生成纯色色块

//色块生成图片
- (UIImage *)buttonImageFromColor:(UIColor *)color{

    CGRect rect = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetFillColorWithColor(context, [color CGColor]);
    CGContextFillRect(context, rect);
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return img;
}