SQLITE Android NullPointerException when updating data

Question

I am having a SQLITE Android problem.

I am using the same activity [CadastroCliente] to both Register & Update customers information; To define whether I want to update or register, I have a public static integer variable called UPDATE in the main menu [ListarClientes], which 0 = register and 1 = update.

So it goes like this:

1. the user clicks on "edit info"
2. I tell the register/update activity that the UPDATE variable value is 1, so it knows it's on editing mode.
3. the user type in the stuff he wants to update.

4. When he clicks the "save" button, this is the method I call:

           if (listarCliente.UPDATE == 0)
               this.cadastrar();
           if (listarCliente.UPDATE == 1)
               this.clienteDAO.updateData(listarCliente.ID_CLIENTE, nome, email);
   

And this is the error I get:

java.lang.NullPointerException: Attempt to invoke virtual method 'int android.database.sqlite.SQLiteDatabase.update(java.lang.String, android.content.ContentValues, java.lang.String, java.lang.String[])' on a null object reference 
at dao.ClienteDAO.updateData(ClienteDAO.java:104)
at com.financeiro.coolkey.financeiro_2.CadastroCliente.onOptionsItemSelected(CadastroCliente.java:138)

I am confused because when I call "clienteDAO.updateData" from ListarCliente activity it works like a charm. But when I send it to CadastroCliente, it returns this error. Any tips?

If it's lacking any info please tell me and I will definitely update! :)

Thanks in advance!!!

-

- EXTRA INFO:

dao.ClienteDAO.updateData(ClienteDAO.java:104)

public boolean updateData(long updateId, String nome, String email)
{
    ContentValues contentValues = new ContentValues();
    contentValues.put(DatabaseHelper.Clientes.NOME, nome);
    contentValues.put(DatabaseHelper.Clientes.EMAIL, email);

    return database.update(DatabaseHelper.Clientes.TABELA, contentValues, DatabaseHelper.Clientes._ID + "=" + updateId, null) > 0;
}

com.financeiro.coolkey.financeiro_2.CadastroCliente.onOptionsItemSelected(CadastroCliente.java:138)

this.clienteDAO.updateData(listarCliente.ID_CLIENTE, nome, email);

How the activity is started from the ListarClientes [main menu]:

        UPDATE = 1;
        startActivity(new Intent(ListarCliente.this, CadastroCliente.class));

Complete onClick method where the updateData is called:

@Override
public boolean onOptionsItemSelected(MenuItem item)
{
    int id = (int) item.getItemId();

    AdapterView.AdapterContextMenuInfo menuInfo = (AdapterView.AdapterContextMenuInfo)item.getMenuInfo();

    String nome = edtNome.getText().toString();
    String email = edtEmail.getText().toString();

    if (id == R.id.action_menu_salvar)
    {
        validacao = true;

        if (nome == null || nome.equals(""))
        {
            validacao = false;
            edtNome.setError(getString(R.string.mensagem_cadastro_erro));
        }

        if(email == null || email.equals(""))
        {
            validacao = false;
            edtEmail.setError(getString(R.string.mensagem_cadastro_erro));
        }

        if(validacao)
        {
            if (listarCliente.UPDATE == 0)
                this.cadastrar();
            if (listarCliente.UPDATE == 1)
                this.clienteDAO.updateData(listarCliente.ID_CLIENTE, nome, email);


            finish();
            startActivity(new Intent(this, ListarCliente.class));
        }
    }

    if (id == R.id.action_menu_sair)
    {
        finish();
        startActivity(new Intent(this, ListarCliente.class));
    }

    return super.onOptionsItemSelected(item);
}

WHERE clienteDAO is initialized:

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

    if (listarCliente.UPDATE == 0)
        setTitle("Cadastro de Clientes");
    else if (listarCliente.UPDATE == 1)
        setTitle("Editar Dados do cliente");


    clienteDAO = new ClienteDAO(this);


    edtNome = (EditText) findViewById(R.id.cadastro_edtNome);
    edtEmail = (EditText) findViewById(R.id.cadastro_edtEmail);
}

Answer 1

NullPointerException: Attempt to invoke virtual method

Means update method is called using non-initialized object. so make sure database is not null before calling update method