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aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-4"><li class="nav-item"><a class="nav-link" href="/release/upgrade"><div><span>Upgrade</span></div></a></li><li class="nav-item"><a class="nav-link" href="/release/archive"><div><span>SDK archive</span></div></a></li><div class="sidenav-divider"></div><li class="nav-item"><a class="nav-link" href="/release/whats-new"><div><span>What's new</span></div></a></li><li class="nav-item"><a class="nav-link" href="/release/release-notes"><div><span>Release notes</span></div></a></li><li class="nav-item"><a class="nav-link" href="/release/breaking-changes"><div><span>Breaking changes</span></div></a></li><li class="nav-item"><a class="nav-link" href="/release/compatibility-policy"><div><span>Compatibility policy</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-5" role="button" aria-expanded="false" aria-controls="sidenav-5"><span>App solutions</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5"><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-1" role="button" aria-expanded="false" aria-controls="sidenav-5-1"><span>AI</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-1"><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-1-1" role="button" aria-expanded="false" aria-controls="sidenav-5-1-1"><span>AI Toolkit guide</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-1-1"><li class="nav-item"><a class="nav-link" href="/ai-toolkit"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ai-toolkit/user-experience"><div><span>User experience</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ai-toolkit/feature-integration"><div><span>Feature integration</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ai-toolkit/custom-llm-providers"><div><span>Custom LLM providers</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ai-toolkit/chat-client-sample"><div><span>Chat client sample</span></div></a></li></ul></li><li class="nav-item"><a class="nav-link" href="https://www.youtube.com/watch?v=1AuzJEiHjO4" target="_blank" rel="noopener"><div><span>Build with Google AI Dart SDK (video)</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-2" role="button" aria-expanded="false" aria-controls="sidenav-5-2"><span>Firebase & Firestore</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-2"><li class="nav-item"><a class="nav-link" href="/data-and-backend/firebase"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://firebase.google.com/docs/flutter" target="_blank" rel="noopener"><div><span>Discover Firebase for Flutter</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://www.youtube.com/watch?v=wUSkeTaBonA" target="_blank" rel="noopener"><div><span>Get to know Firebase for Flutter</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://firebase.google.com/codelabs/firebase-auth-in-flutter-apps" target="_blank" rel="noopener"><div><span>Add a user authentication flow to a Flutter app using FirebaseUI</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://firebase.google.com/codelabs/firebase-get-to-know-web" target="_blank" rel="noopener"><div><span>Get to know Firebase for web</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-3" role="button" aria-expanded="false" aria-controls="sidenav-5-3"><span>Games</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-3"><li class="nav-item"><a class="nav-link" href="/resources/games-toolkit"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/games/achievements-leaderboard"><div><span>Add achievements and leaderboards</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://firebase.google.com/codelabs/build-leaderboards-with-firestore#0" target="_blank" rel="noopener"><div><span>Build leaderboards with Firestore</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/plugins/google-mobile-ads"><div><span>Add advertising</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/games/firestore-multiplayer"><div><span>Add multiplayer support</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://codelabs.developers.google.com/codelabs/flutter-in-app-purchases" target="_blank" rel="noopener"><div><span>Add in-app purchases</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://firebase.google.com/codelabs/firebase-auth-in-flutter-apps" target="_blank" rel="noopener"><div><span>Add user authentication</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://firebase.google.com/docs/crashlytics/get-started?platform=flutter" target="_blank" rel="noopener"><div><span>Debug using Crashlytics</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://codelabs.developers.google.com/codelabs/flutter-flame-brick-breaker" target="_blank" rel="noopener"><div><span>Intro to Flame with Flutter</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-4" role="button" aria-expanded="false" aria-controls="sidenav-5-4"><span>Monetization</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-4"><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-4-1" role="button" aria-expanded="false" aria-controls="sidenav-5-4-1"><span>Advertising</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-4-1"><li class="nav-item"><a class="nav-link" href="/resources/ads-overview"><div><span>Ads overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/plugins/google-mobile-ads"><div><span>Add advertising</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://codelabs.developers.google.com/codelabs/admob-ads-in-flutter" target="_blank" rel="noopener"><div><span>Add AdMob ads to your Flutter app</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://codelabs.developers.google.com/codelabs/admob-inline-ads-in-flutter" target="_blank" rel="noopener"><div><span>Add an AdMob banner and native inline ads</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://developers.google.com/admob/flutter/mediation" target="_blank" rel="noopener"><div><span>Google AdMob mediation</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://pub.dev/packages/interactive_media_ads" target="_blank" rel="noopener"><div><span>Interactive Media Ads SDK</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-4-2" role="button" aria-expanded="false" aria-controls="sidenav-5-4-2"><span>In-app purchases</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-4-2"><li class="nav-item"><a class="nav-link" href="/resources/in-app-purchases-overview"><div><span>In-app purchases overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://codelabs.developers.google.com/codelabs/flutter-in-app-purchases" target="_blank" rel="noopener"><div><span>Add in-app purchases</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-4-3" role="button" aria-expanded="false" aria-controls="sidenav-5-4-3"><span>Payments</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-4-3"><li class="nav-item"><a class="nav-link" href="/resources/payments-overview"><div><span>Payments overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://pub.dev/packages/pay" target="_blank" rel="noopener"><div><span>Google pay package</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-5" role="button" aria-expanded="false" aria-controls="sidenav-5-5"><span>Maps</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-5"><li class="nav-item"><a class="nav-link" href="https://codelabs.developers.google.com/codelabs/google-maps-in-flutter" target="_blank" rel="noopener"><div><span>Add Google maps to a Flutter app</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://developers.google.com/maps/flutter-package" target="_blank" rel="noopener"><div><span>Google Maps package</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-5-6" role="button" aria-expanded="false" aria-controls="sidenav-5-6"><span>News</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-5-6"><li class="nav-item"><a class="nav-link" href="/resources/news-toolkit"><div><span>Build a news app</span></div></a></li></ul></li></ul></li><li aria-hidden="true"><div class="sidenav-divider"></div></li><li class="nav-header">User interface</li><li class="nav-item"><a class="nav-link" href="/ui"><div><span>Introduction</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/widgets"><div><span>Widget catalog</span></div></a></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-10" role="button" aria-expanded="false" aria-controls="sidenav-10"><span>Layout</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-10"><li class="nav-item"><a class="nav-link" href="/ui/layout"><div><span>Introduction</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/layout/tutorial"><div><span>Build a layout</span></div></a></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-10-3" role="button" aria-expanded="false" aria-controls="sidenav-10-3"><span>Lists & grids</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-10-3"><li class="nav-item"><a class="nav-link" href="/cookbook/lists/basic-list"><div><span>Create and use lists</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/lists/horizontal-list"><div><span>Create a horizontal list</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/lists/grid-lists"><div><span>Create a grid view</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/lists/mixed-list"><div><span>Create lists with different types of items</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/lists/spaced-items"><div><span>Create lists with spaced items</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/lists/long-lists"><div><span>Work with long lists</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-10-4" role="button" aria-expanded="false" aria-controls="sidenav-10-4"><span>Scrolling</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-10-4"><li class="nav-item"><a class="nav-link" href="/ui/layout/scrolling"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/layout/scrolling/slivers"><div><span>Use slivers to achieve fancy scrolling</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/lists/floating-app-bar"><div><span>Place a floating app bar above a list</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/effects/parallax-scrolling"><div><span>Create a scrolling parallax effect</span></div></a></li></ul></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-11" role="button" aria-expanded="false" aria-controls="sidenav-11"><span>Adaptive & responsive design</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-11"><li class="nav-item"><a class="nav-link" href="/ui/adaptive-responsive"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/adaptive-responsive/general"><div><span>General approach</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/adaptive-responsive/safearea-mediaquery"><div><span>SafeArea & MediaQuery</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/adaptive-responsive/large-screens"><div><span>Large screens & foldables</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/adaptive-responsive/input"><div><span>User input & accessibility</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/adaptive-responsive/capabilities"><div><span>Capabilities & policies</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/adaptive-responsive/platform-adaptations"><div><span>Automatic platform adaptations</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/adaptive-responsive/best-practices"><div><span>Best practices</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/adaptive-responsive/more-info"><div><span>Additional resources</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-12" role="button" aria-expanded="false" aria-controls="sidenav-12"><span>Design & theming</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-12"><li class="nav-item"><a class="nav-link" href="/cookbook/design/themes"><div><span>Share styles with themes</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/design/material"><div><span>Material design</span></div></a></li><li class="nav-item"><a class="nav-link" href="/release/breaking-changes/material-3-migration"><div><span>Migrate to Material 3</span></div></a></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-12-4" role="button" aria-expanded="false" aria-controls="sidenav-12-4"><span>Text</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-12-4"><li class="nav-item"><a class="nav-link" href="/ui/design/text/typography"><div><span>Fonts & typography</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/design/fonts"><div><span>Use a custom font</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/design/package-fonts"><div><span>Export fonts from a package</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://pub.dev/packages/google_fonts" target="_blank" rel="noopener"><div><span>Google Fonts package</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-12-5" role="button" aria-expanded="false" aria-controls="sidenav-12-5"><span>Custom graphics</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-12-5"><li class="nav-item"><a class="nav-link" href="/ui/design/graphics/fragment-shaders"><div><span>Use custom fragment shaders</span></div></a></li></ul></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-13" role="button" aria-expanded="false" aria-controls="sidenav-13"><span>Interactivity</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-13"><li class="nav-item"><a class="nav-link" href="/ui/interactivity"><div><span>Add interactivity to your app</span></div></a></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-13-2" role="button" aria-expanded="false" aria-controls="sidenav-13-2"><span>Gestures</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-13-2"><li class="nav-item"><a class="nav-link" href="/ui/interactivity/gestures"><div><span>Introduction</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/gestures/handling-taps"><div><span>Handle taps</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/interactivity/gestures/drag-outside"><div><span>Drag an object outside an app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/effects/drag-a-widget"><div><span>Drag a UI element within an app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/gestures/ripples"><div><span>Add Material touch ripples</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/gestures/dismissible"><div><span>Implement swipe to dismiss</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-13-3" role="button" aria-expanded="false" aria-controls="sidenav-13-3"><span>Input & forms</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-13-3"><li class="nav-item"><a class="nav-link" href="/cookbook/forms/text-input"><div><span>Create and style a text field</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/forms/retrieve-input"><div><span>Retrieve the value of a text field</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/forms/text-field-changes"><div><span>Handle changes to a text field</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/forms/focus"><div><span>Manage focus in text fields</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/forms/validation"><div><span>Build a form with validation</span></div></a></li></ul></li><li class="nav-item"><a class="nav-link" href="/cookbook/design/snackbars"><div><span>Display a snackbar</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/interactivity/actions-and-shortcuts"><div><span>Implement actions & shortcuts</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/interactivity/focus"><div><span>Manage keyboard focus</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-14" role="button" aria-expanded="false" aria-controls="sidenav-14"><span>Assets & media</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-14"><li class="nav-item"><a class="nav-link" href="/ui/assets/assets-and-images"><div><span>Add assets and images</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/images/network-image"><div><span>Display images from the internet</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/images/fading-in-images"><div><span>Fade in images with a placeholder</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/plugins/play-video"><div><span>Play and pause a video</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/assets/asset-transformation"><div><span>Transform assets at build time</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-15" role="button" aria-expanded="false" aria-controls="sidenav-15"><span>Navigation & routing</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-15"><li class="nav-item"><a class="nav-link" href="/ui/navigation"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/design/tabs"><div><span>Add tabs to your app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/navigation/navigation-basics"><div><span>Navigate to a new screen and back</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/navigation/passing-data"><div><span>Send data to a new screen</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/navigation/returning-data"><div><span>Return data from a screen</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/design/drawer"><div><span>Add a drawer to a screen</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/navigation/deep-linking"><div><span>Set up deep linking</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/navigation/set-up-app-links"><div><span>Set up app links for Android</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/navigation/set-up-universal-links"><div><span>Set up universal links for iOS</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/navigation/url-strategies"><div><span>Configure web URL strategies</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-16" role="button" aria-expanded="false" aria-controls="sidenav-16"><span>Animations & transitions</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-16"><li class="nav-item"><a class="nav-link" href="/ui/animations"><div><span>Introduction</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/animations/tutorial"><div><span>Tutorial</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/animations/implicit-animations"><div><span>Implicit animations</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/animation/animated-container"><div><span>Animate the properties of a container</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/animation/opacity-animation"><div><span>Fade a widget in and out</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/animations/hero-animations"><div><span>Hero animations</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/animation/page-route-animation"><div><span>Animate a page route transition</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/animation/physics-simulation"><div><span>Animate using a physics simulation</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/animations/staggered-animations"><div><span>Staggered animations</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/effects/staggered-menu-animation"><div><span>Create a staggered menu animation</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/animations/overview"><div><span>API overview</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-17" role="button" aria-expanded="false" aria-controls="sidenav-17"><span>Accessibility & internationalization</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-17"><li class="nav-item"><a class="nav-link" href="/ui/accessibility-and-internationalization/accessibility"><div><span>Accessibility</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/accessibility-and-internationalization/internationalization"><div><span>Internationalization</span></div></a></li></ul></li><li aria-hidden="true"><div class="sidenav-divider"></div></li><li class="nav-header">Beyond UI</li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-20" role="button" aria-expanded="false" aria-controls="sidenav-20"><span>Data & backend</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-20"><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-20-1" role="button" aria-expanded="false" aria-controls="sidenav-20-1"><span>State management</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-20-1"><li class="nav-item"><a class="nav-link" href="/data-and-backend/state-mgmt/intro"><div><span>Introduction</span></div></a></li><li class="nav-item"><a class="nav-link" href="/data-and-backend/state-mgmt/declarative"><div><span>Think declaratively</span></div></a></li><li class="nav-item"><a class="nav-link" href="/data-and-backend/state-mgmt/ephemeral-vs-app"><div><span>Ephemeral vs app state</span></div></a></li><li class="nav-item"><a class="nav-link" href="/data-and-backend/state-mgmt/simple"><div><span>Simple app state management</span></div></a></li><li class="nav-item"><a class="nav-link" href="/data-and-backend/state-mgmt/options"><div><span>Options</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-20-2" role="button" aria-expanded="false" aria-controls="sidenav-20-2"><span>Networking & http</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-20-2"><li class="nav-item"><a class="nav-link" href="/data-and-backend/networking"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/networking/fetch-data"><div><span>Fetch data from the internet</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/networking/authenticated-requests"><div><span>Make authenticated requests</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/networking/send-data"><div><span>Send data to the internet</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/networking/update-data"><div><span>Update data over the internet</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/networking/delete-data"><div><span>Delete data on the internet</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/networking/web-sockets"><div><span>Communicate with WebSockets</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-20-3" role="button" aria-expanded="false" aria-controls="sidenav-20-3"><span>Serialization</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-20-3"><li class="nav-item"><a class="nav-link" href="/data-and-backend/serialization/json"><div><span>JSON serialization</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/networking/background-parsing"><div><span>Parse JSON in the background</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-20-4" role="button" aria-expanded="false" aria-controls="sidenav-20-4"><span>Persistence</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-20-4"><li class="nav-item"><a class="nav-link" href="/cookbook/persistence/key-value"><div><span>Store key-value data on disk</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/persistence/reading-writing-files"><div><span>Read and write files</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/persistence/sqlite"><div><span>Persist data with SQLite</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-20-5" role="button" aria-expanded="false" aria-controls="sidenav-20-5"><span>Firebase</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-20-5"><li class="nav-item"><a class="nav-link" href="/data-and-backend/firebase"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://firebase.google.com/docs/flutter/setup" target="_blank" rel="noopener"><div><span>Add Firebase to your Flutter app</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li><li class="nav-item"><a class="nav-link" href="/data-and-backend/google-apis"><div><span>Google APIs</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link active collapsible" data-toggle="collapse" data-target="#sidenav-21" role="button" aria-expanded="true" aria-controls="sidenav-21"><span>App architecture</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse show" id="sidenav-21"><li class="nav-item"><a class="nav-link" href="/app-architecture"><div><span>Introduction</span></div></a></li><li class="nav-item"><a class="nav-link" href="/app-architecture/concepts"><div><span>Architecture concepts</span></div></a></li><li class="nav-item"><a class="nav-link active" href="/app-architecture/guide"><div><span>Guide to app architecture</span></div></a></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-21-4" role="button" aria-expanded="false" aria-controls="sidenav-21-4"><span>Architecture case study</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-21-4"><li class="nav-item"><a class="nav-link" href="/app-architecture/case-study"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/app-architecture/case-study/ui-layer"><div><span>UI layer</span></div></a></li><li class="nav-item"><a class="nav-link" href="/app-architecture/case-study/data-layer"><div><span>Data layer</span></div></a></li><li class="nav-item"><a class="nav-link" href="/app-architecture/case-study/dependency-injection"><div><span>Dependency injection</span></div></a></li><li class="nav-item"><a class="nav-link" href="/app-architecture/case-study/testing"><div><span>Testing each layer</span></div></a></li></ul></li><li class="nav-item"><a class="nav-link" href="/app-architecture/recommendations"><div><span>Recommendations</span></div></a></li><li class="nav-item"><a class="nav-link" href="/app-architecture/design-patterns"><div><span>Design patterns</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-22" role="button" aria-expanded="false" aria-controls="sidenav-22"><span>Platform integration</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-22"><li class="nav-item"><a class="nav-link" href="/reference/supported-platforms"><div><span>Supported platforms</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/desktop"><div><span>Build desktop apps with Flutter</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/platform-channels"><div><span>Write platform-specific code</span></div></a></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-22-4" role="button" aria-expanded="false" aria-controls="sidenav-22-4"><span>Android</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-22-4"><li class="nav-item"><a class="nav-link" href="/platform-integration/android/install-android"><div><span>Add Android as build target</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/android/splash-screen"><div><span>Add a splash screen</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/android/predictive-back"><div><span>Add predictive back</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/android/c-interop"><div><span>Bind to native code</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/android/platform-views"><div><span>Host a native Android view</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/android/call-jetpack-apis"><div><span>Calling JetPack APIs</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/android/compose-activity"><div><span>Launch a Jetpack Compose activity</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/android/restore-state-android"><div><span>Restore state on Android</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/android/chromeos"><div><span>Target ChromeOS with Android</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-22-5" role="button" aria-expanded="false" aria-controls="sidenav-22-5"><span>iOS</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-22-5"><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/install-ios"><div><span>Add iOS as build target</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/ios-latest"><div><span>Flutter on latest iOS</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/apple-frameworks"><div><span>Leverage Apple's system libraries</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/launch-screen"><div><span>Add a launch screen</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/ios-app-clip"><div><span>Add iOS App Clip support</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/app-extensions"><div><span>Add iOS app extensions</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/c-interop"><div><span>Bind to native code</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/platform-views"><div><span>Host a native iOS view</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/ios-debugging"><div><span>Enable debugging on iOS</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/ios/restore-state-ios"><div><span>Restore state on iOS</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-22-6" role="button" aria-expanded="false" aria-controls="sidenav-22-6"><span>Linux</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-22-6"><li class="nav-item"><a class="nav-link" href="/platform-integration/linux/install-linux"><div><span>Add Linux as build target</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/linux/building"><div><span>Build a Linux app</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-22-7" role="button" aria-expanded="false" aria-controls="sidenav-22-7"><span>macOS</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-22-7"><li class="nav-item"><a class="nav-link" href="/platform-integration/macos/install-macos"><div><span>Add macOS as build target</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/macos/building"><div><span>Build a macOS app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/macos/c-interop"><div><span>Bind to native code</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/macos/platform-views"><div><span>Host a native macOS view</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-22-8" role="button" aria-expanded="false" aria-controls="sidenav-22-8"><span>Web</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-22-8"><li class="nav-item"><a class="nav-link" href="/platform-integration/web"><div><span>Web support in Flutter</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/install-web"><div><span>Add web as build target</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/building"><div><span>Build a web app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/wasm"><div><span>Compile to WebAssembly</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/initialization"><div><span>Customize app initialization</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/embedding-flutter-web"><div><span>Add Flutter to any web app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/web-content-in-flutter"><div><span>Web content in Flutter</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/renderers"><div><span>Web renderers</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/web-images"><div><span>Display images on the web</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/faq"><div><span>Web FAQ</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-22-9" role="button" aria-expanded="false" aria-controls="sidenav-22-9"><span>Windows</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-22-9"><li class="nav-item"><a class="nav-link" href="/platform-integration/windows/install-windows"><div><span>Add Windows as build target</span></div></a></li><li class="nav-item"><a class="nav-link" href="/platform-integration/windows/building"><div><span>Build a Windows app</span></div></a></li></ul></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-23" role="button" aria-expanded="false" aria-controls="sidenav-23"><span>Packages & plugins</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-23"><li class="nav-item"><a class="nav-link" href="/packages-and-plugins/using-packages"><div><span>Use packages & plugins</span></div></a></li><li class="nav-item"><a class="nav-link" href="/packages-and-plugins/developing-packages"><div><span>Develop packages & plugins</span></div></a></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-23-3" role="button" aria-expanded="false" aria-controls="sidenav-23-3"><span>Swift Package Manager</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-23-3"><li class="nav-item"><a class="nav-link" href="/packages-and-plugins/swift-package-manager/for-app-developers"><div><span>For app developers</span></div></a></li><li class="nav-item"><a class="nav-link" href="/packages-and-plugins/swift-package-manager/for-plugin-authors"><div><span>For plugin authors</span></div></a></li></ul></li><div class="sidenav-divider"></div><li class="nav-item"><a class="nav-link" href="/packages-and-plugins/favorites"><div><span>Flutter Favorites</span></div></a></li><li class="nav-item"><a class="nav-link" href="https://pub.dev/flutter" target="_blank" rel="noopener"><div><span>Package repository</span><span class="material-symbols" aria-hidden="true">open_in_new</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-24" role="button" aria-expanded="false" aria-controls="sidenav-24"><span>Testing & debugging</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-24"><li class="nav-header">Testing</li><li class="nav-item"><a class="nav-link" href="/testing/overview"><div><span>Overview</span></div></a></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-24-3" role="button" aria-expanded="false" aria-controls="sidenav-24-3"><span>Unit testing</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-24-3"><li class="nav-item"><a class="nav-link" href="/cookbook/testing/unit/introduction"><div><span>Introduction</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/testing/unit/mocking"><div><span>Mock dependencies</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-24-4" role="button" aria-expanded="false" aria-controls="sidenav-24-4"><span>Widget testing</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-24-4"><li class="nav-item"><a class="nav-link" href="/cookbook/testing/widget/introduction"><div><span>Introduction</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/testing/widget/finders"><div><span>Find widgets</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/testing/widget/scrolling"><div><span>Simulate scrolling</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/testing/widget/tap-drag"><div><span>Simulate user interaction</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-24-5" role="button" aria-expanded="false" aria-controls="sidenav-24-5"><span>Integration testing</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-24-5"><li class="nav-item"><a class="nav-link" href="/cookbook/testing/integration/introduction"><div><span>Introduction</span></div></a></li><li class="nav-item"><a class="nav-link" href="/testing/integration-tests"><div><span>Write and run an integration test</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/testing/integration/profiling"><div><span>Profile an integration test</span></div></a></li></ul></li><li class="nav-item"><a class="nav-link" href="/testing/testing-plugins"><div><span>Test a plugin</span></div></a></li><li class="nav-item"><a class="nav-link" href="/testing/plugins-in-tests"><div><span>Handle plugin code in tests</span></div></a></li><li class="nav-header">Debugging</li><li class="nav-item"><a class="nav-link" href="/testing/debugging"><div><span>Debugging tools</span></div></a></li><li class="nav-item"><a class="nav-link" href="/testing/code-debugging"><div><span>Debug your app programmatically</span></div></a></li><li class="nav-item"><a class="nav-link" href="/testing/native-debugging"><div><span>Use a native language debugger</span></div></a></li><li class="nav-item"><a class="nav-link" href="/testing/common-errors"><div><span>Common Flutter errors</span></div></a></li><li class="nav-item"><a class="nav-link" href="/testing/errors"><div><span>Handle errors</span></div></a></li><li class="nav-item"><a class="nav-link" href="/cookbook/maintenance/error-reporting"><div><span>Report errors to a service</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-25" role="button" aria-expanded="false" aria-controls="sidenav-25"><span>Performance & optimization</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-25"><li class="nav-item"><a class="nav-link" href="/perf"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/impeller"><div><span>Impeller</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/best-practices"><div><span>Performance best practices</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/app-size"><div><span>App size</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/deferred-components"><div><span>Deferred components</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/rendering-performance"><div><span>Rendering performance</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/ui-performance"><div><span>Performance profiling</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/web-performance"><div><span>Performance profiling for web</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/metrics"><div><span>Performance metrics</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/isolates"><div><span>Concurrency and isolates</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/faq"><div><span>Performance FAQ</span></div></a></li><li class="nav-item"><a class="nav-link" href="/perf/appendix"><div><span>Appendix</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-26" role="button" aria-expanded="false" aria-controls="sidenav-26"><span>Deployment</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-26"><li class="nav-item"><a class="nav-link" href="/deployment/obfuscate"><div><span>Obfuscate Dart code</span></div></a></li><li class="nav-item"><a class="nav-link" href="/deployment/flavors"><div><span>Create app flavors for Android</span></div></a></li><li class="nav-item"><a class="nav-link" href="/deployment/flavors-ios"><div><span>Create app flavors for iOS and macOS</span></div></a></li><li class="nav-item"><a class="nav-link" href="/deployment/android"><div><span>Build and release an Android app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/deployment/ios"><div><span>Build and release an iOS app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/deployment/macos"><div><span>Build and release a macOS app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/deployment/linux"><div><span>Build and release a Linux app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/deployment/windows"><div><span>Build and release a Windows app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/deployment/web"><div><span>Build and release a web app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/deployment/cd"><div><span>Set up continuous deployment</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-27" role="button" aria-expanded="false" aria-controls="sidenav-27"><span>Add to an existing app</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-27"><li class="nav-item"><a class="nav-link" href="/add-to-app"><div><span>Introduction</span></div></a></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-27-2" role="button" aria-expanded="false" aria-controls="sidenav-27-2"><span>Add to an Android app</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-27-2"><li class="nav-item"><a class="nav-link" href="/add-to-app/android/project-setup"><div><span>Set up Android project</span></div></a></li><li class="nav-item"><a class="nav-link" href="/add-to-app/android/add-flutter-screen"><div><span>Add a single Flutter screen</span></div></a></li><li class="nav-item"><a class="nav-link" href="/add-to-app/android/add-flutter-fragment"><div><span>Add a Flutter Fragment</span></div></a></li><li class="nav-item"><a class="nav-link" href="/add-to-app/android/add-flutter-view"><div><span>Add a Flutter View</span></div></a></li><li class="nav-item"><a class="nav-link" href="/add-to-app/android/plugin-setup"><div><span>Use a Flutter plugin</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-27-3" role="button" aria-expanded="false" aria-controls="sidenav-27-3"><span>Add to an iOS app</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-27-3"><li class="nav-item"><a class="nav-link" href="/add-to-app/ios/project-setup"><div><span>Set up iOS project</span></div></a></li><li class="nav-item"><a class="nav-link" href="/add-to-app/ios/add-flutter-screen"><div><span>Add a single Flutter screen</span></div></a></li></ul></li><li class="nav-item"><a class="nav-link" href="/platform-integration/web/embedding-flutter-web"><div><span>Add to a web app</span></div></a></li><li class="nav-item"><a class="nav-link" href="/add-to-app/debugging"><div><span>Debug embedded Flutter module</span></div></a></li><li class="nav-item"><a class="nav-link" href="/add-to-app/multiple-flutters"><div><span>Add multiple Flutter instances</span></div></a></li><li class="nav-item"><a class="nav-link" href="/add-to-app/performance"><div><span>Loading sequence and performance</span></div></a></li></ul></li><li aria-hidden="true"><div class="sidenav-divider"></div></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-29" role="button" aria-expanded="false" aria-controls="sidenav-29"><span>Tools & editors</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-29"><li class="nav-item"><a class="nav-link" href="/tools/android-studio"><div><span>Android Studio & IntelliJ</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/vs-code"><div><span>Visual Studio Code</span></div></a></li><li class="nav-item"><button class="nav-link collapsible collapsed" data-toggle="collapse" data-target="#sidenav-29-3" role="button" aria-expanded="false" aria-controls="sidenav-29-3"><span>DevTools</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-29-3"><li class="nav-item"><a class="nav-link" href="/tools/devtools"><div><span>Overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/android-studio"><div><span>Run from Android Studio & IntelliJ</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/vscode"><div><span>Run from VS Code</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/cli"><div><span>Run from command line</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/inspector"><div><span>Flutter inspector</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/legacy-inspector"><div><span>Legacy Flutter inspector</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/performance"><div><span>Performance view</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/cpu-profiler"><div><span>CPU Profiler view</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/memory"><div><span>Memory view</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/console"><div><span>Debug console view</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/network"><div><span>Network view</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/debugger"><div><span>Debugger</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/logging"><div><span>Logging view</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/app-size"><div><span>App size tool</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/extensions"><div><span>DevTools extensions</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/deep-links"><div><span>Validate deep links</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/devtools/release-notes"><div><span>Release notes</span></div></a></li></ul></li><li class="nav-item"><a class="nav-link" href="/tools/sdk"><div><span>SDK overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/pubspec"><div><span>Flutter's pubspec options</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/flutter-fix"><div><span>Automated fixes</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/formatting"><div><span>Code formatting</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-30" role="button" aria-expanded="false" aria-controls="sidenav-30"><span>Flutter concepts</span> <span class="material-symbols expander" aria-hidden="true">expand_more</span></button><ul class="nav collapse" id="sidenav-30"><li class="nav-item"><a class="nav-link" href="/resources/architectural-overview"><div><span>Architectural overview</span></div></a></li><li class="nav-item"><a class="nav-link" href="/resources/inside-flutter"><div><span>Inside Flutter</span></div></a></li><li class="nav-item"><a class="nav-link" href="/ui/layout/constraints"><div><span>Understanding constraints</span></div></a></li><li class="nav-item"><a class="nav-link" href="/testing/build-modes"><div><span>Flutter's build modes</span></div></a></li><li class="nav-item"><a class="nav-link" href="/tools/hot-reload"><div><span>Hot reload</span></div></a></li></ul></li><li class="nav-item"><button class="nav-link collapsed collapsible" data-toggle="collapse" data-target="#sidenav-31" role="button" aria-expanded="false" 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href="#mvvm">MVVM</a></li></ul></li><li class="toc-entry nav-item"><a class="nav-link" href="#ui-layer">UI layer</a><ul class="nav"><li class="toc-entry nav-item"><a class="nav-link" href="#views">Views</a></li><li class="toc-entry nav-item"><a class="nav-link" href="#view-models">View models</a></li></ul></li><li class="toc-entry nav-item"><a class="nav-link" href="#data-layer">Data layer</a><ul class="nav"><li class="toc-entry nav-item"><a class="nav-link" href="#repositories">Repositories</a></li><li class="toc-entry nav-item"><a class="nav-link" href="#services">Services</a></li></ul></li><li class="toc-entry nav-item"><a class="nav-link" href="#optional-domain-layer">Optional: Domain layer</a><ul class="nav"><li class="toc-entry nav-item"><a class="nav-link" href="#data-access-with-use-cases">Data access with use-cases</a></li></ul></li><li class="toc-entry nav-item"><a class="nav-link" href="#feedback">Feedback</a></li></ul></div><article><header class="site-content__title"><h1 id="document-title">Guide to app architecture</h1><nav class="breadcrumbs" aria-label="breadcrumb"><ol vocab="https://schema.org/" typeof="BreadcrumbList"><li class="breadcrumb-item" property="itemListElement" typeof="ListItem"><a href="/app-architecture" property="item" typeof="WebPage"><span property="name">Architecture</span></a><meta property="position" content="0"><span class="material-symbols child-icon" aria-hidden="true">chevron_right</span></li><li class="breadcrumb-item active" property="itemListElement" typeof="ListItem" aria-current="page"><a href="/app-architecture/guide" property="item" typeof="WebPage"><span property="name">Architecture guide</span></a><meta property="position" content="1"></li></ol></nav></header><div id="site-toc--inline" class="site-toc toc-collapsible toc-collapsed"><header class="site-toc__title">Contents <span class="site-toc--inline__toggle toc-toggle-down" title="Expand table of contents"><i class="material-symbols" aria-hidden="true">keyboard_arrow_down</i></span> <span class="site-toc--inline__toggle toc-toggle-up" title="Collapse table of contents"><i class="material-symbols" aria-hidden="true">keyboard_arrow_up</i></span></header><ul class="section-nav"><li class="toc-entry"><a href="#overview-of-project-structure">Overview of project structure</a><ul><li class="toc-entry"><a href="#mvvm">MVVM</a></li></ul></li><li class="toc-entry"><a href="#ui-layer">UI layer</a><ul><li class="toc-entry"><a href="#views">Views</a></li><li class="toc-entry"><a href="#view-models">View models</a></li></ul></li><li class="toc-entry"><a href="#data-layer">Data layer</a><ul><li class="toc-entry"><a href="#repositories">Repositories</a></li><li class="toc-entry"><a href="#services">Services</a></li></ul></li><li class="toc-entry"><a href="#optional-domain-layer">Optional: Domain layer</a><ul><li class="toc-entry"><a href="#data-access-with-use-cases">Data access with use-cases</a></li></ul></li><li class="toc-entry"><a href="#feedback">Feedback</a></li></ul><span class="site-toc--inline__toggle toc-toggle-more-items" title="Expand table of contents"><i class="material-symbols" aria-hidden="true">more_horiz</i></span></div><p>The following pages demonstrate how to build an app using best practices. The recommendations in this guide can be applied to most apps, making them easier to scale, test, and maintain. However, they're guidelines, not steadfast rules, and you should adapt them to your unique requirements.</p><p>This section provides a high-level overview of how Flutter applications can be architected. It explains the layers of an application, along with the classes that exist within each layer. The section after this provides concrete code samples and walks through a Flutter application that's implemented these recommendations.</p><div class="header-wrapper"><h2 id="overview-of-project-structure">Overview of project structure</h2><a class="heading-link" href="#overview-of-project-structure" aria-label="Link to 'Overview of project structure' section">#</a></div><p><a href="https://en.wikipedia.org/wiki/Separation_of_concerns">Separation-of-concerns</a> is the most important principle to follow when designing your Flutter app. Your Flutter application should split into two broad layers, the UI layer and the Data layer.</p><p>Each layer is further split into different components, each of which has distinct responsibilities, a well-defined interface, boundaries and dependencies. This guide recommends you split your application into the following components:</p><ul><li>Views</li><li>View models</li><li>Repositories</li><li>Services</li></ul><div class="header-wrapper"><h3 id="mvvm">MVVM</h3><a class="heading-link" href="#mvvm" aria-label="Link to 'MVVM' section">#</a></div><p>If you've encountered the <a href="https://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93viewmodel">Model-View-ViewModel architectural pattern</a> (MVVM), this will be familiar. MVVM is an architectural pattern that separates a feature of an application into three parts: the <code>Model</code>, the <code>ViewModel</code> and the <code>View</code>. Views and view models make up the UI layer of an application. Repositories and services represent the data of an application, or the model layer of MVVM. Each of these components is defined in the next section.</p><img src="/assets/images/docs/app-architecture/guide/mvvm-intro-with-layers.png" alt="MVVM architectural pattern"><p>Every feature in an application will contain one view to describe the UI and one view model to handle logic, one or more repositories as the sources of truth for your application data, and zero or more services that interact with external APIs, like client servers and platform plugins.</p><p>A single feature of an application might require all of the following objects:</p><img src="/assets/images/docs/app-architecture/guide/feature-architecture-example.png" alt="An example of the Dart objects that might exist in one feature using the architecture described on page."><p>Each of these objects and the arrows that connect them will be explained thoroughly by the end of this page. Throughout this guide, the following simplified version of that diagram will be used as an anchor.</p><img src="/assets/images/docs/app-architecture/guide/feature-architecture-simplified.png" alt="A simplified diagram of the architecture described on this page."><aside class="alert alert-info"><div class="alert-header"><i class="material-symbols" aria-hidden="true">info</i> <span>Note</span></div><div class="alert-content"><p>Apps with complex logic might also have a logic layer that sits in between the UI layer and data layer. This logic layer is commonly called the <em>domain layer.</em> The domain layer contains additional components often called <em>interactors</em> or <em>use-cases</em>. The domain layer is covered later in this guide.</p></div></aside><div class="header-wrapper"><h2 id="ui-layer">UI layer</h2><a class="heading-link" href="#ui-layer" aria-label="Link to 'UI layer' section">#</a></div><p>An application's UI layer is responsible for interacting with the user. It displays an application's data to the user and receives user input, such as tap events and form inputs.</p><p>The UI reacts to data changes or user input. When the UI receives new data from a Repository, it should re-render to display that new data. When the user interacts with the UI, it should change to reflect that interaction.</p><p>The UI layer is made up of two architectural components, based on the MVVM design pattern:</p><ul><li><strong>Views</strong> describe how to present application data to the user. Specifically, they refer to <em>compositions of widgets</em> that make a feature. For instance, a view is often (but not always) a screen that has a <code>Scaffold</code> widget, along with all of the widgets below it in the widget tree. Views are also responsible for passing events to the view model in response to user interactions.</li><li><strong>View models</strong> contain the logic that converts app data into <em>UI State</em>, because data from repositories is often formatted differently from the data that needs to be displayed. For example, you might need to combine data from multiple repositories, or you might want to filter a list of data records.</li></ul><p>Views and view models should have a 1:1 relationship.</p><img src="/assets/images/docs/app-architecture/guide/feature-architecture-simplified-UI-highlighted.png" alt="A simplified diagram of the architecture described on this page with the view and view model objects highlighted."><p>In the simplest terms, a view model manages the UI state and the view displays that state. Using views and view models, your UI layer can maintain state during configuration changes (such as screen rotations), and you can test the logic of your UI independently of Flutter widgets.</p><aside class="alert alert-info"><div class="alert-header"><i class="material-symbols" aria-hidden="true">info</i> <span>Note</span></div><div class="alert-content"><p>'View' is an abstract term, and one view doesn't equal one widget. Widgets are composable, and several can be combined to create one view. Therefore, view models don't have a 1-to-1 relationship with widgets, but rather a 1-to-1 relationship with a <em>collection</em> of widgets.</p></div></aside><p>A feature of an application is user centric, and therefore defined by the UI layer. Every instance of a paired <em>view</em> and <em>view model</em> defines one feature in your app. This is often a screen in your app, but it doesn't have to be. For example, consider logging in and out. Logging in is generally done on a specific screen whose only purpose is to provide the user with a way to log in. In the application code, the login screen would be made up of a <code>LoginViewModel</code> class and a <code>LoginView</code> class.</p><p>On the other hand, logging out of an app is generally not done on a dedicated screen. The ability to log out is generally presented to the user as a button in a menu, a user account screen, or any number of different locations. It's often presented in multiple locations. In such scenarios, you might have a <code>LogoutViewModel</code> and a <code>LogoutView</code> which only contains a single button that can be dropped into other widgets.</p><div class="header-wrapper"><h3 id="views">Views</h3><a class="heading-link" href="#views" aria-label="Link to 'Views' section">#</a></div><p>In Flutter, views are the widget classes of your application. Views are the primary method of rendering UI, and shouldn't contain any business logic. They should be passed all data they need to render from the view model.</p><img src="/assets/images/docs/app-architecture/guide/feature-architecture-simplified-View-highlighted.png" alt="A simplified diagram of the architecture described on this page with the view object highlighted."><p>The only logic a view should contain is:</p><ul><li>Simple if-statements to show and hide widgets based on a flag or nullable field in the view model</li><li>Animation logic</li><li>Layout logic based on device information, like screen size or orientation.</li><li>Simple routing logic</li></ul><p>All logic related to data should be handled in the view model.</p><div class="header-wrapper"><h3 id="view-models">View models</h3><a class="heading-link" href="#view-models" aria-label="Link to 'View models' section">#</a></div><p>A view model exposes the application data necessary to render a view. In the architecture design described on this page, most of the logic in your Flutter application lives in view models.</p><img src="/assets/images/docs/app-architecture/guide/feature-architecture-simplified-ViewModel-highlighted.png" alt="A simplified diagram of the architecture described on this page with the view model object highlighted."><p>A view model's main responsibilities include:</p><ul><li>Retrieving application data from repositories and transforming it into a format suitable for presentation in the view. For example, it might filter, sort or aggregate data.</li><li>Maintaining the current state needed in the view, so that the view can rebuild without losing data. For example, it might contain boolean flags to conditionally render widgets in the view, or a field that tracks which section of a carousel is active on screen.</li><li>Exposes callbacks (called <strong>commands</strong>) to the view that can be attached to an event handler, like a button press or form submission.</li></ul><p>Commands are named for the <a href="https://en.wikipedia.org/wiki/Command_pattern">command pattern</a>, and are Dart functions that allow views to execute complex logic without knowledge of its implementation. Commands are written as members of the view model class to be called by the gesture handlers in the view class.</p><p>You can find examples of views, view models, and commands on the <a href="/app-architecture/case-study/ui-layer">UI layer</a> portion of the <a href="/app-architecture/case-study">App architecture case study</a>.</p><p>For a gentle introduction to MVVM in Flutter, check out the <a href="/get-started/fundamentals/state-management">state management fundamentals</a>.</p><div class="header-wrapper"><h2 id="data-layer">Data layer</h2><a class="heading-link" href="#data-layer" aria-label="Link to 'Data layer' section">#</a></div><p>The data layer of an app handles your business data and logic. Two pieces of architecture make up the data layer: services and repositories. These pieces should have well-defined inputs and outputs to simplify their reusability and testability.</p><img src="/assets/images/docs/app-architecture/guide/feature-architecture-simplified-Data-highlighted.png" alt="A simplified diagram of the architecture described on this page with the Data layer highlighted."><p>Using MVVM language, services and repositories make up your <em>model layer</em>.</p><div class="header-wrapper"><h3 id="repositories">Repositories</h3><a class="heading-link" href="#repositories" aria-label="Link to 'Repositories' section">#</a></div><p><a href="https://martinfowler.com/eaaCatalog/repository.html">Repository</a> classes are the source of truth for your model data. They're responsible for polling data from services, and transforming that raw data into <strong>domain models</strong>. Domain models represent the data that the application needs, formatted in a way that your view model classes can consume. There should be a repository class for each different type of data handled in your app.</p><p>Repositories handle the business logic associated with services, such as:</p><ul><li>Caching</li><li>Error handling</li><li>Retry logic</li><li>Refreshing data</li><li>Polling services for new data</li><li>Refreshing data based on user actions</li></ul><img src="/assets/images/docs/app-architecture/guide/feature-architecture-simplified-Repository-highlighted.png" alt="A simplified diagram of the architecture described on this page with the Repository object highlighted."><p>Repositories output application data as domain models. For example, a social media app might have a <code>UserProfileRepository</code> class that exposes a <code>Stream<UserProfile?></code>, which emits a new value whenever the user signs in or out.</p><p>The models output by repositories are consumed by view models. Repositories and view models have a many-to-many relationship. A view model can use many repositories to get the data it needs, and a repository can be used by many view models.</p><p>Repositories should never be aware of each other. If your application has business logic that needs data from two repositories, you should combine the data in the view model or in the domain layer, especially if your repository-to-view-model relationship is complex.</p><div class="header-wrapper"><h3 id="services">Services</h3><a class="heading-link" href="#services" aria-label="Link to 'Services' section">#</a></div><p>Services are in the lowest layer of your application. They wrap API endpoints and expose asynchronous response objects, such as <code>Future</code> and <code>Stream</code> objects. They're only used to isolate data-loading, and they hold no state. Your app should have one service class per data source. Examples of endpoints that services might wrap include:</p><ul><li>The underlying platform, like iOS and Android APIs</li><li>REST endpoints</li><li>Local files</li></ul><p>As a rule of thumb, services are most helpful when the necessary data lives outside of your application's Dart code - which is true of each of the preceding examples.</p><p>Services and repositories have a many-to-many relationship. A single Repository can use several services, and a service can be used by multiple repositories.</p><img src="/assets/images/docs/app-architecture/guide/feature-architecture-simplified-Service-highlighted.png" alt="A simplified diagram of the architecture described on this page with the Service object highlighted."><div class="header-wrapper"><h2 id="optional-domain-layer">Optional: Domain layer</h2><a class="heading-link" href="#optional-domain-layer" aria-label="Link to 'Optional: Domain layer' section">#</a></div><p>As your app grows and adds features, you may need to abstract away logic that adds too much complexity to your view models. These classes are often called interactors or <strong>use-cases</strong>.</p><p>Use-cases are responsible for making interactions between the UI and Data layers simpler and more reusable. They take data from repositories and make it suitable for the UI layer.</p><img src="/assets/images/docs/app-architecture/guide/mvvm-intro-with-domain-layer.png" alt="MVVM design pattern with an added domain layer object"><p>Use-cases are primarily used to encapsulate business logic that would otherwise live in the view model and meets one or more of the following conditions:</p><ol><li>Requires merging data from multiple repositories</li><li>Is exceedingly complex</li><li>The logic will be reused by different view models</li></ol><p>This layer is optional because not all applications or features within an application have these requirements. If you suspect your application would benefit from this additional layer, consider the pros and cons:</p><div class="table-wrapper"><table class="table table-striped"><thead><tr><th>Pros</th><th>Cons</th></tr></thead><tbody><tr><td>✅ Avoid code duplication in view models</td><td>❌ Increases complexity of your architecture, adding more classes and higher cognitive load</td></tr><tr><td>✅ Improve testability by separating complex business logic from UI logic</td><td>❌ Testing requires additional mocks</td></tr><tr><td>✅ Improve code readability in view models</td><td>❌ Adds additional boilerplate to your code</td></tr></tbody></table></div><div class="header-wrapper"><h3 id="data-access-with-use-cases">Data access with use-cases</h3><a class="heading-link" href="#data-access-with-use-cases" aria-label="Link to 'Data access with use-cases' section">#</a></div><p>Another consideration when adding a Domain layer is whether view models will continue to have access to repository data directly, or if you'll enforce view models to go through use-cases to get their data. Put another way, will you add use-cases as you need them? Perhaps when you notice repeated logic in your view models? Or, will you create a use-case each time a view model needs data, even if the logic in the use-case is simple?</p><p>If you choose to do the latter, it intensifies the earlier outlined pros and cons. Your application code will be extremely modular and testable, but it also adds a significant amount of unnecessary overhead.</p><p>A good approach is to add use-cases only when needed. If you find that your view models are accessing data through use-cases most of the time, you can always refactor your code to utilize use-cases exclusively. The example app used later in this guide has use-cases for some features, but also has view models that interact with repositories directly. A complex feature may ultimately end up looking like this:</p><p><img src="/assets/images/docs/app-architecture/guide/feature-architecture-simplified-with-logic-layer.png" alt="A simplified diagram of the architecture described on this page with a use case object."></p><p>This method of adding use-cases is defined by the following rules:</p><ul><li>Use-cases depend on repositories</li><li>Use-cases and repositories have a many-to-many relationship</li><li>View models depend on one or more use-cases <em>and</em> one or more repositories</li></ul><p>This method of using use-cases ends up looking less like a layered lasagna, and more like a plated dinner with two mains (UI and data layers) and a side (domain layer). Use-cases are just utility classes that have well-defined inputs and outputs. This approach is flexible and extendable, but it requires greater diligence to maintain order.</p><div class="header-wrapper"><h2 id="feedback">Feedback</h2><a class="heading-link" href="#feedback" aria-label="Link to 'Feedback' section">#</a></div><p>As this section of the website is evolving, we <a href="https://google.qualtrics.com/jfe/form/SV_4T0XuR9Ts29acw6?page=%22guide%22">welcome your feedback</a>!</p><nav class="site-nextprev-nav"><ul><li class="prev"><a href="/app-architecture/concepts">Common architecture concepts</a></li><li class="next"><a href="/app-architecture/case-study">Architecture case study</a></li></ul></nav><p id="page-github-links"><span>Unless stated otherwise, the documentation on this site reflects the latest stable version of Flutter. 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