What error is this? "Could not find method schedule (View) in"

I'm calling a method, when I click the button and this error appears, but I do not know what it means:

  

java.lang.IllegalStateException: Could not find method (View) in a parent or ancestor Context for android: onClick attribute defined on view class android.support.v7.widget.AppCompatButton with id 'btnAgendar'

Follow my code

public class AgendamentoActivity extends AppCompatActivity {

private ProfissionalPojo p;
private ListView listAgendamentos;
private Spinner spinnerHorario;

private String dadoHora;
private StringCharacterIterator editText;
private Calendar myCalendar;
private String diaAgenda;

private int idusuario;
private String nome;
private String sobrenome;
private String dia;
private String hora;
private Button botaoAgenda;

//private horario adapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_agendamento);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    Bundle extra = getIntent().getExtras();

    if(extra != null){
        idusuario = extra.getInt("idusuario");
        nome = extra.getString("nome");
        sobrenome = extra.getString("sobrenome");
    }
    Toast.makeText(this, "id usuario "+idusuario, Toast.LENGTH_SHORT).show();

    final Calendar myCalendar = Calendar.getInstance();

    p = (ProfissionalPojo) getIntent().getSerializableExtra("pro");

    agendar(p.getIdprofissional(), idusuario, nome, sobrenome, dia, hora);

    listAgendamentos = ((ListView)findViewById(R.id.lvAgendamentos));
    botaoAgenda = ((Button) findViewById(R.id.btnAgendar));

    EditText editText = ((EditText)findViewById(R.id.edtDia));

    spinnerHorario = (Spinner) findViewById(R.id.spHorario);

    ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
            R.array.spHorario, android.R.layout.simple_spinner_item);
    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinnerHorario.setAdapter(adapter);

    spinnerHorario.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener(){

        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {

            if(i == 0){
                //Toast.makeText(getBaseContext(), "8:00 - 9:00", Toast.LENGTH_LONG).show();
                String dadoHora = "8:00 - 9:00";
            }else if (i == 1){
                //Toast.makeText(getBaseContext(), "9:00 - 10:00", Toast.LENGTH_LONG).show();
                String dadoHora = "9:00 - 10:00";
            }else if (i == 2){
                //Toast.makeText(getBaseContext(), "10:00 - 11:00", Toast.LENGTH_LONG).show();
                String dadoHora = "10:00 - 11:00";
            }else if (i == 3){
                //Toast.makeText(getBaseContext(), "11:00 - 12:00", Toast.LENGTH_LONG).show();
                String dadoHora = "11:00 - 12:00";
            }else if (i == 4){
                //Toast.makeText(getBaseContext(), "12:00 - 13:00", Toast.LENGTH_LONG).show();
                String dadoHora = "12:00 - 13:00";
            }else if (i == 5){
                //Toast.makeText(getBaseContext(), "13:00 - 14:00", Toast.LENGTH_LONG).show();
                String dadoHora = "13:00 - 14:00";
            }else if (i == 6){
                //Toast.makeText(getBaseContext(), "14:00 - 15:00", Toast.LENGTH_LONG).show();
                String dadoHora = "14:00 - 15:00";
            }else if (i == 7){
                //Toast.makeText(getBaseContext(), "15:00 - 16:00", Toast.LENGTH_LONG).show();
                String dadoHora = "15:00 - 16:00";
            }else if (i == 8){
                //Toast.makeText(getBaseContext(), "16:00 - 17:00", Toast.LENGTH_LONG).show();
                String dadoHora = "16:00 - 17:00";
            }else if (i == 9){
                //Toast.makeText(getBaseContext(), "17:00 - 18:00", Toast.LENGTH_LONG).show();
                String dadoHora = "17:00 - 18:00";
            }

            dadoHora = spinnerHorario.getSelectedItem().toString();
            exibeHora();

        }


        @Override
        public void onNothingSelected(AdapterView<?> adapterView) {

        }

    });

    final DatePickerDialog.OnDateSetListener date = new DatePickerDialog.OnDateSetListener() {

        @Override
        public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
            // TODO Auto-generated method stub
            myCalendar.set(Calendar.YEAR, year);
            myCalendar.set(Calendar.MONTH, monthOfYear);
            myCalendar.set(Calendar.DAY_OF_MONTH, dayOfMonth);
            updateLabel(myCalendar);

        }

    };

    editText.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            new DatePickerDialog(AgendamentoActivity.this, date, myCalendar
                    .get(Calendar.YEAR), myCalendar.get(Calendar.MONTH),
                    myCalendar.get(Calendar.DAY_OF_MONTH)).show();

        }
    });

    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
    String time = sdf.format(myCalendar.getTime());
}

public void exibeDia(){
    final TextView tvDia = ((TextView) findViewById(R.id.tvDia));
    tvDia.setText(diaAgenda);
    dia = tvDia.toString();
}

public void exibeHora(){
    final TextView tvHora = ((TextView) findViewById(R.id.tvHora));
    tvHora.setText(dadoHora);
    hora = tvHora.toString();
}


private void updateLabel(Calendar myCalendar) {
    SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
    diaAgenda = sdf.format(myCalendar.getTime());
    exibeDia();
}

public void agendar(final String idprofissional, int idusuario, String nome, String sobrenome, String dia, String hora) {

    Log.d("TAG", "idpro " + idprofissional + " idusuario " + idusuario + " nome " +nome+ " sobrenome " +sobrenome+ " dia " + dia + " hora " + hora);

}
}