CODEWITHSUNDEEP
objective-cmacoscocoa
mdominick
mdominick

Reputation: 1319

Convert Hex Color Code to NSColor

I am having some trouble converting a a hexcode to an NSColor. Note this is for a Mac App (hence the NSColor instead of UIColor). This is the code I have so far:

- (NSColor *) createNSColorFromString:(NSString *)string {
NSString* hexNum = [string substringFromIndex:1];
NSColor* color = nil;
unsigned int colorCode = 0;
unsigned char red, green, blue;
if (string) {
    NSScanner* scanner = [NSScanner scannerWithString:hexNum];
    (void) [scanner scanHexInt:&colorCode];
}
red = (unsigned char) (colorCode >> 16);
green = (unsigned char) (colorCode >> 8);
blue = (unsigned char) (colorCode);
color = [NSColor colorWithCalibratedRed:(float)red / 0xff green:(float)green / 0xff blue:(float)blue / 0xff alpha:1.0];
return color;

}

Any help would be appreciated.

Upvotes: 15

Views: 13409

Answers (6)

DTs
DTs

Reputation: 1316

+(NSColor *) colorWithHexString:(NSString *)hexString alpha:(CGFloat)alpha {
    unsigned long int hexValue = strtoul(hexString.UTF8String, NULL, 16);
    return [NSColor colorWithHex:hexValue alpha:alpha];
}

+(NSColor *) colorWithHex:(unsigned long int)hexValue alpha:(CGFloat)alpha {
    return [NSColor colorWithRed:((float)((hexValue & 0xFF0000) >> 16))/255.0
                           green:((float)((hexValue & 0x00FF00) >>  8))/255.0
                            blue:((float)((hexValue & 0x0000FF) >>  0))/255.0
                           alpha:alpha];
}

You may need:

#include <stdlib.h>

Upvotes: 0

Svetlyo
Svetlyo

Reputation: 1

The hexTriplet struct in PocketSVG contains an interesting alternative solution. It outputs a CGColor but that's probably a good thing if you want to use it cross-platform:

https://github.com/pocketsvg/PocketSVG/blob/master/Sources/SVGEngine.mm

Upvotes: 0

Michael Dautermann
Michael Dautermann

Reputation: 89509

Here's the swift 2 compatible version of Zlatan's answer above (and +1 to him!):

func getColorFromString(webColorString : String) -> NSColor?
{
    var result : NSColor? = nil
    var colorCode : UInt32 = 0
    var redByte, greenByte, blueByte : UInt8

    // these two lines are for web color strings that start with a #
    // -- as in #ABCDEF; remove if you don't have # in the string
    let index1 = webColorString.endIndex.advancedBy(-6)
    let substring1 = webColorString.substringFromIndex(index1)

    let scanner = NSScanner(string: substring1)
    let success = scanner.scanHexInt(&colorCode)

    if success == true {
        redByte = UInt8.init(truncatingBitPattern: (colorCode >> 16))
        greenByte = UInt8.init(truncatingBitPattern: (colorCode >> 8))
        blueByte = UInt8.init(truncatingBitPattern: colorCode) // masks off high bits

        result = NSColor(calibratedRed: CGFloat(redByte) / 0xff, green: CGFloat(greenByte) / 0xff, blue: CGFloat(blueByte) / 0xff, alpha: 1.0)
    }
    return result
}

Upvotes: 4

Sentry.co
Sentry.co

Reputation: 5569

Support for 7 hex types:

NSColorParser.nsColor("#FF0000",1)//red nsColor
NSColorParser.nsColor("FF0",1)//red nsColor
NSColorParser.nsColor("0xFF0000",1)//red nsColor
NSColorParser.nsColor("#FF0000",1)//red nsColor
NSColorParser.nsColor("FF0000",1)//red nsColor
NSColorParser.nsColor(0xFF0000,1)//red nsColor
NSColorParser.nsColor(16711935,1)//red nsColor

http://stylekit.org/blog/2015/11/09/Supporting-7-Hex-color-types/

NOTE: This isn't plug and play, you have to dig a little in the code. But its all there and its probably faster than rolling your own.

Upvotes: 0

serj
serj

Reputation: 301

Here is two very useful macros

#define RGBA(r,g,b,a) [NSColor colorWithCalibratedRed:r/255.f green:g/255.f blue:b/255.f alpha:a/255.f]

#define NSColorFromRGB(rgbValue) [NSColor colorWithCalibratedRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 green:((float)((rgbValue & 0xFF00) >> 8))/255.0 blue:((float)(rgbValue & 0xFF))/255.0 alpha:1.0]

Upvotes: 8

Zlatan
Zlatan

Reputation: 698

+ (NSColor*)colorWithHexColorString:(NSString*)inColorString
{
    NSColor* result = nil;
    unsigned colorCode = 0;
    unsigned char redByte, greenByte, blueByte;

    if (nil != inColorString)
    {
         NSScanner* scanner = [NSScanner scannerWithString:inColorString];
         (void) [scanner scanHexInt:&colorCode]; // ignore error
    }
    redByte = (unsigned char)(colorCode >> 16);
    greenByte = (unsigned char)(colorCode >> 8);
    blueByte = (unsigned char)(colorCode); // masks off high bits

    result = [NSColor
    colorWithCalibratedRed:(CGFloat)redByte / 0xff
    green:(CGFloat)greenByte / 0xff
    blue:(CGFloat)blueByte / 0xff
    alpha:1.0];
    return result;
    }

It doesn't take alpha values into account, it assumes values like "FFAABB", but it would be easy to modify.

Upvotes: 28

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