CODEWITHSUNDEEP
iphoneuicolor
openfrog
openfrog

Reputation: 40735

How to convert HEX RGB color codes to UIColor?

I have an RGB hex code like #ffffff as NSString and want to convert that into an UIColor. Is there a simple way to do that?

Upvotes: 65

Views: 63156

Answers (16)

Jonathon Hibbard
Jonathon Hibbard

Reputation: 1546

Guess this is a bit late here... but I found this version in the WhiteHouse Github repo that does it in a pretty elegant way:

+(UIColor *)colorFromRGBHexString:(NSString *)colorString {
    if(colorString.length == 7) {
        const char *colorUTF8String = [colorString UTF8String];
        int r, g, b;
        sscanf(colorUTF8String, "#%2x%2x%2x", &r, &g, &b);
        return [UIColor colorWithRed:(r / 255.0) green:(g / 255.0) blue:(b / 255.0) alpha:1.0];
    }    
    return nil;
}

Source Link to their WHAppConfig.m on github

Upvotes: 1

Eugene
Eugene

Reputation: 4456

I created an online tool to instantly convert any hex code to a UIColor code snippet for Swift and Objective-C, for when it's inconvenient to use custom methods or plugins: https://iosref.com/uihex/

Upvotes: 3

Tom Prats
Tom Prats

Reputation: 7911

If converting from ObjectiveC to swift is hard for you, here's the answer with Swift. Currently it only takes strings without the #, but you can add a scanner method to skip it I believe.

func stringToColor(stringColor: String) -> UIColor {
    var hexInt: UInt32 = 0
    let scanner = NSScanner(string: stringColor)
    scanner.scanHexInt(&hexInt)
    let color = UIColor(
        red: CGFloat((hexInt & 0xFF0000) >> 16)/255,
        green: CGFloat((hexInt & 0xFF00) >> 8)/255,
        blue: CGFloat((hexInt & 0xFF))/255,
        alpha: 1)

    return color
}

Upvotes: 3

Kemo
Kemo

Reputation: 488

+(UIColor*)colorWithHexString:(NSString*)hexString

{

NSString *cString = [[hexString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];

if ([cString length] < 6) return [UIColor grayColor];

if ([cString hasPrefix:@"0X"]) cString = [cString substringFromIndex:2];

if ([cString length] != 6) return  [UIColor grayColor];

NSRange range;
range.location = 0;
range.length = 2;
NSString *rString = [cString substringWithRange:range];

range.location = 2;
NSString *gString = [cString substringWithRange:range];

range.location = 4;
NSString *bString = [cString substringWithRange:range];

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];

}

Upvotes: 0

Ramesh
Ramesh

Reputation: 1763

I found a cocoapod library very useful in creating UIColor using "#RRGGBB" values.

pod 'UIColor-HexRGB'

Upvotes: 0

Blaine L
Blaine L

Reputation: 1

I think there is an even easier way when using HEX values. Just add a definition at the top of your file or reference a header file for the conversion (UIColorFromRGB). You can even add a template of fixed HEX color values. 

#define CLR_YELLOW_TEXT     0xf4dc89    // A Light Yellow text
#define CLR_GREEN_TEXT      0x008040    // Dark Green text for my buttons

#define UIColorFromRGB(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]

Then just reference it in your code using the HEX values directly or your defined hex values. For example...

[myButton1 setTitleColor:UIColorFromRGB(0xd02d2d) forState:UIControlStateNormal];
[myButton2 setTitleColor:UIColorFromRGB(CLR_GREEN_TEXT) forState:UIControlStateNormal];
[myButton3 setTitleColor:UIColorFromRGB(CLR_YELLOW_TEXT) forState:UIControlStateNormal];

(PS - This assumes an Alpha of 1.0, but it can always be changed in the definition).

Enjoy.

Upvotes: 0

Jim Rhoades
Jim Rhoades

Reputation: 3320

There is a nice category for UIColor called "UIColor+Expanded" which has a class method for getting a UIColor from an RGB hex string:

It's simple to use:

UIColor *myColor = [UIColor colorWithHexString:@"FF0000"];

Plus it adds a lot of other potentially useful utilities to UIColor. More info is available in this article.

Upvotes: 19

ChikabuZ
ChikabuZ

Reputation: 10185

+ (UIColor *)colorWithHexString:(NSString *)colorString
{
    colorString = [colorString stringByReplacingOccurrencesOfString:@"#" withString:@""];

    if (colorString.length == 3)
        colorString = [NSString stringWithFormat:@"%c%c%c%c%c%c",
        [colorString characterAtIndex:0], [colorString characterAtIndex:0],
        [colorString characterAtIndex:1], [colorString characterAtIndex:1],
        [colorString characterAtIndex:2], [colorString characterAtIndex:2]];

    if (colorString.length == 6)
    {
        int r, g, b;
        sscanf([colorString UTF8String], "%2x%2x%2x", &r, &g, &b);
        return [UIColor colorWithRed:(r/255.0) green:(g/255.0) blue:(b/255.0) alpha:1.0];
    }
    return nil;
}

for format #123, 123, #fff195, fff195

+ (UIColor *)colorWithHexValue:(int)hexValue
{
    float red   = ((hexValue & 0xFF0000) >> 16)/255.0;
    float green = ((hexValue & 0xFF00) >> 8)/255.0;
    float blue  = (hexValue & 0xFF)/255.0;
    return [UIColor colorWithRed:red green:green blue:blue alpha:1.0];
}

for format 0xfff195

Upvotes: 7

Ehsan
Ehsan

Reputation: 1022

The easiest way that I found: Hex to UIColor Converter

Just type the hex number without '#', and it returns the UIColor code. For example the code for the orange color (#f77f00) is:

[UIColor colorWithRed:0.969 green:0.498 blue:0 alpha:1.0]

Upvotes: 5

Bhatia
Bhatia

Reputation: 351

I was looking for a simple solution and came up with this (not completely Objective-C, but works like a charm):

NSString *stringColor = @"#AABBCC";
NSUInteger red, green, blue;
sscanf([stringColor UTF8String], "#%02X%02X%02X", &red, &green, &blue);

UIColor *color = [UIColor colorWithRed:red/255.0 green:green/255.0 blue:blue/255.0 alpha:1];

Upvotes: 35

Kyle Clegg
Kyle Clegg

Reputation: 39460

Don't forget that you have the option to convert your hex values to RGB and enter them in the interface builder. It'll save some lines of code.

rgb sliders

Upvotes: 1

MikeTheCoder
MikeTheCoder

Reputation: 963

Easy, Just go to this website and type in your hex value: http://www.corecoding.com/utilities/rgb-or-hex-to-float.php

Upvotes: 10

Dave DeLong
Dave DeLong

Reputation: 243146

In some code of mine, I use 2 different functions:

void SKScanHexColor(NSString * hexString, float * red, float * green, float * blue, float * alpha) {
  NSString *cleanString = [hexString stringByReplacingOccurrencesOfString:@"#" withString:@""];
  if([cleanString length] == 3) {
      cleanString = [NSString stringWithFormat:@"%@%@%@%@%@%@", 
                     [cleanString substringWithRange:NSMakeRange(0, 1)],[cleanString substringWithRange:NSMakeRange(0, 1)],
                     [cleanString substringWithRange:NSMakeRange(1, 1)],[cleanString substringWithRange:NSMakeRange(1, 1)],
                     [cleanString substringWithRange:NSMakeRange(2, 1)],[cleanString substringWithRange:NSMakeRange(2, 1)]];
  }
  if([cleanString length] == 6) {
      cleanString = [cleanString stringByAppendingString:@"ff"];
  }

  unsigned int baseValue;
  [[NSScanner scannerWithString:cleanString] scanHexInt:&baseValue];

  if (red) { *red = ((baseValue >> 24) & 0xFF)/255.0f; }
  if (green) { *green = ((baseValue >> 16) & 0xFF)/255.0f; }
  if (blue) { *blue = ((baseValue >> 8) & 0xFF)/255.0f; }
  if (alpha) { *alpha = ((baseValue >> 0) & 0xFF)/255.0f; }
}

And then I use it like this:

UIColor * SKColorFromHexString(NSString * hexString) {
  float red, green, blue, alpha;
  SKScanHexColor(hexString, &red, &green, &blue, &alpha);

  return [UIColor colorWithRed:red green:green blue:blue alpha:alpha];
}

If you prefer to use this as a UIColor category, then it's just a matter of altering a few lines:

+ (UIColor *) colorFromHexString:(NSString *)hexString {
  NSString *cleanString = [hexString stringByReplacingOccurrencesOfString:@"#" withString:@""];
  if([cleanString length] == 3) {
      cleanString = [NSString stringWithFormat:@"%@%@%@%@%@%@", 
                     [cleanString substringWithRange:NSMakeRange(0, 1)],[cleanString substringWithRange:NSMakeRange(0, 1)],
                     [cleanString substringWithRange:NSMakeRange(1, 1)],[cleanString substringWithRange:NSMakeRange(1, 1)],
                     [cleanString substringWithRange:NSMakeRange(2, 1)],[cleanString substringWithRange:NSMakeRange(2, 1)]];
  }
  if([cleanString length] == 6) {
      cleanString = [cleanString stringByAppendingString:@"ff"];
  }

  unsigned int baseValue;
  [[NSScanner scannerWithString:cleanString] scanHexInt:&baseValue];

  float red = ((baseValue >> 24) & 0xFF)/255.0f;
  float green = ((baseValue >> 16) & 0xFF)/255.0f;
  float blue = ((baseValue >> 8) & 0xFF)/255.0f;
  float alpha = ((baseValue >> 0) & 0xFF)/255.0f;

  return [UIColor colorWithRed:red green:green blue:blue alpha:alpha];
}

This will handle strings like "#abc", "#abcdef31", etc.

Upvotes: 101

matteodv
matteodv

Reputation: 3982

If you don't want to write all of this code above, you can check this site: http://www.diovo.com/apps/rgb-to-uicolor-converter.html
From an HEX color like this: #FFFFFF, the site convert it in a string like this:

UIColor *aColor = [UIColor colorWithRed:1 green:1 blue:1 alpha:1.000];

Upvotes: 2

k-thorat
k-thorat

Reputation: 5123

If you are using Hex Values.. 

#define UIColorFromRGB(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]

  //Then use any Hex value

 self.view.backgroundColor = UIColorFromRGB(0xD2691E);

Upvotes: 84

Codebeef
Codebeef

Reputation: 43996

I think I'd split the six characters into three pairs, then convert that to decimal, then divide that by 255 to get each color component as a float.

You can then pass the components to:

[UIColor colorWithRed: green: blue: alpha:1];

Upvotes: 3

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