dependencies:
  flutter:
    sdk: flutter
  amplify_datastore: any
  amplify_core: any

> amplify -v
4.41.2

> amplify init

? Enter a name for the project flutterapp
? Enter a name for the environment dev
? Choose your default editor: Visual Studio Code
? Choose the type of app that you're building flutter
Please tell us about your project
⚠️  Flutter project support in the Amplify CLI is in DEVELOPER PREVIEW.
Only the following categories are supported:
 * Auth
 * Analytics (Amazon Pinpoint only)
 * API (GraphQL only)
 * Storage
? Where do you want to store your configuration file? ./lib/
? Do you want to use an AWS profile? Yes

> amplify add api 

? Please select from one of the below mentioned services: GraphQL
? Provide API name: flutterapp
? Choose the default authorization type for the API API key
? Enter a description for the API key: 
? After how many days from now the API key should expire (1-365): 7
? Do you want to configure advanced settings for the GraphQL API Yes, I want to make some additional changes.
? Configure additional auth types? No
? Configure conflict detection? Yes
? Select the default resolution strategy Auto Merge
? Do you have an annotated GraphQL schema? No
? Choose a schema template: Single object with fields (e.g., “Todo” with ID, name, description)
? Do you want to edit the schema now? No

> amplify push
✔ Successfully pulled backend environment dev from the cloud.

Current Environment: dev

| Category | Resource name | Operation | Provider plugin   |
| -------- | ------------- | --------- | ----------------- |
| Api      | flutterapp    | Create    | awscloudformation |
? Are you sure you want to continue? Yes

> amplify codegen models

  void initState() {
    super.initState();
    AmplifyDataStore datastorePlugin =
        AmplifyDataStore(modelProvider: ModelProvider.instance);
    amplifyInstance.addPlugin(dataStorePlugins: [datastorePlugin]);
    amplifyInstance.configure(amplifyconfig);
  }

  void _addTodo() async {
    Todo newTodo = Todo(name: 'HOGE');
    await Amplify.DataStore.save(newTodo);
  }

import 'package:flutter/material.dart';
import 'package:amplify_core/amplify_core.dart';
import 'package:amplify_datastore/amplify_datastore.dart';
import 'package:flutter_app/amplifyconfiguration.dart';
import 'package:flutter_app/models/ModelProvider.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);
  final String title;
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  Amplify amplifyInstance = Amplify();
  @override
  void initState() {
    super.initState();
    AmplifyDataStore datastorePlugin =
        AmplifyDataStore(modelProvider: ModelProvider.instance);
    amplifyInstance.addPlugin(dataStorePlugins: [datastorePlugin]);
    amplifyInstance.configure(amplifyconfig);
  }

  void _addTodo() async {
    Todo newTodo = Todo(name: 'HOGE');
    await Amplify.DataStore.save(newTodo);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _addTodo,
        tooltip: 'Add',
        child: Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

Launching lib/main.dart on sdk gphone x86 in debug mode...
/xxx/flutter_app/android/app/src/debug/AndroidManifest.xml Error:
        uses-sdk:minSdkVersion 16 cannot be smaller than version 21 declared in library [:amplify_core] /xxx/flutter_app/build/amplify_core/intermediates/library_manifest/debug/AndroidManifest.xml as the library might be using APIs not available in 16
        Suggestion: use a compatible library with a minSdk of at most 16,
                or increase this project's minSdk version to at least 21,
                or use tools:overrideLibrary="com.amazonaws.amplify.amplify_core" to force usage (may lead to runtime failures)

FAILURE: Build failed with an exception.                                

* What went wrong:                                                      
Execution failed for task ':app:processDebugMainManifest'.              
> Manifest merger failed with multiple errors, see logs                 

* Try:                                                                  
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org                              

BUILD FAILED in 10s                                                     
Running Gradle task 'assembleDebug'...                                  
Running Gradle task 'assembleDebug'... Done                        13.0s
Exception: Gradle task assembleDebug failed with exit code 1

defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.myapp.flutter_app"
        minSdkVersion 21
        targetSdkVersion 30
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
    }