Instance Method

showViewController:sender:

Presents a view controller in a primary context.

Declaration

- (void)showViewController:(UIViewController *)vc sender:(id)sender;

Parameters

vc

The view controller to display.

sender

The object that initiated the request.

Discussion

You use this method to decouple the need to display a view controller from the process of actually presenting that view controller onscreen. Using this method, a view controller does not need to know whether it is embedded inside a navigation controller or split-view controller. It calls the same method for both. The UISplitViewController and UINavigationController classes override this method and handle the presentation according to their design. For example, a navigation controller overrides this method and uses it to push vc onto its navigation stack.

The default implementation of this method calls the targetViewControllerForAction:sender: method to locate an object in the view controller hierarchy that overrides this method. It then calls the method on that target object, which displays the view controller in an appropriate way. If the targetViewControllerForAction:sender: method returns nil, this method uses the window’s root view controller to present vc modally.

You can override this method in custom view controllers to display vc yourself. Use this method to display vc in a primary context. For example, a container view controller might use this method to replace its primary child. Your implementation should adapt its behavior for both regular and compact environments.