Remove arrow of "Open In..." menu on iOS

Question

I'm positioning an "Open In..." menu in the center of the screen on my app. The problem is that iOS adds an arrow to the bottom of the rectangle. Is it possible to not have an arrow?

If I use CGRectZero I don't have the arrow, but I can't position the menu to the center. Here is the code:

CGPoint centerPoint = [Rhodes sharedInstance].window.center;
CGRect centerRec = CGRectMake(centerPoint.x, centerPoint.y, 0, 0);
BOOL isValid = [docController presentOpenInMenuFromRect:centerRec inView:[Rhodes sharedInstance].window animated:YES];