Update text in TextView through an OnsharedPreferenceChangeListener

Question

I have tried different things for quite some hours now, but I cannot seem to wrap my head around how to update a TextView when a user inputs a new text through an EditTextPreference in Android.

I use a switch statement in the onSharedPreferenceChanged method, inside an anonymous listener class. However, when i set player1View.setText(value), nothing happens. Is there an easier way of accomplishing this task – namely updating the textView through user input?

Here is the bit of code I cannot make work:

public class SettingsActivity extends AppCompatActivity
{
        private TextView player1View;
        private TextView player2View;
        private SharedPreferences.OnSharedPreferenceChangeListener listener;

@Override
protected void onCreate(Bundle savedInstanceState)
{
    player1View = findViewById(R.id.player1);
    player2View = findViewById(R.id.player2);
    super.onCreate(savedInstanceState);
    getSupportFragmentManager().beginTransaction().replace(android.R.id.content, new SettingsFragment()).commit();
    createListener();
}

private void createListener()
{
    listener = new SharedPreferences.OnSharedPreferenceChangeListener()
    {
        @Override
        public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key)
        {
            EditTextPreference etp = (EditTextPreference) sharedPreferences;
            String value = sharedPreferences.getString("player_one", "NULL");
            switch(key)
            {
                case "switch_setting1":
                    //Do something
                    break;
                case "player1_key":
                    player1View.setText(value);
                    break;
                case "player2_key":
                    player2View.setText(value);
                    break;
            }
        }
    };
    PreferenceManager.getDefaultSharedPreferences(getApplicationContext())
            .registerOnSharedPreferenceChangeListener(listener);
}
}

The screenshots below should emphasize more clearly what i mean. The fields I want to change are the ones named "Player 1" and "Player 2", and to accomplish that the user inputs new names through settings as shown.

Screenshots from the Android Emulator

Answer 1

Try maybe instead of:

String value = sharedPreferences.getString("player_one", "NULL");

This:

String value = sharedPreferences.getString("player_one", null);

or you might want to create two String variables(value, value2 for example), one for "player_one" and the other for "player_two" if you have forgot to add. I don't know exactly what you are trying to build.