button)
}