通过十六进制创建 uicolor

+ (UIColor *)colorWithHex:(int)hexValue alpha:(CGFloat)alpha{
    return [UIColor colorWithRed:((float)((hexValue & 0xFF0000) >> 16))/255.0
                           green:((float)((hexValue & 0xFF00) >> 8))/255.0
                            blue:((float)(hexValue & 0xFF))/255.0
                           alpha:alpha];
}
+ (UIColor *)colorWithHex:(int)hexValue{
    return [UIColor colorWithHex:hexValue alpha:1.0];
}