title: UIButton with circle frame and number in it
body: <p>I want to make a button with a circle frame like the default iOS one in lock screen where you enter your passcode to unlock the iPhone. I have tried it with custom UIButton class but no matter what I did title (the numbers 0,1,2...) wasn't showing in the buttons (circle buttons empty inside). I do not want to repeat the same code for each 10 buttons. I am working with swift.</p>