onSaveInstanceState () and onRestoreInstanceState ()

Question

I\'m trying to save and restore the state of an Activity using the methods onSaveInstanceState() and onRestoreInstanceState().

Answer 1

From the documentation Restore activity UI state using saved instance state it is stated as:

Instead of restoring the state during onCreate() you may choose to implement onRestoreInstanceState(), which the system calls after the onStart() method. The system calls onRestoreInstanceState() only if there is a saved state to restore, so you do not need to check whether the Bundle is null:

IMO, this is more clear way than checking this at onCreate, and better fits with single responsiblity principle.