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copied!<p>The Storyboard image is a little misleading here.</p> <p>When you segue to B, <em>actually</em> you are segueing to the B/C combo as NavControllers always have at least one viewController in their stack (which is their <code>topViewController</code> and their <code>[viewControllers objectAtIndex:0]</code>).</p> <p>So you do have a relationship directly from A to C.</p> <p>How you access that controller depends on whether your segue is <em>modal</em> or <em>push</em>. In your case it is modal, but I will describe both so you can see the difference.</p> <p>In either case, to pass data to C, you need to declare a property in it's header file </p> <pre><code> @interface CviewController: UIViewContrller @property (assign) int dataFromA; @end </code></pre> <p><strong>push segue</strong> </p> <p>In a push segue, it is actually C that is the destinationViewController, not B. In fact the push segue is governed by B, which is the UINavigationController for both A and C. The code behind the push segue is of the form<br> <code>[self.navigationController pushViewController:otherViewController];</code></p> <p>In AviewController's prepareForSegue:</p> <pre><code> - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { CviewController* controller = segue.destinationViewController; [controller setDataFromA:self.data]; } </code></pre> <p>It is <em>possible</em> in the storyboard to make a push segue line between two viewControllers that do <em>not</em> share a common UINavigationController. However when you run this you will get a crash error:</p> <blockquote> <p>'Could not find a navigation controller for segue 'pushC'. Push segues can only be used when the source controller is managed by an instance of UINavigationController.'</p> </blockquote> <p>Behind every good push segue lies a Navigation Controller.</p> <p><strong>modal segue</strong> </p> <p>The code hiding behind a modal Segue is the UIViewController method<br> <code>- (void)presentViewController:(UIViewController *)viewControllerToPresent</code> </p> <p>In a modal segue to a NavController/ViewController combo, the destination viewController is whatever the segue line points to. If it points to a viewController, that is the segue.destinationController (and the UINavigationController will be ignored, which is not what you want here); if it points to a UINavigationController, as in this case, <em>that</em> will be it's destinationController. But it is still straightforward to access the viewController, as it will be the navigation Controller's topViewController.</p> <p>In AviewController's prepareForSegue:</p> <pre><code>- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { CviewController* controller = (CviewController*)[[segue destinationViewController] topViewController]; [controller setDataFromA:self.data]; } </code></pre> <p>Note that in this case we have to use old-style [[message passing] syntax]. If we use modern.property.syntax we get a compile error. That's because the program does not know the type of desinationViewController, and refuses to accept topViewController as a property of an unknown type. But it <em>is</em> happy to [send [real messages]] to an unknown type. We also have to (typecast*) to avoid compiler warnings. </p>

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