How to add shadow to UINavigationController

Question

I want to create a Slide Menu like in Path or Facebook with a shadow between my menu and the UINavigationController with all the content inside. I can add rounded corners to the layer but the shadow I apply to the layer is not shown. What is wrong with that code? It is working if I use a UIViewController instead of the UINavigationController... (The code is inside a view added as rootViewController to the UINavigationController)

The problem is that I don't want to loose the rounded borders of the UINavigationController

self.navigationController.view.layer.shadowPath = [UIBezierPath bezierPathWithRoundedRect:self.navigationController.view.bounds cornerRadius:self.navigationController.view.layer.cornerRadius].CGPath;
[self.navigationController.view.layer setMasksToBounds:YES];
[self.navigationController.view.layer setShadowColor:[UIColor blackColor].CGColor];
[self.navigationController.view.layer setShadowOffset:CGSizeMake(0, 0)];
[self.navigationController.view.layer setShadowOpacity:0.5];
[self.navigationController.view.layer setShadowRadius:3];
[self.navigationController.view.layer setCornerRadius:3];

Answer 1

In Swift3

self.navigationController?.view.layer.shadowOffset = CGSize(width: 0, height: 5)
self.navigationController?.view.layer.masksToBounds = true