Flutter SDK

The ThunderID Flutter SDK provides a single Dart package for integrating authentication into your iOS and Android Flutter applications:

• thunderid_flutter: Core authentication client, reactive state management, and drop-in Flutter widgets

The package targets Flutter 3.16+ and Dart 3.2+. All protocol operations (OAuth2/OIDC, PKCE, token validation, token refresh) are delegated to the native ThunderID iOS and Android SDKs via Flutter platform channels: no OAuth2/OIDC logic runs in Dart.

Try the Sample App

See the Try the Flutter Sample App guide to run the sample app and see the full authentication lifecycle end to end.

Installation

pubspec.yaml

dependencies:
  thunderid_flutter: ^0.1.0

flutter pub get

Getting Started

To get started quickly, follow the Flutter Quickstart Guide for step-by-step setup instructions.

Quick Example

import 'package:flutter/material.dart';
import 'package:thunderid_flutter/thunderid_flutter.dart';

void main() {
  runApp(
    ThunderIDProvider(
      config: ThunderIDConfig(
        baseUrl: 'https://localhost:8090',
        clientId: '<your-client-id>',
        scopes: const ['openid', 'profile', 'email'],
        afterSignInUrl: 'dev.thunderid.app://callback',
        afterSignOutUrl: 'dev.thunderid.app://logout',
        applicationId: '<your-application-id>',
      ),
      child: const MyApp(),
    ),
  );
}

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Builder(
        builder: (context) {
          final thunder = ThunderIDProvider.of(context);
          if (!thunder.initialized) return const CircularProgressIndicator();
          return thunder.isSignedIn
              ? HomeScreen()
              : AuthScreen();
        },
      ),
    );
  }
}

Features

Core Client

Method	Description
initialize(config)	Initialize the SDK with configuration
signIn(payload, request)	App-native sign-in via the Flow Execution API
signUp(payload, request)	App-native registration via the Flow Execution API
buildSignInUrl(options)	Build an OAuth 2.0 authorization URL for redirect-based sign-in
handleRedirectCallback(url)	Exchange an authorization code for tokens after redirect
getAccessToken()	Retrieve the current access token, refreshing automatically if needed
getUser()	Retrieve the authenticated user from the JWT or /oauth2/userinfo
getUserProfile()	Fetch the full user profile from /scim2/Me
updateUserProfile(payload)	Update the user's profile
signOut(options)	Revoke the refresh token and clear the session
exchangeToken(config)	Perform an OAuth 2.0 token exchange (STS)
decodeJwtToken(token)	Decode a JWT string into a Map<String, dynamic>

Widgets

Actions

Widget	Description
SignInButton(onTap)	Pre-styled button that triggers your sign-in flow
SignOutButton(onSignOutComplete)	Calls signOut() and refreshes auth state
SignUpButton(onTap)	Pre-styled button that triggers your registration flow

Presentation

Widget	Description
SignIn(applicationId, onComplete, onError)	Full embedded sign-in form driven by the Flow Execution API
BaseSignIn(applicationId, onComplete, onError, builder)	Builder variant; receives SignInState for custom form UI
SignUp(applicationId, onComplete, onError)	Full embedded registration form
BaseSignUp(applicationId, onComplete, onError, builder)	Builder variant for custom registration UI
UserProfile(onSaved, onError)	Editable profile form; loads from /scim2/Me and saves via updateUserProfile
BaseUserProfile(onSaved, onError, builder)	Builder variant with full control over the form layout

Guards

Widget	Description
SignedIn(child, fallback)	Renders child only when the user is authenticated
SignedOut(child, fallback)	Renders child only when the user is not authenticated

State

Type	Description
ThunderIDProvider	Root widget that injects ThunderIDState into the widget tree
ThunderIDProvider.of(context)	Access the current ThunderIDState from any widget

Architecture

Flutter (Dart)                    Native
┌─────────────────────┐          ┌──────────────────────┐
│ ThunderIDClient     │          │ ThunderID iOS SDK    │
│ ThunderIDProvider   │ ──────── │ (Swift, Keychain)    │
│ Widgets             │ channel  ├──────────────────────┤
└─────────────────────┘          │ ThunderID Android SDK│
                                 │ (Kotlin, Keystore)   │
                                 └──────────────────────┘

Customization

• Use SignIn and SignUp for pre-built forms, or BaseSignIn and BaseSignUp to render your own UI with the same Flow Execution loop
• Provide custom button UI while delegating auth logic to ThunderIDProvider.of(context).client
• Override localized strings via the preferences parameter on ThunderIDConfig