Question

Is there an easy way to convert UIColor to a hexadecimal value ?
Or do we have to get the RGB components with CGColorGetComponents and then work it out from there?

e.g CGColorGetComponents(color.CGColor)[0] * 256 ?

Answer 1

I would consider using Erica Sadun’s UIColor category. It includes a lot of functionality for free, including hex representations. It’s pretty easy to use, just add it to whatever class header you’re using it in or, add it to the pre-compiled header for ultimate flexibility.
If you’re adding to the pre-compiled header, do so similar to something like this:

#ifdef __OBJC__
    #import <Foundation/Foundation.h>
    #import <UIKit/UIKit.h>
    #import "UIColor-Expanded.h"
#endif

Then You can use it like so NSLog(@"%@", [myColor hexStringFromColor]);

GitHub link to the UIColor category: https://github.com/erica/uicolor-utilities

ArsTechnica article about it: http://arstechnica.com/apple/guides/2009/02/iphone-development-accessing-uicolor-components.ars