Use Supabase with Flutter

Help me add Supabase to my Flutter project. Create a Supabase project at
database.new and run the instruments table SQL. Then:
1. Run `flutter create my_app` to scaffold the app.
2. Add `supabase_flutter: ^2.0.0` to `pubspec.yaml`.
3. Initialize Supabase in `lib/main.dart` with your project URL and publishable
   key.
4. Replace the default app with a `FutureBuilder` and `ListView` to query and
   display the instruments table.
5. Run `flutter run` to start the app.

REFERENCE
https://supabase.com/docs/guides/getting-started/quickstarts/flutter.md

1. Create a Supabase project

To start, you need a Supabase project.

Create a new Supabase project from the Dashboard of any organization you belong to.

2. Set up your database

When your Supabase project is up and running, create an instruments table with some sample data. Then set only the privileges each Postgres role needs, add Row Level Security (RLS) for enhanced security for database data by default, and create an RLS policy to make the data in the table publicly readable.

Do these steps within your project's dashboard by copying and running the snippet in your project's SQL Editor.

-- Create the table
create table instruments (
  id bigint primary key generated always as identity,
  name text not null
);

-- Insert sample data into the table
insert into instruments (name)
values
  ('violin'),
  ('viola'),
  ('cello');

-- Grant the privileges the role needs, which is read access
grant select on public.instruments to anon;

-- Enable row level security for the table
alter table instruments enable row level security;

-- Create a policy to allow the anon role to read from the instruments table
create policy "public can read instruments"
on public.instruments
for select to anon
using (true);

3. Create a Flutter app

Create a Flutter app using the flutter create command.

flutter create my_app

4. Set up AI tooling (optional)

Supabase provides two ways to give AI tools context about your project: Agent Skills, which give your AI coding agent procedural knowledge, and the MCP server, which connects AI assistants to your Supabase project directly.

Agent Skills

Agent Skills is a curated set of instructions that give your AI agent procedural knowledge about working with Supabase.

Install them so your AI coding agent can produce more accurate, reliable code using current Supabase patterns, such as authentication, server-side rendering, and database migrations, rather than relying solely on training data.

Installing Agent Skills

To install, run the following command in the root of your project:

npx skills add supabase/agent-skills

Supabase MCP server

The Supabase MCP server connects AI assistants to Supabase, so they can inspect your schema and act on your projects on your behalf. Find out how to add it to your client in the MCP docs.

5. Install the Supabase client library

The fastest way to get started is to use the supabase_flutter client library which provides a convenient interface for working with Supabase from a Flutter app.

Open the pubspec.yaml file inside your Flutter app and add supabase_flutter as a dependency.

supabase_flutter: ^2.0.0

6. Initialize the Supabase client

Open lib/main.dart and edit the main function to initialize Supabase using your project URL and publishable key, which you can get from the helper below, or from the project Connect panel:

import 'package:supabase_flutter/supabase_flutter.dart';

Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();

  await Supabase.initialize(
    url: 'YOUR_SUPABASE_URL',
    publishableKey: 'YOUR_SUPABASE_PUBLISHABLE_KEY',
  );
  runApp(MyApp());
}

Get API details

To interact with data in database tables, you use the client libraries that wrap the auto-generated Data API endpoints, authenticating using the Project URL and key from the project Connect dialog.

Project URL: https://<project-ref>.supabase.co (find yours in the dashboard)

Publishable key: sb_publishable_... (find yours in the dashboard)

7. Query data from the app

Use a FutureBuilder to fetch the data when the home page loads and display the query result in a ListView.

Replace the default MyApp and MyHomePage classes with the following code.

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      title: 'Instruments',
      home: HomePage(),
    );
  }
}

class HomePage extends StatefulWidget {
  const HomePage({super.key});

  @override
  State<HomePage> createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  final _future = Supabase.instance.client
      .from('instruments')
      .select();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: FutureBuilder(
        future: _future,
        builder: (context, snapshot) {
          if (snapshot.hasError) {
            return Center(child: Text('Error loading instruments: ${snapshot.error}'));
          }
          if (!snapshot.hasData) {
            return const Center(child: CircularProgressIndicator());
          }
          final instruments = snapshot.data!;
          return ListView.builder(
            itemCount: instruments.length,
            itemBuilder: ((context, index) {
              final instrument = instruments[index];
              return ListTile(
                title: Text(instrument['name']),
              );
            }),
          );
        },
      ),
    );
  }
}

8. Start the app

Run your app on a platform of your choosing! By default an app should launch in your web browser.

Note that supabase_flutter is compatible with web, iOS, Android, macOS, and Windows apps. Running the app on macOS requires additional configuration to set the entitlements.

flutter run

9. Setup deep links (optional)

Many sign in methods require deep links to redirect the user back to your app after authentication. Read more about setting deep links up for all platforms (including web) in the Flutter Mobile Guide.

Production requirements

The quickstart procedure in this guide optimizes for getting you to a working app, not for production.

Before you deploy:

• If your app reads or writes through the Data API, review your Row Level Security policies. Any policy you added here is scoped to this quickstart's sample data, not to real user data.
• Set your Supabase credentials as environment variables on whatever platform you deploy to, rather than committing them to source control.
• Configure a custom domain for your Supabase project once you're ready to go live.

Android

In production, your Android app needs explicit permission to use the internet connection on the user's device which is required to communicate with Supabase APIs. To do this, add the following line to the android/app/src/main/AndroidManifest.xml file.

<manifest xmlns:android="http://schemas.android.com/apk/res/android">
  <!-- Required to fetch data from the internet. -->
  <uses-permission android:name="android.permission.INTERNET" />
  <!-- ... -->
</manifest>

Next steps

• Learn how to build a complete user management app with authentication in the Flutter tutorial
• Explore the supabase-flutter library on GitHub
• Insert more data into your database
• Upload and serve static files using Storage