How to keep changed Int variable when reopening Activity?

Question

Java

The scenario is as follows: through Activity #1 I go ( startActivityForResult) to Activity #2, where the player turns on, in Activity #2 I press the turn button, the value turn_ok = 2 is assigned there, then returns ( setResult(RESULT_OK, intent);) Activity #1, the next time Activity #2 is opened, check for turn_ok value, if turn_ok = 2, then stop player playback.
In Activity #2, a variable is declared before onCreate: In Activity #2, when creating, a check is made in onCreate:
private int turn_ok;

if(turn_ok == 2){
            playlistManager.invokeStop();
            turn_ok = 1;
        }

When you click on the turn button in Activity #2, the following happens:

public void onClick_turn (View v){
        turn_ok = 2;
        Intent intent = new Intent();
        setResult(RESULT_OK, intent);
        finish();
    }

You need to save the changed variable (turn_ok = 2) the next time you open Activity #2 via startActivityForResult.
It turns out you need to somehow overwrite the variable.
I tried through putExtra, but the result is zero, since it is not yet known how to bring it to one variable.
How to implement this?

Answer 1

To save the state of the activity or any values ​​use SaveInstanceState or SharedPreference