将十六进制颜色代码转换为NSColor

Question

将十六进制颜色代码转换为NSColor

15

我在将十六进制代码转换为NSColor时遇到了一些问题。请注意，这是用于Mac应用程序的（因此使用NSColor而不是UIColor）。这是我目前拥有的代码：

- (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;

}

希望能得到任何帮助。

- mdominick

你能提供一个string值的示例吗？ - Andrew Madsen

从输入中，你得到了哪些红色、绿色和蓝色的值？ - Peter Hosey

以上数值的输出为0.2 0.6 0.4 1，其中最后一个是alpha。 - mdominick

6个回答

8

以下是两个非常有用的宏：

#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]

- serj

宏是实用的，但通常因为很多原因而不好。 - uchuugaka

4

这是Zlatan上面回答的适用于Swift 2的版本（+1给他！）：

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
}

- Michael Dautermann

0

PocketSVG中的hexTriplet结构包含了一个有趣的替代方案。它输出一个CGColor，但如果你想要跨平台使用它，这可能是一件好事：

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

- Svetlyo

0

支持7种十六进制类型：

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/

注意：这不是即插即用的，您需要在代码中深入挖掘一下。但所有内容都在那里，而且可能比自己编写更快。

- Sentry.co

0

+(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];
}

您可能需要：

#include <stdlib.h>

- DTs

网页内容由stack overflow 提供, 点击上面的

可以查看英文原文，
原文链接

- Zlatan · Accepted Answer

+ (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;
    }

它没有考虑alpha值，而是假设像"FFAABB"这样的值，但很容易进行修改。