颜色转换：＃hhhfff－>UIColor （MHHexColoring）
MHHexColoring为开发者快速获取想要的十六进制颜色（Hex Color）
查找16进制色码的网站：http://www.color-hex.com
// 版权属于原作者 MHHexColoring
http://code4app.com/ios/MHHexColoring/548e9485933bf0a9738b6301
加入UIColor+HexString.h/m文件，导入头文件：
#import "UIColor+HexString.h"
获取颜色，返回UIColor:
[UIColor colorWithHexString:@"#ffffff"];
2、 UIColor+HexString.h
// UIColor+HexString.h
// shopbox
//
// Created by Mohamed Hegab on 10/2/14.
// Copyright (c) 2014 The Dark Dimension. All rights reserved.
//
#import <UIKit/UIKit.h>
@interface UIColor (HexString)
+ (UIColor *) colorWithHexString: (NSString *) hexString;
@end
3、 UIColor+HexString.m
#import "UIColor+HexString.h"
@implementation UIColor (HexString)
+ (CGFloat) colorComponentFrom: (NSString *) string start: (NSUInteger) start length: (NSUInteger) length {
NSString *substring = [string substringWithRange: NSMakeRange(start, length)];
NSString *fullHex = length == 2 ? substring : [NSString stringWithFormat: @"%@%@", substring, substring];
unsigned hexComponent;
[[NSScanner scannerWithString: fullHex] scanHexInt: &hexComponent];
return hexComponent / 255.0;
}
+ (UIColor *) colorWithHexString: (NSString *) hexString {
NSString *colorString = [[hexString stringByReplacingOccurrencesOfString: @"#" withString: @""] uppercaseString];
CGFloat alpha, red, blue, green;
switch ([colorString length]) {
case 3: // #RGB
alpha = 1.0f;
red = [self colorComponentFrom: colorString start: 0 length: 1];
green = [self colorComponentFrom: colorString start: 1 length: 1];
blue = [self colorComponentFrom: colorString start: 2 length: 1];
break;
case 4: // #ARGB
alpha = [self colorComponentFrom: colorString start: 0 length: 1];
red = [self colorComponentFrom: colorString start: 1 length: 1];
green = [self colorComponentFrom: colorString start: 2 length: 1];
blue = [self colorComponentFrom: colorString start: 3 length: 1];
break;
case 6: // #RRGGBB
alpha = 1.0f;
red = [self colorComponentFrom: colorString start: 0 length: 2];
green = [self colorComponentFrom: colorString start: 2 length: 2];
blue = [self colorComponentFrom: colorString start: 4 length: 2];
break;
case 8: // #AARRGGBB
alpha = [self colorComponentFrom: colorString start: 0 length: 2];
red = [self colorComponentFrom: colorString start: 2 length: 2];
green = [self colorComponentFrom: colorString start: 4 length: 2];
blue = [self colorComponentFrom: colorString start: 6 length: 2];
break;
default:
return nil;
}
return [UIColor colorWithRed: red green: green blue: blue alpha: alpha];
}
@end
