Transitions happen when a view is added or removed from the view tree. In SwiftUI there is no addSubview(_:). Instead, you can only add and remove views through the combination of a state change and using an if statement (or switch or ForEach).
Every year Apple introduces new features to the system, and sometimes they have to deprecate some old APIs to make room for the new ones, learn how to handle these changes.
Starting with iOS 13, we can use quick actions to give users access to our app's functionality directly from the home screen, when they touch and hold the app icon.