btOK.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            Cursor cs = data.rawQuery(sql_selectLogin, new String[] {
                    username, password });
            // TODO Auto-generated method stub
            if (cs.getCount() == 1)
                Toast.makeText(
                        MainActivity.this,
                        "You just have succesfull logined by username= "
                                + edit_username.getText().toString(),
                        Toast.LENGTH_SHORT).show();

            else

                Toast.makeText(MainActivity.this, "You fail login",
                        Toast.LENGTH_SHORT).show();

        }
    });`