protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.login);
    setupVariables();
}

private void setupVariables() {
    username = (EditText) findViewById(R.id.username);
    password = (EditText) findViewById(R.id.password);
    login = (Button) findViewById(R.id.button);

}

public void Login(View view) {
    if (username.getText().toString().equals("admin") && password.getText().toString().equals("secret")) {
        /* switches activity if the username and password matches the string */
    }
    else {

    }
}