Detailed explanation and use of UINavigationController for IOS learning: adding UIBarButtonItem

1. How to use UINavigationController navigation controller UINavigationController can be translated into navigation controller, which is often used in iOS. Let's see how it is used: The following diagram shows the flow of the navigation controller. On the far left is the root view. When the user clicks the General item, the General view will slide into the screen; when the user continues to click the Auto-Lock item, the Auto-Lock view will slide into the screen. Correspondingly, in