CAGradientLayer with Rounded Top Corners (without using .mask) - objective-c

Question

I am looking to create a CAGradientLayer with rounded corners. I can't use .cornerRadius because I would like to round only the top two corners. Also, I cannot use .mask because I would like to take a screenshot of it afterwards and renderInContext does not support CALayer masks.
How can I either:
A: Create an CALayer with a gradient and two rounded corners without using masks
or
B: Take a screenshot similar to UIGraphicsGetImageFromCurrentImageContext, but respecting the mask.

Answer 1

I figured out a programmatic approach to doing this. It involves creating a rounded layer then drawing a square layer on top of it. You'll have to do some playing around with the gradient colors and positions to get something that looks good.
NOTE: Not sure if this solution will work for you given your requirement about masks
+ (void)makeGradientButton:(UIButton *)button {
// Create a rounded layer
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = button.bounds;
gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor blackColor] CGColor], (id)[[UIColor whiteColor] CGColor], nil];
gradient.cornerRadius = 8.0f;
// Now create a square layer that draws over the top
CAGradientLayer *gradient2 = [CAGradientLayer layer];
gradient2.frame = CGRectMake(0, 9, button.bounds.size.width, button.bounds.size.height-9);
gradient2.colors = [NSArray arrayWithObjects:(id)[[UIColor blackColor] CGColor], (id)[[UIColor redColor] CGColor], nil];
gradient2.cornerRadius = 0.0f;
[gradient setMasksToBounds:YES];
[button.layer insertSublayer:gradient atIndex:0];
[button.layer insertSublayer:gradient2 atIndex:1];
[button setBackgroundColor:[UIColor clearColor]];
}