java - setText on button from another activity android

I have a problem, I want to click on the list, calling a new activity and rename the button to another name.

I tried several things, nothing worked, can someone please help me?

My class EditarTimes:

private AdapterView.OnItemClickListener selecionarTime = new AdapterView.OnItemClickListener() {

    public void onItemClick(AdapterView arg0, View arg1, int pos, long id) {
        t = times.get(pos);


        CadastroTimes cad = new CadastroTimes();
        CadastroTimes.salvar.setText("Alterar");
        Intent intent = new Intent(EditarTimes.this, CadastroTimes.class);
        startActivity(intent);


    }

};

public class CadastroTimes extends AppCompatActivity {

    private Time t;
    private timeDatabase db;
    private EditText edID;
    private EditText edNome;
    public Button salvar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

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

        edID = (EditText) findViewById(R.id.edID);
        edNome = (EditText) findViewById(R.id.edNome);
        db = new timeDatabase(getApplicationContext());
        salvar = (Button) findViewById(R.id.btnCadastrar);
        salvar.setText("Cadastrar");
        String newString;
        if (savedInstanceState == null) {

            Bundle extras = getIntent().getExtras();
            if(extras == null) {
                newString= null;
            } else {
                newString= extras.getString("Alterar");
            }
        } else {
            newString= (String) savedInstanceState.getSerializable("Alterar");
        }


        //button in CadastroTimes activity to have that String as text
        System.out.println(newString + " AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
        salvar.setText(newString);
    }

    public void salvarTime(View v) {
        t = new Time();
        t.setNome(edNome.getText().toString());

        if (salvar.getText().equals("Alterar")) {

            db.atualizar(t);
            exibirMensagem("Time atualizado com sucesso!");
        } else {
            db.salvar(t);
            exibirMensagem("Time cadastrado com sucesso!");
        }

        Intent intent = new Intent(this, EditarTimes.class);
        startActivity(intent);


    }


    private void limparDados() {
        edID.setText("");
        edNome.setText("");
        edNome.requestFocus();
    }

    private void exibirMensagem(String msg) {

        Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();
    }

}

public class EditarTimes extends AppCompatActivity {

    private Time t;
    private List times;
    private timeDatabase db;

    private ListView lvTimes;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_editar_times);

        lvTimes = (ListView) findViewById(R.id.lvTimes);
        lvTimes.setOnItemClickListener(selecionarTime);
        lvTimes.setOnItemLongClickListener(excluirTime);

        times = new ArrayList();
        db = new timeDatabase(getApplicationContext());
        atualizarLista();
    }

    private void excluirTime(final int idTime) {


        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("Excluir time?")

                .setIcon(android.R.drawable.ic_dialog_alert)
                .setMessage("Deseja excluir esse time?")
                .setCancelable(false)
                .setPositiveButton(getString(R.string.sim),
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                if (db.deletar(idTime)) {
                                    atualizarLista();
                                    exibirMensagem(getString(R.string.msgExclusao));
                                } else {

                                    exibirMensagem(getString(R.string.msgFalhaExclusao));
                                }

                            }
                        })
                .setNegativeButton(getString(R.string.nao),
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                dialog.cancel();
                            }

                        });
        builder.create();
        builder.show();

        atualizarLista();

    }

    private void atualizarLista() {


        times = db.listAll();
        if (times != null) {
            if (times.size() > 0) {
                TimeListAdapter tla = new TimeListAdapter(
                        getApplicationContext(), times);
                lvTimes.setAdapter(tla);
            }

        }


    }

    private AdapterView.OnItemClickListener selecionarTime = new AdapterView.OnItemClickListener() {

        public void onItemClick(AdapterView arg0, View arg1, int pos, long id) {
            t = times.get(pos);

            Intent intent = new Intent(EditarTimes.this, CadastroTimes.class);
            String strName = "Alterar";
            intent.putExtra("Alterar", strName);

            startActivity(intent);




            //preecherDados(t);

        }

    };


    private AdapterView.OnItemLongClickListener excluirTime = new AdapterView.OnItemLongClickListener() {

        public boolean onItemLongClick(AdapterView arg0, View arg1,
                                       int pos, long arg3) {
            excluirTime(times.get(pos).getId());
            return true;
        }



    };

    /*private void preecherDados(Time time) {
        edID.setText(String.valueOf(time.getId()));
        edNome.setText(time.getNome());
    }*/

    private void exibirMensagem(String msg) {
        Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();
    }


    public void telaCadastrar(View view) {
        Intent intent = new Intent(this, CadastroTimes.class);
        startActivity(intent);
    }

    public void botaoSair(View view) {
        Intent intent = new Intent(this, TelaInicial.class);
        startActivity(intent);
    }

}