iOS UITableViewCell CornerRadius Constant - ios

Question

I am extending UITableView and overriding setBackgroundView to add a gradient to cell in a grouped style table view. All good so far...
In order to apply rounded corners to the cell, I set the cornerRadius to 10 which looks about right.
All is working well but I don't like the idea of hardcoding the cornerRadius. Is this constant somewhere in the Cocoa code base?
Example:
- (void) setBackgroundView:(UIView *)backgroundView{
NSLog(#"called setBackground");
NSLog(#"%f", backgroundView.layer.shadowRadius); //yields 0.00000
NSLog(#"%f", backgroundView.layer.cornerRadius); //yields 3.00000
CAGradientLayer *gradient = [CAGradientLayer layer];
[gradient setCornerRadius:10];
[gradient setMasksToBounds:YES];
[gradient setBorderWidth:0.8f];
[gradient setBorderColor:[[UIColor darkGrayColor] CGColor]];
gradient.frame = backgroundView.bounds;
gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor greenColor] CGColor], (id) [[UIColor colorWithRed:.05 green:.65 blue:.05 alpha:1] CGColor],(id)[[UIColor colorWithRed:.05 green:.65 blue:.05 alpha:1] CGColor], (id)[[UIColor colorWithRed:.05 green:.45 blue:.05 alpha:1] CGColor], nil];
gradient.locations = [NSArray arrayWithObjects: (id)[NSNumber numberWithFloat:0.10], (id)[NSNumber numberWithFloat:0.50], (id)[NSNumber numberWithFloat:0.50], (id)[NSNumber numberWithFloat:1.0], nil];
[backgroundView.layer insertSublayer:gradient atIndex:0];
[super setBackgroundView:backgroundView]; }