flutter_app/lib/main.dart

import 'dart:ffi';
import 'package:ffi/ffi.dart';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'model.dart';
import 'views/profilemgrview.dart';

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

class Flwtch extends StatefulWidget {
  final Key flwtch = GlobalKey();

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

class FlwtchState extends State<Flwtch> {
  final TextStyle biggerFont = const TextStyle(fontSize: 18);

  DynamicLibrary library;
  AppModel appStatus;

  @override
  Widget build(BuildContext context) {
    library = DynamicLibrary.open("libCwtch.so");
    appStatus = AppModel(library: library);

    var startCwtchC = library.lookup<NativeFunction<start_cwtch_function>>("StartCwtch");
    // ignore: non_constant_identifier_names
    final StartCwtch = startCwtchC.asFunction<StartCwtchFn>();

    var cwtchDir = "/home/sarah/.cwtch/dev/";
    StartCwtch(Utf8.toUtf8(cwtchDir), cwtchDir.length);

    return Provider<FlwtchState>(
        create: (_) => this,
        child: MaterialApp(
          title: 'Flutter Demo',
          theme: ThemeData(
            // This is the theme of your application.
            //
            // Try running your application with "flutter run". You'll see the
            // application has a blue toolbar. Then, without quitting the app, try
            // changing the primarySwatch below to Colors.green and then invoke
            // "hot reload" (press "r" in the console where you ran "flutter run",
            // or simply save your changes to "hot reload" in a Flutter IDE).
            // Notice that the counter didn't reset back to zero; the application
            // is not restarted.
            primarySwatch: Colors.blue,
            // This makes the visual density adapt to the platform that you run
            // the app on. For desktop platforms, the controls will be smaller and
            // closer together (more dense) than on mobile platforms.
            visualDensity: VisualDensity.adaptivePlatformDensity,
            primaryColor: Color(0xFF4B3557),
            canvasColor: Color(0xFFB09CBC),
            accentColor: Color(0xFFD01972),
          ),
          home: ProfileMgrView(),
      ));
  }
}