Define custom colors Swift

Question

I'm rewriting my app in Swift (yes, hooray) and I'm running into the following:

I inherited a class, of which the definition is (.h)

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>

@interface MWColor : NSObject

+ (UIColor *)gray;
+ (UIColor *)green;
+ (UIColor *)themeColor;


@end

In here, I define colors, that I can use throughout my project as such:

myView.backgroundColor = MWColor.gray()

Now, I want to do this in a proper Swift way.

What would be the best approach? Extensions?

Help me to be a good Swift citizen

Answer 1

You can add computed colours to UIColor in an extension like this...

extension UIColor {
    static var myRed: UIColor { 
        // define your color here
        return UIColor(...) 
    }
}

or even...

extension UIColor {
    static let myRed = UIColor(... define the color values here ...)
}

Then access it like...

let someColor: UIColor = .myRed

or

let otherColor = UIColor.myRed

This matches the way that standard colours are defined too..

UIColor.red
UIColor.yellow
UIColor.myRed

etc...