将16进制的字符串转换为颜色

.m的文件

+ (UIColor *)colorWithHexString:(NSString *)color {
    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
    
    if ([cString hasPrefix:@"0X"])
        
        cString = [cString substringFromIndex:2];
    
    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:1.0f];
}

用的时候也很简单,

[favButton setTitleColor:[UIColor colorWithHexString:@"#666666"] forState:UIControlStateNormal];

这样就OK了.