Dynamic Theme Changing Challange

list.dart

import 'package:bytebank/models/transfer.dart';
import 'package:flutter/material.dart';
import 'package:scoped_model/scoped_model.dart';

import '../../main.dart';
import 'file:///C:/git/mo20-082020/bytebank/lib/screens/transfer/form.dart';

class TransfersList extends StatefulWidget {
  final List<Transfer> _transfers = List();

  @override
  State<StatefulWidget> createState() {
    return TransfersListState();
  }
}

class TransfersListState extends State<TransfersList> {
  @override
  Widget build(BuildContext context) {
    const _appBarTitle = 'Transfers';

//    return ScopedModelDescendant<DarkModeModel>(
//      builder: (context, child, model) {
    return Scaffold(
      body: ListView.builder(
        itemCount: widget._transfers.length,
        itemBuilder: (context, index) {
          final transfer = widget._transfers[index];
          return TransferItem(transfer);
        },
      ),
      appBar: AppBar(
        title: Text(_appBarTitle),
        actions: <Widget>[
          ScopedModelDescendant<DarkModeModel>(
            builder: (context, snapshot, model) {
              return IconButton(
                icon: Icon(Icons.lightbulb_outline),
                onPressed: () {
                  model.toggle();
                },
              );
            }
          ),
        ],
      ),
      floatingActionButton: FloatingActionButton(
        child: Icon(Icons.add),
        onPressed: () {
          final Future future = Navigator.push(
            context,
            MaterialPageRoute(
              builder: (context) {
                return TransferForm();
              },
            ),
          );
          future.then(
            (transferReceived) {
              debugPrint('arrived at then of the future');
              debugPrint('$transferReceived');
              if (transferReceived != null) {
                setState(
                  () => widget._transfers.add(transferReceived),
                );
              }
            },
          );
        },
      ),
//        );
//      }
    );
  }
}

class TransferItem extends StatelessWidget {
  final Transfer _transfer;

  TransferItem(this._transfer);

  @override
  Widget build(BuildContext context) {
    return Card(
      child: ListTile(
        leading: Icon(Icons.monetization_on),
        title: Text(_transfer.value.toString()),
        subtitle: Text(_transfer.accountNumber.toString()),
      ),
    );
  }
}

main.dart

import 'package:bytebank/screens/transfer/list.dart';
import 'package:flutter/material.dart';
import 'package:scoped_model/scoped_model.dart';

void main() => runApp(BytebankApp());

class BytebankApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return ScopedModel<DarkModeModel>(
      model: DarkModeModel(),
      child: ScopedModelDescendant<DarkModeModel>(
        builder: (context, child, model) => MaterialApp(
          theme: model.darkmode ? ThemeData.dark() : defaultTheme(),
          home: Scaffold(
            body: TransfersList(),
          ),
        ),
      ),
    );
  }
}

class DarkModeModel extends Model {
  bool darkmode = false;

  void toggle() {
    darkmode = !darkmode;
    debugPrint('Dark mode is now $darkmode');
    notifyListeners();
  }
}

ThemeData defaultTheme() {
  return ThemeData(
    primaryColor: Colors.green[900],
    accentColor: Colors.blueAccent[700],
    buttonTheme: ButtonThemeData(
      buttonColor: Colors.blueAccent[700],
      textTheme: ButtonTextTheme.primary,
    ),
  );
}