Não estou conseguindo navegar entre telas, acredito que a tela seja no "Navigator.pop()". Alguém me ajuda?

class FormularioDeTransferencia extends StatelessWidget {
  final TextEditingController _controladorCampoNumeroConta =
      TextEditingController();
  final TextEditingController _controladorCampoValor = TextEditingController();

  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text('Criando Transferencia'),
        ),
        body: Column(
          children: <Widget>[
            Editor(
              controlador: _controladorCampoNumeroConta,
              rotulo: 'Número da Conta',
              dica: '0000',
            ),
            Editor(
              controlador: _controladorCampoValor,
              rotulo: 'Valor',
              dica: '00.00',
              icone: Icons.monetization_on,
            ),
            RaisedButton(
              child: Text('Confirmar'),
              onPressed: () {
                final int numeroConta =
                    int.tryParse(_controladorCampoNumeroConta.text);
                final double valor =
                    double.tryParse(_controladorCampoValor.text);

                if (numeroConta != null && valor != null) {
                  final tranferenciaCriada = Transferencia(valor, numeroConta);
                  debugPrint('Criando transferencia');
                  debugPrint('$tranferenciaCriada');

                  BuildContext context;
                  Navigator.pop(context, tranferenciaCriada);
                }
              },
            ),
          ],
        ));
  }
}

Abaixo é o erro que aparece

═══════ Exception caught by gesture ═══════════════════════════════════════════ The following NoSuchMethodError was thrown while handling a gesture: The method 'findAncestorStateOfType' was called on null. Receiver: null Tried calling: findAncestorStateOfType()

When the exception was thrown, this was the stack

#0 Object.noSuchMethod (dart:core-patch/object_patch.dart:54:5)

#1 Navigator.of _package:flutter/…/widgets/navigator.dart:2706

#2 Navigator.pop_______________________________________________________________________________________________package:flutter/…/widgets/navigator.dart:2592

#3 FormularioDeTransferencia.build._package:bytebank/main.dart:55

#4 InkResponseState.handleTap_____________________________________________________________________________package:flutter/…/material/ink_well.dart:991 ... Handler: "onTap" Recognizer: TapGestureRecognizer#014ea debugOwner: GestureDetector state: possible won arena finalPosition: Offset(226.0, 304.0) finalLocalPosition: Offset(67.8, 6.0) button: 1 sent tap down ════════════════════════════════════════════════════════════════════════════════