UIBezierPath roundedRect - change color of corners

Question

I have a simple rounded rect

override func draw(_ rect: CGRect) {
    let path = UIBezierPath(roundedRect: rect, byRoundingCorners: UIRectCorner.allCorners, cornerRadii: CGSize(width: cornerSize, height: cornerSize))
    fillColor.setFill()
    path.fill()
    //fillColor is set to UIColor.black
    //cornerSize is set to 20
}

But the corners are white. If I set background color in UIBuilder to clear color, the rounded rect becomes a rect with sharp corners. I tried to create an oval with rect and fill it with clear color. This also didn't work. Maybe the answer is trivial but I'm absolutely clueless.

Answer 1

Your code works fine as it is. If it is drawing solid black when the views background color is clear then that probably means you have a black view of the same size behind your bezier view. You can test this by changing the fill color of your bezier curve to something other than black.

Its a lot easier to debug if you use the @IBDesignable and @IBInspectable keywords:

@IBDesignable class BezierView: UIView {

@IBInspectable var fillColor = UIColor.black

@IBInspectable var cornerRadius = 20.0

override func draw(_ rect: CGRect) {
    let path = UIBezierPath(roundedRect: rect, byRoundingCorners: UIRectCorner.allCorners, cornerRadii: CGSize(width: cornerRadius, height: cornerRadius))
    fillColor.setFill()
    path.fill()
}

}

It will then draw the view in the storyboard and you can edit the fill color and corner radius in the views inspector.