UIKit extensions with additional @IBInspectable properties

UIButton+BackgroundColor.swift

import UIKit

extension UIButton {
    
    @IBInspectable var disabledBackgroundColor: UIColor? {
        get {
            guard let image = image(for: .disabled) else { return nil }
            return UIColor(patternImage: image)
        }
        set { setBackgroundColor(newValue, for: .disabled) }
    }
    
    @IBInspectable var highlightedBackgroundColor: UIColor? {
        get {
            guard let image = image(for: .highlighted) else { return nil }
            return UIColor(patternImage: image)
        }
        set { setBackgroundColor(newValue, for: .highlighted) }
    }

    @IBInspectable var selectedBackgroundColor: UIColor? {
        get {
            guard let image = image(for: .selected) else { return nil }
            return UIColor(patternImage: image)
        }
        set { setBackgroundColor(newValue, for: .selected) }
    }

    func setBackgroundColor(_ color: UIColor?, for state: UIControl.State) {
        guard let color = color else {
            setBackgroundImage(nil, for: state)
            return
        }
        
        let size = CGSize(width: 1.0, height: 1.0)
        let image = UIGraphicsImageRenderer(size: size).image { context in
            context.cgContext.setFillColor(color.cgColor)
            context.fill(CGRect(origin: .zero, size: size))
        }
        setBackgroundImage(image, for: state)
    }
    
}

UIView+CornerRadius.swift

import UIKit

extension UIView {
    
    @IBInspectable var cornerRadius: CGFloat {
        get { layer.cornerRadius }
        set { layer.cornerRadius = newValue }
    }
    
}