@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_login);
    etLogin = (EditText) findViewById(R.id.etLogin);
    etPassword = (EditText) findViewById(R.id.etPassword);
    btnJoin = (Button) findViewById(R.id.btnJoin);

    String username = etLogin.getText().toString();
    String password = etLogin.getText().toString();
    final String url = "https://IpAddress:Port/index.php/api/user";
    final AsyncHttpClient client = new AsyncHttpClient();
    client.setBasicAuth(username,password, new AuthScope("IP", Port, AuthScope.ANY_REALM));
    client.addHeader("Authorization", "Basic " + Base64.encodeToString((username+":"+password).getBytes(),Base64.DEFAULT));


    btnJoin.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {


            client.get(url, new AsyncHttpResponseHandler() {
                @Override
                public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {

                    Log.d("App", "Connected");

                }

                @Override
                public void onFailure(int statusCode, Header[] headers, byte[] responseBody, Throwable error) {
                    Log.d("App","Upload Failed!");
                    Log.d("App","Error Message: " + error.getMessage());
                    Log.d("App", "Error Cause: " + error.getCause());
                }
            });
        }
    });