title: How to set layer cornerRadius for only bottom-left, bottom-right, and top-left corner?
body: <p>How to set corner radius only only bottom-left, bottom-right, and top-left corners of a textview?</p>
  <pre><code>let rectShape = CAShapeLayer()
  rectShape.backgroundColor = UIColor.redColor().CGColor
  rectShape.bounds = messages.frame
  rectShape.position = messages.center
  rectShape.path = UIBezierPath(roundedRect: messages.bounds, byRoundingCorners: .BottomLeft | .TopRight, cornerRadii: CGSize(width: 20, height: 20)).CGPath
  
  messages.layer.addSublayer(rectShape)
  </code></pre>
  <p>this code creates two rects. I dont know why.</p>