Getting Started

Build a User Management App with Flutter


This tutorial demonstrates how to build a basic user management app. The app authenticates and identifies the user, stores their profile information in the database, and allows the user to log in, update their profile details, and upload a profile photo. The app uses:

  • Supabase Database - a Postgres database for storing your user data and Row Level Security so data is protected and users can only access their own information.
  • Supabase Auth - users log in through magic links sent to their email (without having to set up passwords).
  • Supabase Storage - users can upload a profile photo.

Supabase User Management example

Project setup

Before we start building we're going to set up our Database and API. This is as simple as starting a new Project in Supabase and then creating a "schema" inside the database.

Create a project

  1. Create a new project in the Supabase Dashboard.
  2. Enter your project details.
  3. Wait for the new database to launch.

Set up the database schema

Now we are going to set up the database schema. We can use the "User Management Starter" quickstart in the SQL Editor, or you can just copy/paste the SQL from below and run it yourself.

  1. Go to the SQL Editor page in the Dashboard.
  2. Click User Management Starter.
  3. Click Run.

_10
supabase link --project-ref <project-id>
_10
# You can get <project-id> from your project's dashboard URL: https://supabase.com/dashboard/project/<project-id>
_10
supabase db pull

Get the API Keys

Now that you've created some database tables, you are ready to insert data using the auto-generated API. We just need to get the Project URL and anon key from the API settings.

  1. Go to the API Settings page in the Dashboard.
  2. Find your Project URL, anon, and service_role keys on this page.

Building the app

Let's start building the Flutter app from scratch.

Initialize a Flutter app

We can use flutter create to initialize an app called supabase_quickstart:


_10
flutter create supabase_quickstart

Then let's install the only additional dependency: supabase_flutter

Copy and paste the following line in your pubspec.yaml to install the package:


_10
supabase_flutter: ^2.0.0

Run flutter pub get to install the dependencies.

Now that we have the dependencies installed let's setup deep links. Setting up deep links is required to bring back the user to the app when they click on the magic link to sign in. We can setup deep links with just a minor tweak on our Flutter application.

We have to use io.supabase.flutterquickstart as the scheme. In this example, we will use login-callback as the host for our deep link, but you can change it to whatever you would like.

First, add io.supabase.flutterquickstart://login-callback/ as a new redirect URL in the Dashboard.

Supabase console deep link setting

That is it on Supabase's end and the rest are platform specific settings:

Edit the ios/Runner/Info.plist file.

Add CFBundleURLTypes to enable deep linking:

ios/Runner/Info.plist"

_20
<!-- ... other tags -->
_20
<plist>
_20
<dict>
_20
<!-- ... other tags -->
_20
_20
<!-- Add this array for Deep Links -->
_20
<key>CFBundleURLTypes</key>
_20
<array>
_20
<dict>
_20
<key>CFBundleTypeRole</key>
_20
<string>Editor</string>
_20
<key>CFBundleURLSchemes</key>
_20
<array>
_20
<string>io.supabase.flutterquickstart</string>
_20
</array>
_20
</dict>
_20
</array>
_20
<!-- ... other tags -->
_20
</dict>
_20
</plist>

Main function

Now that we have deep links ready let's initialize the Supabase client inside our main function with the API credentials that you copied earlier. These variables will be exposed on the app, and that's completely fine since we have Row Level Security enabled on our Database.

lib/main.dart

_34
import 'package:flutter/material.dart';
_34
import 'package:supabase_flutter/supabase_flutter.dart';
_34
_34
Future<void> main() async {
_34
await Supabase.initialize(
_34
url: 'YOUR_SUPABASE_URL',
_34
anonKey: 'YOUR_SUPABASE_ANON_KEY',
_34
);
_34
runApp(const MyApp());
_34
}
_34
_34
final supabase = Supabase.instance.client;
_34
_34
class MyApp extends StatelessWidget {
_34
const MyApp({super.key});
_34
_34
@override
_34
Widget build(BuildContext context) {
_34
return const MaterialApp(title: 'Supabase Flutter');
_34
}
_34
}
_34
_34
extension ContextExtension on BuildContext {
_34
void showSnackBar(String message, {bool isError = false}) {
_34
ScaffoldMessenger.of(this).showSnackBar(
_34
SnackBar(
_34
content: Text(message),
_34
backgroundColor: isError
_34
? Theme.of(this).colorScheme.error
_34
: Theme.of(this).snackBarTheme.backgroundColor,
_34
),
_34
);
_34
}
_34
}

Notice that we have a showSnackBar extension method that we will use to show snack bars in the app. You could define this method in a separate file and import it where needed, but for simplicity, we will define it here.

Set up a login page

Let's create a Flutter widget to manage logins and sign ups. We will use Magic Links, so users can sign in with their email without using passwords.

Notice that this page sets up a listener on the user's auth state using onAuthStateChange. A new event will fire when the user comes back to the app by clicking their magic link, which this page can catch and redirect the user accordingly.

lib/pages/login_page.dart

_105
import 'dart:async';
_105
_105
import 'package:flutter/foundation.dart';
_105
import 'package:flutter/material.dart';
_105
import 'package:supabase_flutter/supabase_flutter.dart';
_105
import 'package:supabase_quickstart/main.dart';
_105
import 'package:supabase_quickstart/pages/account_page.dart';
_105
_105
class LoginPage extends StatefulWidget {
_105
const LoginPage({super.key});
_105
_105
@override
_105
State<LoginPage> createState() => _LoginPageState();
_105
}
_105
_105
class _LoginPageState extends State<LoginPage> {
_105
bool _isLoading = false;
_105
bool _redirecting = false;
_105
late final TextEditingController _emailController = TextEditingController();
_105
late final StreamSubscription<AuthState> _authStateSubscription;
_105
_105
Future<void> _signIn() async {
_105
try {
_105
setState(() {
_105
_isLoading = true;
_105
});
_105
await supabase.auth.signInWithOtp(
_105
email: _emailController.text.trim(),
_105
emailRedirectTo:
_105
kIsWeb ? null : 'io.supabase.flutterquickstart://login-callback/',
_105
);
_105
if (mounted) {
_105
context.showSnackBar('Check your email for a login link!');
_105
_105
_emailController.clear();
_105
}
_105
} on AuthException catch (error) {
_105
if (mounted) context.showSnackBar(error.message, isError: true);
_105
} catch (error) {
_105
if (mounted) {
_105
context.showSnackBar('Unexpected error occurred', isError: true);
_105
}
_105
} finally {
_105
if (mounted) {
_105
setState(() {
_105
_isLoading = false;
_105
});
_105
}
_105
}
_105
}
_105
_105
@override
_105
void initState() {
_105
_authStateSubscription = supabase.auth.onAuthStateChange.listen(
_105
(data) {
_105
if (_redirecting) return;
_105
final session = data.session;
_105
if (session != null) {
_105
_redirecting = true;
_105
Navigator.of(context).pushReplacement(
_105
MaterialPageRoute(builder: (context) => const AccountPage()),
_105
);
_105
}
_105
},
_105
onError: (error) {
_105
if (error is AuthException) {
_105
context.showSnackBar(error.message, isError: true);
_105
} else {
_105
context.showSnackBar('Unexpected error occurred', isError: true);
_105
}
_105
},
_105
);
_105
super.initState();
_105
}
_105
_105
@override
_105
void dispose() {
_105
_emailController.dispose();
_105
_authStateSubscription.cancel();
_105
super.dispose();
_105
}
_105
_105
@override
_105
Widget build(BuildContext context) {
_105
return Scaffold(
_105
appBar: AppBar(title: const Text('Sign In')),
_105
body: ListView(
_105
padding: const EdgeInsets.symmetric(vertical: 18, horizontal: 12),
_105
children: [
_105
const Text('Sign in via the magic link with your email below'),
_105
const SizedBox(height: 18),
_105
TextFormField(
_105
controller: _emailController,
_105
decoration: const InputDecoration(labelText: 'Email'),
_105
),
_105
const SizedBox(height: 18),
_105
ElevatedButton(
_105
onPressed: _isLoading ? null : _signIn,
_105
child: Text(_isLoading ? 'Sending...' : 'Send Magic Link'),
_105
),
_105
],
_105
),
_105
);
_105
}
_105
}

Set up account page

After a user is signed in we can allow them to edit their profile details and manage their account. Let's create a new widget called account_page.dart for that.

lib/pages/account_page.dart"

_138
import 'package:flutter/material.dart';
_138
import 'package:supabase_flutter/supabase_flutter.dart';
_138
import 'package:supabase_quickstart/main.dart';
_138
import 'package:supabase_quickstart/pages/login_page.dart';
_138
_138
class AccountPage extends StatefulWidget {
_138
const AccountPage({super.key});
_138
_138
@override
_138
State<AccountPage> createState() => _AccountPageState();
_138
}
_138
_138
class _AccountPageState extends State<AccountPage> {
_138
final _usernameController = TextEditingController();
_138
final _websiteController = TextEditingController();
_138
_138
String? _avatarUrl;
_138
var _loading = true;
_138
_138
/// Called once a user id is received within `onAuthenticated()`
_138
Future<void> _getProfile() async {
_138
setState(() {
_138
_loading = true;
_138
});
_138
_138
try {
_138
final userId = supabase.auth.currentSession!.user.id;
_138
final data =
_138
await supabase.from('profiles').select().eq('id', userId).single();
_138
_usernameController.text = (data['username'] ?? '') as String;
_138
_websiteController.text = (data['website'] ?? '') as String;
_138
_avatarUrl = (data['avatar_url'] ?? '') as String;
_138
} on PostgrestException catch (error) {
_138
if (mounted) context.showSnackBar(error.message, isError: true);
_138
} catch (error) {
_138
if (mounted) {
_138
context.showSnackBar('Unexpected error occurred', isError: true);
_138
}
_138
} finally {
_138
if (mounted) {
_138
setState(() {
_138
_loading = false;
_138
});
_138
}
_138
}
_138
}
_138
_138
/// Called when user taps `Update` button
_138
Future<void> _updateProfile() async {
_138
setState(() {
_138
_loading = true;
_138
});
_138
final userName = _usernameController.text.trim();
_138
final website = _websiteController.text.trim();
_138
final user = supabase.auth.currentUser;
_138
final updates = {
_138
'id': user!.id,
_138
'username': userName,
_138
'website': website,
_138
'updated_at': DateTime.now().toIso8601String(),
_138
};
_138
try {
_138
await supabase.from('profiles').upsert(updates);
_138
if (mounted) context.showSnackBar('Successfully updated profile!');
_138
} on PostgrestException catch (error) {
_138
if (mounted) context.showSnackBar(error.message, isError: true);
_138
} catch (error) {
_138
if (mounted) {
_138
context.showSnackBar('Unexpected error occurred', isError: true);
_138
}
_138
} finally {
_138
if (mounted) {
_138
setState(() {
_138
_loading = false;
_138
});
_138
}
_138
}
_138
}
_138
_138
Future<void> _signOut() async {
_138
try {
_138
await supabase.auth.signOut();
_138
} on AuthException catch (error) {
_138
if (mounted) context.showSnackBar(error.message, isError: true);
_138
} catch (error) {
_138
if (mounted) {
_138
context.showSnackBar('Unexpected error occurred', isError: true);
_138
}
_138
} finally {
_138
if (mounted) {
_138
Navigator.of(context).pushReplacement(
_138
MaterialPageRoute(builder: (_) => const LoginPage()),
_138
);
_138
}
_138
}
_138
}
_138
_138
@override
_138
void initState() {
_138
super.initState();
_138
_getProfile();
_138
}
_138
_138
@override
_138
void dispose() {
_138
_usernameController.dispose();
_138
_websiteController.dispose();
_138
super.dispose();
_138
}
_138
_138
@override
_138
Widget build(BuildContext context) {
_138
return Scaffold(
_138
appBar: AppBar(title: const Text('Profile')),
_138
body: ListView(
_138
padding: const EdgeInsets.symmetric(vertical: 18, horizontal: 12),
_138
children: [
_138
TextFormField(
_138
controller: _usernameController,
_138
decoration: const InputDecoration(labelText: 'User Name'),
_138
),
_138
const SizedBox(height: 18),
_138
TextFormField(
_138
controller: _websiteController,
_138
decoration: const InputDecoration(labelText: 'Website'),
_138
),
_138
const SizedBox(height: 18),
_138
ElevatedButton(
_138
onPressed: _loading ? null : _updateProfile,
_138
child: Text(_loading ? 'Saving...' : 'Update'),
_138
),
_138
const SizedBox(height: 18),
_138
TextButton(onPressed: _signOut, child: const Text('Sign Out')),
_138
],
_138
),
_138
);
_138
}
_138
}

Launch!

Now that we have all the components in place, let's update lib/main.dart. The home of the MaterialApp, meaning the initial page shown to the user, will be the LoginPage if the user is not authenticated, and the AccountPage if the user is authenticated. We also included some theming to make the app look a bit nicer.

lib/main.dart

_55
import 'package:flutter/material.dart';
_55
import 'package:supabase_flutter/supabase_flutter.dart';
_55
import 'package:supabase_quickstart/pages/account_page.dart';
_55
import 'package:supabase_quickstart/pages/login_page.dart';
_55
_55
Future<void> main() async {
_55
await Supabase.initialize(
_55
url: 'YOUR_SUPABASE_URL',
_55
anonKey: 'YOUR_SUPABASE_ANON_KEY',
_55
);
_55
runApp(const MyApp());
_55
}
_55
_55
final supabase = Supabase.instance.client;
_55
_55
class MyApp extends StatelessWidget {
_55
const MyApp({super.key});
_55
_55
@override
_55
Widget build(BuildContext context) {
_55
return MaterialApp(
_55
title: 'Supabase Flutter',
_55
theme: ThemeData.dark().copyWith(
_55
primaryColor: Colors.green,
_55
textButtonTheme: TextButtonThemeData(
_55
style: TextButton.styleFrom(
_55
foregroundColor: Colors.green,
_55
),
_55
),
_55
elevatedButtonTheme: ElevatedButtonThemeData(
_55
style: ElevatedButton.styleFrom(
_55
foregroundColor: Colors.white,
_55
backgroundColor: Colors.green,
_55
),
_55
),
_55
),
_55
home: supabase.auth.currentSession == null
_55
? const LoginPage()
_55
: const AccountPage(),
_55
);
_55
}
_55
}
_55
_55
extension ContextExtension on BuildContext {
_55
void showSnackBar(String message, {bool isError = false}) {
_55
ScaffoldMessenger.of(this).showSnackBar(
_55
SnackBar(
_55
content: Text(message),
_55
backgroundColor: isError
_55
? Theme.of(this).colorScheme.error
_55
: Theme.of(this).snackBarTheme.backgroundColor,
_55
),
_55
);
_55
}
_55
}

Once that's done, run this in a terminal window to launch on Android or iOS:


_10
flutter run

Or for web, run the following command to launch it on localhost:3000


_10
flutter run -d web-server --web-hostname localhost --web-port 3000

And then open the browser to localhost:3000 and you should see the completed app.

Supabase User Management example

Bonus: Profile photos

Every Supabase project is configured with Storage for managing large files like photos and videos.

Making sure we have a public bucket

We will be storing the image as a publicly sharable image. Make sure your avatars bucket is set to public, and if it is not, change the publicity by clicking the dot menu that appears when you hover over the bucket name. You should see an orange Public badge next to your bucket name if your bucket is set to public.

Adding image uploading feature to account page

We will use image_picker plugin to select an image from the device.

Add the following line in your pubspec.yaml file to install image_picker:


_10
image_picker: ^1.0.5

Using image_picker requires some additional preparation depending on the platform. Follow the instruction on README.md of image_picker on how to set it up for the platform you are using.

Once you are done with all of the above, it is time to dive into coding.

Create an upload widget

Let's create an avatar for the user so that they can upload a profile photo. We can start by creating a new component:

lib/components/avatar.dart

_89
import 'package:flutter/material.dart';
_89
import 'package:image_picker/image_picker.dart';
_89
import 'package:supabase_flutter/supabase_flutter.dart';
_89
import 'package:supabase_quickstart/main.dart';
_89
_89
class Avatar extends StatefulWidget {
_89
const Avatar({
_89
super.key,
_89
required this.imageUrl,
_89
required this.onUpload,
_89
});
_89
_89
final String? imageUrl;
_89
final void Function(String) onUpload;
_89
_89
@override
_89
State<Avatar> createState() => _AvatarState();
_89
}
_89
_89
class _AvatarState extends State<Avatar> {
_89
bool _isLoading = false;
_89
_89
@override
_89
Widget build(BuildContext context) {
_89
return Column(
_89
children: [
_89
if (widget.imageUrl == null || widget.imageUrl!.isEmpty)
_89
Container(
_89
width: 150,
_89
height: 150,
_89
color: Colors.grey,
_89
child: const Center(
_89
child: Text('No Image'),
_89
),
_89
)
_89
else
_89
Image.network(
_89
widget.imageUrl!,
_89
width: 150,
_89
height: 150,
_89
fit: BoxFit.cover,
_89
),
_89
ElevatedButton(
_89
onPressed: _isLoading ? null : _upload,
_89
child: const Text('Upload'),
_89
),
_89
],
_89
);
_89
}
_89
_89
Future<void> _upload() async {
_89
final picker = ImagePicker();
_89
final imageFile = await picker.pickImage(
_89
source: ImageSource.gallery,
_89
maxWidth: 300,
_89
maxHeight: 300,
_89
);
_89
if (imageFile == null) {
_89
return;
_89
}
_89
setState(() => _isLoading = true);
_89
_89
try {
_89
final bytes = await imageFile.readAsBytes();
_89
final fileExt = imageFile.path.split('.').last;
_89
final fileName = '${DateTime.now().toIso8601String()}.$fileExt';
_89
final filePath = fileName;
_89
await supabase.storage.from('avatars').uploadBinary(
_89
filePath,
_89
bytes,
_89
fileOptions: FileOptions(contentType: imageFile.mimeType),
_89
);
_89
final imageUrlResponse = await supabase.storage
_89
.from('avatars')
_89
.createSignedUrl(filePath, 60 * 60 * 24 * 365 * 10);
_89
widget.onUpload(imageUrlResponse);
_89
} on StorageException catch (error) {
_89
if (mounted) {
_89
context.showSnackBar(error.message, isError: true);
_89
}
_89
} catch (error) {
_89
if (mounted) {
_89
context.showSnackBar('Unexpected error occurred', isError: true);
_89
}
_89
}
_89
_89
setState(() => _isLoading = false);
_89
}
_89
}

Add the new widget

And then we can add the widget to the Account page as well as some logic to update the avatar_url whenever the user uploads a new avatar.

lib/pages/account_page.dart

_138
import 'package:flutter/material.dart';
_138
import 'package:supabase_flutter/supabase_flutter.dart';
_138
import 'package:supabase_quickstart/main.dart';
_138
import 'package:supabase_quickstart/pages/login_page.dart';
_138
_138
class AccountPage extends StatefulWidget {
_138
const AccountPage({super.key});
_138
_138
@override
_138
State<AccountPage> createState() => _AccountPageState();
_138
}
_138
_138
class _AccountPageState extends State<AccountPage> {
_138
final _usernameController = TextEditingController();
_138
final _websiteController = TextEditingController();
_138
_138
String? _avatarUrl;
_138
var _loading = true;
_138
_138
/// Called once a user id is received within `onAuthenticated()`
_138
Future<void> _getProfile() async {
_138
setState(() {
_138
_loading = true;
_138
});
_138
_138
try {
_138
final userId = supabase.auth.currentSession!.user.id;
_138
final data =
_138
await supabase.from('profiles').select().eq('id', userId).single();
_138
_usernameController.text = (data['username'] ?? '') as String;
_138
_websiteController.text = (data['website'] ?? '') as String;
_138
_avatarUrl = (data['avatar_url'] ?? '') as String;
_138
} on PostgrestException catch (error) {
_138
if (mounted) context.showSnackBar(error.message, isError: true);
_138
} catch (error) {
_138
if (mounted) {
_138
context.showSnackBar('Unexpected error occurred', isError: true);
_138
}
_138
} finally {
_138
if (mounted) {
_138
setState(() {
_138
_loading = false;
_138
});
_138
}
_138
}
_138
}
_138
_138
/// Called when user taps `Update` button
_138
Future<void> _updateProfile() async {
_138
setState(() {
_138
_loading = true;
_138
});
_138
final userName = _usernameController.text.trim();
_138
final website = _websiteController.text.trim();
_138
final user = supabase.auth.currentUser;
_138
final updates = {
_138
'id': user!.id,
_138
'username': userName,
_138
'website': website,
_138
'updated_at': DateTime.now().toIso8601String(),
_138
};
_138
try {
_138
await supabase.from('profiles').upsert(updates);
_138
if (mounted) context.showSnackBar('Successfully updated profile!');
_138
} on PostgrestException catch (error) {
_138
if (mounted) context.showSnackBar(error.message, isError: true);
_138
} catch (error) {
_138
if (mounted) {
_138
context.showSnackBar('Unexpected error occurred', isError: true);
_138
}
_138
} finally {
_138
if (mounted) {
_138
setState(() {
_138
_loading = false;
_138
});
_138
}
_138
}
_138
}
_138
_138
Future<void> _signOut() async {
_138
try {
_138
await supabase.auth.signOut();
_138
} on AuthException catch (error) {
_138
if (mounted) context.showSnackBar(error.message, isError: true);
_138
} catch (error) {
_138
if (mounted) {
_138
context.showSnackBar('Unexpected error occurred', isError: true);
_138
}
_138
} finally {
_138
if (mounted) {
_138
Navigator.of(context).pushReplacement(
_138
MaterialPageRoute(builder: (_) => const LoginPage()),
_138
);
_138
}
_138
}
_138
}
_138
_138
@override
_138
void initState() {
_138
super.initState();
_138
_getProfile();
_138
}
_138
_138
@override
_138
void dispose() {
_138
_usernameController.dispose();
_138
_websiteController.dispose();
_138
super.dispose();
_138
}
_138
_138
@override
_138
Widget build(BuildContext context) {
_138
return Scaffold(
_138
appBar: AppBar(title: const Text('Profile')),
_138
body: ListView(
_138
padding: const EdgeInsets.symmetric(vertical: 18, horizontal: 12),
_138
children: [
_138
TextFormField(
_138
controller: _usernameController,
_138
decoration: const InputDecoration(labelText: 'User Name'),
_138
),
_138
const SizedBox(height: 18),
_138
TextFormField(
_138
controller: _websiteController,
_138
decoration: const InputDecoration(labelText: 'Website'),
_138
),
_138
const SizedBox(height: 18),
_138
ElevatedButton(
_138
onPressed: _loading ? null : _updateProfile,
_138
child: Text(_loading ? 'Saving...' : 'Update'),
_138
),
_138
const SizedBox(height: 18),
_138
TextButton(onPressed: _signOut, child: const Text('Sign Out')),
_138
],
_138
),
_138
);
_138
}
_138
}

Congratulations, you've built a fully functional user management app using Flutter and Supabase!

See also