UIColor to Hexadecimal (web color)

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

Answer 1

Other than the widely used string based solution, here's a hex (integer) based solution. Usage:

UIColor* color = lf_rgb(0x120aef);
log(@"color %.6x", color.hex_rgb);

And you'll get "color 120aef". I'll put these code in https://github.com/superarts/LCategory, or you can copy-paste into your own code bank too:

#define lf_rgb(rgbValue)    [UIColor colorWithRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 green:((float)((rgbValue & 0xFF00) >> 8))/255.0 blue:((float)(rgbValue & 0xFF))/255.0 alpha:1.0]

@interface UIColor (lc_rgb)
- (NSInteger)hex_rgb;
@end

@implementation UIColor (lc_rgb)
- (NSInteger)hex_rgb
{
    CGFloat r, g, b, a;
    BOOL result = [self getRed:&r green:&g blue:&b alpha:&a];
    //  log(@"rgba: %f, %f, %f, %f", r * 255, g * 255, b * 255, a * 255);
    if ((result == NO) || (a != 1.0f))
        return -1;
    return 
        (NSInteger)(r * 255) * 256 * 256 + 
        (NSInteger)(g * 255) * 256 +
        (NSInteger)(b * 255) * 1;
}
@end