When creating a custom transition between two screens in a Flutter app, what key elements are involved?

When creating a custom transition between two screens in Flutter, key elements involve using the PageRouteBuilder and Hero widget. PageRouteBuilder allows you to define custom transitions, and the Hero widget facilitates smooth transitions for shared elements between screens. This approach ensures a visually appealing and seamless user experience during screen transitions. Understanding how to implement custom transitions is essential for creating polished and professional Flutter applications.