There's really no code snippet for this. I'm building an Android app in Android Studio in Kotlin with a main activity in both default portrait and lanscape modes. I'm using Android Studio auto-generated layout\activity_main.xml and layout-land\activity_main.xml layouts.
PROBLEM: When I rotate screens in the app, all widgets reset state. For example, I have a TextView, tvTitle, with a default hardcoded string, "Hello World". tvTitle normally changed to "News" while using the app in portrait mode. I then switched to landscape mode and tvTitle reverted to it's hardcoded default string, Hello. How can I retain the state of the app through rotations?
You might find the solution to your particular problem after understanding the Android mechanisms for saving the application state.
I suggest that you check out the official guide.