title: Set the center of a UIButton programmatically - SWIFT
body: <p>I have a <code>UIButton</code> inside a <code>UIView</code>, my <code>UIButton</code> has constraints which I set in storyboard. Now, I want to set the center of the <code>UIButton</code> at the center of the <code>UIView</code>. How will I do that programmatically?</p>