- (UIImage *)gradientImageFromColors:(NSArray *)colors startPoint:(CGPoint)startPoint endPoint:(CGPoint)endPoint frame:(CGRect)frame{
  NSMutableArray *mutColors = [NSMutableArray array];
  for (UIColor *color in colors) {
    [mutColors addObject:(id)color.CGColor];
  }
  UIGraphicsBeginImageContextWithOptions(frame.size, YES, 1);
  CGContextRef context = UIGraphicsGetCurrentContext();
  CGContextSaveGState(context);
  CGColorSpaceRef colorSpace = CGColorGetColorSpace([[colors lastObject] CGColor]);
  CGGradientRef gradient = CGGradientCreateWithColors(colorSpace, (CFArrayRef)mutColors, NULL);
  CGPoint start = startPoint;
  CGPoint end = endPoint;
  CGContextDrawLinearGradient(context, gradient, start, end,
                              kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation);
  UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
  CGGradientRelease(gradient);
  CGContextRestoreGState(context);
  CGColorSpaceRelease(colorSpace);
  UIGraphicsEndImageContext();
  return image;
}