相當(dāng)于一種選擇润梯，如果產(chǎn)品的需求圖里給出類似#ffffff這樣子網(wǎng)頁設(shè)計的顏色需求時，而我們也沒有用xib,或者storyboard來手動設(shè)置，而用純代碼的時候的處理氛悬，這里給出一個分類UIColor+Hex
UIColor+Hex.h
// 默認alpha位1
+ (UIColor *)colorWithHexString:(NSString *)color;
//從十六進制字符串獲取顏色购笆，
//color:支持@“#123456”粗悯、 @“0X123456”、 @“123456”三種格式
+ (UIColor *)colorWithHexString:(NSString *)color alpha:(CGFloat)alpha;
UIColor+Hex.m
+ (UIColor *)colorWithHexString:(NSString *)color alpha:(CGFloat)alpha
{
//刪除字符串中的空格
NSString *cString = [[color stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];
// String should be 6 or 8 characters
if ([cString length] < 6)
{
return [UIColor clearColor];
}
// strip 0X if it appears
//如果是0x開頭的同欠，那么截取字符串样傍，字符串從索引為2的位置開始，一直到末尾
if ([cString hasPrefix:@"0X"])
{
cString = [cString substringFromIndex:2];
}
//如果是#開頭的铺遂，那么截取字符串衫哥，字符串從索引為1的位置開始，一直到末尾
if ([cString hasPrefix:@"#"])
{
cString = [cString substringFromIndex:1];
}
if ([cString length] != 6)
{
return [UIColor clearColor];
}
// Separate into r, g, b substrings
NSRange range;
range.location = 0;
range.length = 2;
//r
NSString *rString = [cString substringWithRange:range];
//g
range.location = 2;
NSString *gString = [cString substringWithRange:range];
//b
range.location = 4;
NSString *bString = [cString 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:alpha];
}
//默認alpha值為1
+ (UIColor *)colorWithHexString:(NSString *)color
{
return [self colorWithHexString:color alpha:1.0f];
}
