Não consigo fazer funcionar o menu na barra de cima

Já testei e refiz, mas não consigo solucionar. Aparece nada no menu de cima.

Meus códigos:

FormularioActivity.java
public class FormularioActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_formulario);

        Button botaoSalvar = (Button) findViewById(R.id.formulario_salvar);
        botaoSalvar.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Toast.makeText(FormularioActivity.this, "Botão Clicado!", Toast.LENGTH_SHORT).show();
                finish();
            }
        });

    }

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


}

menu_formulario.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <item
        android:id="@+id/menu_formulario_ok"
        android:title="Ok"
        android:icon="@drawable/ic_confirmar"
        app:showAsAction="always"/>
</menu>