Extensions May not contain Stored properties

Question

Can I implement this in Swift with Extensions without the need to inheritance?. I get this error Extensions May not contain Stored properties

extension UIB         


        

Answer 1

Extensions cannot add stored properties. From the docs (Computed Properties section):

Note

Extensions can add new computed properties, but they cannot add stored properties, or add property observers to existing properties.

If you have a need for stored properties, you should create a subclass, like so:

class CustomButton : UIButton
{
    @IBInspectable var borderWidth : CGFloat
        {
        didSet{
            layer.borderWidth = borderWidth
        }
    }

}