UIColor+Category.h

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

@interface UIColor (_16ToRGB)
+ (UIColor *)colorWithHexString:(NSString *)color;
@end

@interface BasicFactoryColor : NSObject
@end

UIColor+Category.m

#import "BasicFactoryColor.h"

@implementation BasicFactoryColor

+ (UIColor *)colorWithHexString:(NSString *)color
{
    NSString *cString = [[color stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];
    
    // String should be 6 or 8 characters
    if ([cString length] < 6) {
        return [UIColor clearColor];
    }
    
    // strip 0X if it appears
    if ([cString hasPrefix:@"0X"])
        cString = [cString substringFromIndex:2];
    if ([cString hasPrefix:@"#"])
        cString = [cString substringFromIndex:1];
    
    NSRange range;
    range.length = 2;
    
    if ([cString length] == 6) {
        // Separate into r, g, b substrings
        //r
        range.location = 0;
        NSString *rString = [cString substringWithRange:range];
        
        //g
        range.location = 2;
        NSString *gString = [cString substringWithRange:range];
        
        //b
        range.location = 4;
        NSString *bString = [cString substringWithRange:range];
        
        // Scan values
        unsigned int r, g, b;
        [[NSScanner scannerWithString:rString] scanHexInt:&r];
        [[NSScanner scannerWithString:gString] scanHexInt:&g];
        [[NSScanner scannerWithString:bString] scanHexInt:&b];
        
        return [UIColor colorWithRed:((float) r / 255.0f) green:((float) g / 255.0f) blue:((float) b / 255.0f) alpha:1.0f];
    } else if([cString length] == 8) {
        // Separate into r, g, b substrings
        
        //a
        range.location = 0;
        NSString *aString = [cString substringWithRange:range];
        //r
        range.location = 2;
        NSString *rString = [cString substringWithRange:range];
        
        //g
        range.location = 4;
        NSString *gString = [cString substringWithRange:range];
        
        //b
        range.location = 6;
        NSString *bString = [cString substringWithRange:range];
        
        // Scan values
        unsigned int a, r, g, b;
        [[NSScanner scannerWithString:aString] scanHexInt:&a];
        [[NSScanner scannerWithString:rString] scanHexInt:&r];
        [[NSScanner scannerWithString:gString] scanHexInt:&g];
        [[NSScanner scannerWithString:bString] scanHexInt:&b];
        
        return [UIColor colorWithRed:((float) r / 255.0f) green:((float) g / 255.0f) blue:((float) b / 255.0f) alpha:((float) a / 255.0f)];
        
    } else {
        return [UIColor clearColor];
    }
}

@end

@implementation UIColor (_16ToRGB)
+ (UIColor *)colorWithHexString:(NSString *)color
{
    NSString *cString = [[color stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];
    
    // String should be 6 or 8 characters
    if ([cString length] < 6) {
        return [UIColor clearColor];
    }
    
    // strip 0X if it appears
    if ([cString hasPrefix:@"0X"])
        cString = [cString substringFromIndex:2];
    if ([cString hasPrefix:@"#"])
        cString = [cString substringFromIndex:1];
    if ([cString length] != 6)
        return [UIColor clearColor];
    
    // Separate into r, g, b substrings
    NSRange range;
    range.location = 0;
    range.length = 2;
    
    //r
    NSString *rString = [cString substringWithRange:range];
    
    //g
    range.location = 2;
    NSString *gString = [cString substringWithRange:range];
    
    //b
    range.location = 4;
    NSString *bString = [cString substringWithRange:range];
    
    // Scan values
    unsigned int r, g, b;
    [[NSScanner scannerWithString:rString] scanHexInt:&r];
    [[NSScanner scannerWithString:gString] scanHexInt:&g];
    [[NSScanner scannerWithString:bString] scanHexInt:&b];
    
    return [UIColor colorWithRed:((float) r / 255.0f) green:((float) g / 255.0f) blue:((float) b / 255.0f) alpha:1.0f];
}


@end