Create a rectangle with just two rounded corners in swift?

Question

I need to create a rectangle that have just two rounded corners in swift (Objective C code also ok).

At the moment my code is creating two rectangles with

Answer 1

Building on top of Sanjay's excellent answer, I wrote a quick CALayer extension for Swift 2.3, in case you need to do this sort of "only round some corners" thing more than once.

extension CALayer {
  func roundCorners(corners: UIRectCorner, radius: CGFloat) {
    let maskPath = UIBezierPath(roundedRect: bounds,
                                byRoundingCorners: corners,
                                cornerRadii: CGSize(width: radius, height: radius))

    let shape = CAShapeLayer()
    shape.path = maskPath.CGPath
    mask = shape
  }
}

Usage:

myView.layer.roundCorners([.TopLeft, .TopRight], radius: myCornerRadius)

Swift 3.0 (In this example the bounds came from the view not from the layer. Using the bounds from the view make this code to work with views in a UITableViewCell.):

func roundCorners(corners: UIRectCorner, radius: CGFloat, viewBounds: CGRect) {

    let maskPath = UIBezierPath(roundedRect: viewBounds,
                                byRoundingCorners: corners,
                                cornerRadii: CGSize(width: radius, height: radius))

    let shape = CAShapeLayer()
    shape.path = maskPath.cgPath
    mask = shape
}

Usage:

myView.layer.roundCorners(corners: [.topLeft, .topRight], radius: myCornerRadius, viewBounds: bounds)