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:

• Zuvo 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.
• Zuvo Auth - allow users to sign up and log in.
• Zuvo Storage - allow users to upload a profile photo.

Project setup

Before you start building you need to set up the Database and API. You can do this by starting a new Project in Zuvo and then creating a "schema" inside the database.

Create a project

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

Set up the database schema

Now set up the database schema. You can use the "User Management Starter" quickstart in the SQL Editor, or you can copy/paste the SQL from below and run it.

supabase migration new user_management_starter

Building the app

Build the Flutter app from scratch.

Initialize a Flutter app

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

flutter create supabase_quickstart

Then install the only additional dependency: supabase_flutter

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

supabase_flutter: ^2.0.0

Run flutter pub get to install the dependencies.

Setup deep links

With dependencies installed, set up 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 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.

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

import 'package:flutter_web_plugins/url_strategy.dart';

void main() {
  usePathUrlStrategy();
  runApp(ExampleApp());
}

Main function

With deep links configured, initialize the Zuvo client inside the 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.

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

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.

Set up account page

After a user is signed in we can allow them to edit their profile details and manage their account. Create a new widget called account_page.dart.

Launch!

With all components in place, 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.

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

flutter run

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

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.

Bonus: Profile photos

Every Zuvo 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:

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

Create an avatar so the user can upload a profile photo. We can start by creating a new component:

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.

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

See also

• Flutter Tutorial: building a Flutter chat app
• Flutter Tutorial - Part 2: Authentication and Authorization with RLS