How was the state of the fragments preserved before the advent of the ViewModel and LiveData?

Question

Android

The official guide for the ViewModel gives this example: an activity, in it a fragment with a list, and another fragment to display the element that is selected in the list.
How to support screen rotation without using ViewModel and LiveData? Those. How was it before 2017?

Answer 1

Just as it is done now where these components are not used.
onSaveInstanceState/onRestoreInstanceState +Icepick, retain fragment, not killing activity when changing configuration + onConfigurationChanged, replacing fragments with controllers (Conductor).