Flutter: SpeechToTextProvider com formulário

Estou ficando louco com speech_to_text.

No meu aplicativo tenho vários formulários, cada um com vários arquivos TextFormFields. Para cada entrada devo anexar um microfone que me permita transcrever o que é dito. Eu tinha implementado tudo com basic SpeechToText, mas deu alguns problemas devido às diversas inicializações. Em seguida, modifiquei tudo mudando SpeechToTextProvidere me inspirando neste código disponibilizado pelo plugin .

No entanto, não posso garantir que o texto falado seja transcrito palavra por palavra na entrada. Isso SpeechToTexté tratado através do onResultparâmetro do evento listen, mas não está disponível no provedor!

Alguém pode me ajudar? Mil obrigados!

Aqui está o código de um formulário, para simplificar com apenas uma entrada:

class WeekForm extends StatefulWidget {
  const WeekForm({required this.week, super.key});

  final Week week;

  @override
  State<WeekForm> createState() => _WeekFormState();
}

class _WeekFormState extends State<WeekForm> {
  Week get week => widget.week;

  final _formKey = GlobalKey<FormState>(debugLabel: "WeekForm");

  final TextEditingController _learnedController = TextEditingController();
  String _lastTextChange = '';

  void _setLastTextChange(inputKey, lastText) {
    setState(() {
      _lastTextChange = lastText;
    });
  }

  void _saveLearn(week, appState) async {
    if (_formKey.currentState!.validate()) {
      week.learned = _learnedController.text;

      // save data to Firebase
      appState.setWeek(week);
    }
  }

  @override
  void initState() {
    ///fetched data from firebase showing on controller
    super.initState();
    _learnedController.text = week.learned ?? "";
    _setLastTextChange("learned", _learnedController.text);
  }

  @override
  Widget build(BuildContext context) {
    return Form(
      key: _formKey,
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[
          // Add TextFormFields and ElevatedButton here.
          Row(
            children: [
              Expanded(
                child: TextFormField(
                  controller: _learnedController,
                  decoration: const InputDecoration(
                    border: OutlineInputBorder(),
                  ),
                  onChanged: (value) {
                    _setLastTextChange("learned", value);
                  },
                ),
              ),
              SpeechProvider(
                key: const ValueKey("learned"),
                controller: _learnedController,
                lastInputChange: _lastTextChange,
                setLastInputChange: _setLastTextChange,
              ),
            ],
          ),
          Consumer<ApplicationState>(
            builder: (context, appState, _) => Align(
              alignment: Alignment.bottomRight,
              child: ElevatedButton(
                onPressed: () => _saveLearn(week, appState),
                child: const Text("Save"),
              ),
            ),
          ),
        ],
      ),
    );
  }
}

E aqui está o código para chamar SpeechToTextProvider:

import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:speech_to_text/speech_to_text_provider.dart';

class SpeechProvider extends StatefulWidget {
  const SpeechProvider({
    super.key,
    required this.controller,
    required this.lastInputChange,
    required this.setLastInputChange,
  });

  final TextEditingController controller;
  final String lastInputChange;
  final void Function(String, String) setLastInputChange;

  @override
  SpeechProviderState createState() => SpeechProviderState();
}

class SpeechProviderState extends State<SpeechProvider> {
  String lastWords = '';
  String lastStatus = '';

  late SpeechToTextProvider speechProvider;

  void startListening() {
    if (speechProvider.isAvailable && speechProvider.isNotListening) {
      lastWords = '';

      speechProvider.listen(
        // I want something like this!!! but this is available only in basic SpeechToText
        onResult: resultListener,
      );
    }
  }

  void stopListening() {
    if (speechProvider.isListening) {
      speechProvider.stop();
      widget.setLastInputChange((widget.key as ValueKey<dynamic>).value, widget.controller.text);
      setState(() {});
    }
  }

  /// This callback is invoked each time new recognition results are
  /// available after `listen` is called.
  void resultListener() {
    var result = speechProvider.lastResult;

    if (result!.finalResult) {
      widget.setLastInputChange((widget.key as ValueKey<dynamic>).value, widget.controller.text);
    } else {
      setState(() {
        lastWords = result.recognizedWords;
      });
      widget.controller.text = '${widget.lastInputChange} $lastWords';
    }
  }

  @override
  Widget build(BuildContext context) {
    speechProvider = Provider.of<SpeechToTextProvider>(context);

    if (speechProvider.isNotAvailable) {
      return const Center(
        child: Text('Speech recognition not available, no permission or not available on the device.'),
      );
    }
    return MicrophoneWidget(speechProvider.isListening, startListening, stopListening, key: UniqueKey());
  }
}

class MicrophoneWidget extends StatelessWidget {
  const MicrophoneWidget(this.isListening, this.startListening, this.stopListening, {super.key});

  final bool isListening;
  final void Function() startListening;
  final void Function() stopListening;

  @override
  Widget build(BuildContext context) {
    return TapRegion(
      onTapOutside: (tap) => isListening ? stopListening() : null,
      child: Padding(
        padding: const EdgeInsets.all(8.0),
        child: SizedBox(
          child: FloatingActionButton(
            onPressed: isListening ? stopListening : startListening,
            shape: const RoundedRectangleBorder(
              borderRadius: BorderRadius.all(Radius.circular(80.0)),
            ),
            child: Icon(isListening ? Icons.mic : Icons.mic_off),
          ),
        ),
      ),
    );
  }
}