How to use Sharedpreferences from Android in this case?

Question

I am trying to save a display state, where when you press the robot button, a message "True" appears and changes the icon to a person and when I press the person’s icon back to the robot icon and has a message "false"I would like to use Sharedpreference to save the last display state, I would like to know where I am missing, follow the code below:

public class MainActivity extends AppCompatActivity {

    TextView testeT;
    boolean valorBooleano = false;
    SharedPreferences preferences;
    SharedPreferences.Editor editor;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        testeT = findViewById(R.id.text_teste);
        testeT.setText(" " + valorBooleano);

        preferences = getSharedPreferences("minhapreferencia", MODE_PRIVATE);
        preferences.getBoolean("chave", valorBooleano);
        editor = preferences.edit();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu, menu);
        return super.onCreateOptionsMenu(menu);

    }

    @Override
    public boolean onPrepareOptionsMenu(Menu menu) {
        if (valorBooleano == false) {
            menu.findItem(R.id.man).setVisible(true);
            menu.findItem(R.id.robot).setVisible(false);
        } else {
            menu.findItem(R.id.man).setVisible(false);
            menu.findItem(R.id.robot).setVisible(true);
        }


        return super.onPrepareOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case (R.id.man):
                invalidateOptionsMenu();
                testeT.setText(" " + valorBooleano);
                valorBooleano = true;
                break;
            case (R.id.robot):
                invalidateOptionsMenu();
                testeT.setText(" " + valorBooleano);
                valorBooleano = false;
                break;
        }

        return super.onOptionsItemSelected(item);


    }

    @Override
    protected void onPause() {
        super.onPause();
        if (preferences.contains("chave")){
            editor.putBoolean("chave", valorBooleano);
            editor.commit();
        }

    }
}

Answer 1

The error I have identified is that you are initiating Bostone value as false, and this does not change throughout the cycle. So what you need to do is change the initialization of your Boolean value and your onCreate so:

//apenas declare a variavel
boolean valorBooleano;

@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    testeT = findViewById(R.id.text_teste);


    preferences = getSharedPreferences("minhapreferencia", MODE_PRIVATE);
    //aqui o valorBooleano é incializado com a sharedpreferences, se não possuir valor atribuido a ela, então retornará false;
    valorBooleano = preferences.getBoolean("chave", false);
    //agora que o valorBooleano tá inicializado pode enviar o valor dele para o TextView
    testeT.setText(" " + valorBooleano);
    editor = preferences.edit();
}

I believe that only these 3 modifications will already do what you want. I hope to have helped.