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iOS UIColor Category 十六进制颜色值转换

iOS UIColor Category 十六进制颜色值转换

作者: Joker_Lee | 来源:发表于2018-06-30 19:19 被阅读359次
[UIColor colorWithRed:(r)/255.0 green:(g)/255.0 blue:(b)/255.0 alpha:1];

UIColor只提供了上面的方法用于创建一个RGBA的颜色值,但是开发中大部分用的是喜闻乐见的16进制的字符串或者整数,例如:

LightPink 浅粉红 #FFB6C1 255,182,193
Indigo 靛青 #4B0082 75,0,130

所以使用分类去增加一些方法让颜色的转换更加方便势在必行。
使用示例:

#import "UIColor+Utils.h"

- (void)testColors {
    UIColor *color = RGBHex(0x334422);
    ARGBHex(0xffccaabb);
//    UIColor *color = [UIColor colorWithHexRGB:(0xFFC0CB)];
    UIColor *colorTest = [UIColor colorWithHexARGB:0xFFCACBCE];
    NSLog(@"%@",color);
    NSLog(@" RGB:%@, ARGB:%@",[color toHexRGB], [color toHexARGB]);
    NSLog(@"A:%0x, R:%0x, G:%0x, B:%0x ", [color toRGBA].a, [color toRGBA].r, [color toRGBA].g,[color toRGBA].b);
}

具体实现代码如下:

//
//  UIColor+Utils.h
//
//  Created by Jokerlee on 2018/6/28.
//  Copyright © 2018年 Jokerlee. All rights reserved.
//
#import <UIKit/UIKit.h>

struct RGBA {
    UInt8 r;
    UInt8 g;
    UInt8 b;
    UInt8 a;
};

@interface UIColor (Utils)
//---------------------------------------------------------------------------
#pragma mark macros for generating colors
//---------------------------------------------------------------------------
#define RGBInt(r,g,b) [UIColor colorWithRed:(r)/255.0 green:(g)/255.0 blue:(b)/255.0 alpha:1]
#define RGBAInt(r,g,b,a) [UIColor colorWithRed:(r)/255.0 green:(g)/255.0 blue:(b)/255.0 alpha:(a)/255.0]

#define RGBHex(rgb) [UIColor colorWithHexRGB:rgb]
#define RGBAHex(rgba) [UIColor colorWithHexRGBA:rgba]
#define ARGBHex(argb) [UIColor colorWithHexARGB:argb]

//---------------------------------------------------------------------------
#pragma mark methods for generating colors
//---------------------------------------------------------------------------

+ (UIColor *)colorWithHexRGB:(NSUInteger)hexRGB;
+ (UIColor *)colorWithHexRGBA:(NSUInteger)hexRGBA;
+ (UIColor *)colorWithHexARGB:(NSUInteger)hexARGB;
+ (UIColor *)colorWithHexStringRGB:(NSString *)hexRGB;

//---------------------------------------------------------------------------
#pragma mark methods for color converting
//---------------------------------------------------------------------------

- (NSString *)toHexRGB;
- (NSString *)toHexRGBA;
- (NSString *)toHexARGB;

- (struct RGBA)toRGBA;

@end
//
//  UIColor+Utils.m
//
//  Created by Jokerlee on 2018/6/28.
//  Copyright © 2018年 Jokerlee. All rights reserved.
//

#import "UIColor+Utils.h"

@implementation UIColor (Utils)

+ (UIColor *)colorWithIntegerRed:(NSUInteger)red green:(NSUInteger)green blue:(NSUInteger)blue {
    return [UIColor colorWithRed:red/255.0f green:green/255.0f blue:blue/255.0f alpha:1.0f];
}

+ (UIColor *)colorWithIntegerRed:(NSUInteger)red green:(NSUInteger)green blue:(NSUInteger)blue alpha:(CGFloat)alpha {
    return [UIColor colorWithRed:red/255.0f green:green/255.0f blue:blue/255.0f alpha:alpha];
}

+ (UIColor *)colorWithHexRGB:(NSUInteger)hexRGB {
    return [UIColor colorWithIntegerRed:((hexRGB & 0xFF0000) >> 16) green:((hexRGB & 0x00FF00) >> 8) blue:(hexRGB & 0x0000FF) alpha:1.0f];
}

+ (UIColor *)colorWithHexRGBA:(NSUInteger)hexRGBA {
    return [UIColor colorWithIntegerRed:((hexRGBA & 0xFF000000) >> 24) green:((hexRGBA & 0x00FF0000) >> 16) blue:((hexRGBA & 0x0000FF00) >> 8) alpha:(hexRGBA & 0x000000FF)/255.0f];
}

+ (UIColor *)colorWithHexARGB:(NSUInteger)hexARGB {
    return [UIColor colorWithIntegerRed:((hexARGB & 0x00FF0000) >> 16) green:((hexARGB & 0x0000FF00) >> 8) blue:(hexARGB & 0x000000FF) alpha:((hexARGB & 0xFF000000) >> 24)/255.0f];
}

- (NSString *)toHexRGB {
    CGColorRef color = self.CGColor;
    size_t count = CGColorGetNumberOfComponents(color);
    const CGFloat *components = CGColorGetComponents(color);
    
    static NSString *stringFormat = @"%02x%02x%02x";
    
    if (count == 2) {
        // Grayscale
        NSUInteger grey = (NSUInteger)(components[0] * (CGFloat)255);
        return [NSString stringWithFormat:stringFormat, grey, grey, grey];
    }
    else if (count == 4) {
        // RGB
        return [NSString stringWithFormat:stringFormat,
                (NSUInteger)(components[0] * (CGFloat)255),
                (NSUInteger)(components[1] * (CGFloat)255),
                (NSUInteger)(components[2] * (CGFloat)255)];
    }
    
    // Unsupported color space
    return nil;
}

- (NSString *)toHexARGB {
    CGColorRef color = self.CGColor;
    size_t count = CGColorGetNumberOfComponents(color);
    const CGFloat *components = CGColorGetComponents(color);
    
    static NSString *stringFormat = @"%02x%02x%02x%02x";
    
    if (count == 2) {
        // Grayscale
        NSUInteger grey = (NSUInteger)(components[0] * (CGFloat)255);
        NSUInteger alpha = (NSUInteger)(components[3] * (CGFloat)255);
        return [NSString stringWithFormat:stringFormat, grey, grey, grey, alpha];
    }
    else if (count == 4) {
        // RGBA
        return [NSString stringWithFormat:stringFormat,
                (NSUInteger)(components[3] * (CGFloat)255),
                (NSUInteger)(components[0] * (CGFloat)255),
                (NSUInteger)(components[1] * (CGFloat)255),
                (NSUInteger)(components[2] * (CGFloat)255)];
    }
    
    // Unsupported color space
    return nil;
}

- (NSString *)toHexRGBA {
    CGColorRef color = self.CGColor;
    size_t count = CGColorGetNumberOfComponents(color);
    const CGFloat *components = CGColorGetComponents(color);
    
    static NSString *stringFormat = @"%02x%02x%02x%02x";
    
    if (count == 2) {
        // Grayscale
        NSUInteger grey = (NSUInteger)(components[0] * (CGFloat)255);
        NSUInteger alpha = (NSUInteger)(components[3] * (CGFloat)255);
        return [NSString stringWithFormat:stringFormat, grey, grey, grey, alpha];
    }
    else if (count == 4) {
        // RGBA
        return [NSString stringWithFormat:stringFormat,
                (NSUInteger)(components[0] * (CGFloat)255),
                (NSUInteger)(components[1] * (CGFloat)255),
                (NSUInteger)(components[2] * (CGFloat)255),
                (NSUInteger)(components[3] * (CGFloat)255)];
    }
    
    // Unsupported color space
    return nil;
}

- (struct RGBA)toRGBA {
    
    struct RGBA rgba = {0,0,0,0};
    
    CGColorRef color = self.CGColor;
    size_t count = CGColorGetNumberOfComponents(color);
    const CGFloat *components = CGColorGetComponents(color);
    
    if (count == 2) {
        // Grayscale
        NSUInteger grey = (NSUInteger)(components[0] * (CGFloat)255);
        NSUInteger alpha = (NSUInteger)(components[3] * (CGFloat)255);
        rgba.a = alpha;
        rgba.r = grey;
        rgba.g = grey;
        rgba.b = grey;
        return rgba;
    } else if (count == 4) {
        // RGBA
        rgba.a = (NSUInteger)(components[3] * (CGFloat)255);
        rgba.r = (NSUInteger)(components[0] * (CGFloat)255);
        rgba.g = (NSUInteger)(components[1] * (CGFloat)255);
        rgba.b = (NSUInteger)(components[2] * (CGFloat)255);
        return rgba;
    }
    // Unsupported color space
    return rgba;
}

+ (UIColor *)colorWithHexStringRGB:(NSString *)hexColor {
    
    if(!hexColor || [hexColor isKindOfClass:[NSNull class]]){
        return [UIColor blackColor];
    }
    
    hexColor = [[hexColor stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];

    // String should be 6 or 7 characters if it includes '#'
    if ([hexColor length] < 6)
        return [UIColor blackColor];
    
    // strip # if it appears
    if ([hexColor hasPrefix:@"#"])
        hexColor = [hexColor substringFromIndex:1];
    
    // if the value isn't 6 characters at this point return
    // the color black
    if ([hexColor length] != 6)
        return [UIColor blackColor];
    
    // Separate into r, g, b substrings
    NSRange range;
    range.location = 0;
    range.length = 2;
    
    NSString *rString = [hexColor substringWithRange:range];
    
    range.location = 2;
    NSString *gString = [hexColor substringWithRange:range];
    
    range.location = 4;
    NSString *bString = [hexColor 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

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