## 1. Project Overview & Quickstart (flet-dev/flet) ## File: README.md --- Flet is a framework that allows building mobile, desktop and web applications in Python only without prior experience in frontend development. ###    Single code base for any device Your app will equally look great on iOS, Android, Windows, Linux, macOS and web. ###    Build an entire app in Python Build a cross-platform app without knowledge of Dart, Swift, Kotlin, HTML or JavaScript - only Python! ###    150+ built-in controls and services Beautiful UI widgets with Material and Cupertino design: layout, navigation, dialogs, charts - Flet uses Flutter to render UI. ###    50+ Python packages for iOS and Android Numpy, pandas, pydantic, cryptography, opencv, pillow and other popular libraries. ###    Full web support Flet apps run natively in modern browsers using WebAssembly and Pyodide, with no server required. Prefer server-side? Deploy as a Python web app with real-time UI updates. ###    Built-in packaging Build standalone executables or bundles for iOS, Android, Windows, Linux, macOS and web. Instantly deploy to App Store and Google Play. ###    Test on iOS and Android Test your project on your own mobile device with Flet App. See your app updates as you make changes. ###    Extensible Easily wrap any of thousands of Flutter packages to use with Flet or build new controls in pure Python using built-in UI primitives. ###    Accessible Flet is built with Flutter which has solid accessibility foundations on Android, iOS, web, and desktop. ## Flet app example Below is a simple "Counter" app, with a text field and two buttons to increment and decrement the counter value: ```python title="counter.py" import flet as ft def main(page: ft.Page): page.title = "Flet counter example" page.vertical_alignment = ft.MainAxisAlignment.CENTER input = ft.TextField(value="0", text_align=ft.TextAlign.RIGHT, width=100) def minus_click(e): input.value = str(int(input.value) - 1) def plus_click(e): input.value = str(int(input.value) + 1) page.add( ft.Row( alignment=ft.MainAxisAlignment.CENTER, controls=[ ft.IconButton(ft.Icons.REMOVE, on_click=minus_click), input, ft.IconButton(ft.Icons.ADD, on_click=plus_click), ], ) ) ft.run(main) ``` To run the app, install `flet`: ```bash pip install 'flet[all]' ``` then launch the app: ```bash flet run counter.py ``` This will open the app in a native OS window - what a nice alternative to Electron! 🙂 To run the same app as a web app use `--web` option with `flet run` command: ```bash flet run --web counter.py ``` ## Learn more * [Website](https://flet.dev) * [Documentation](https://flet.dev/docs/) * [Roadmap](https://flet.dev/roadmap) * [Apps Gallery](https://studio.flet.dev/gallery) ## Community * [Discussions](https://github.com/flet-dev/flet/discussions) * [Discord](https://discord.gg/dzWXP8SHG8) * [X (Twitter)](https://twitter.com/fletdev) * [Bluesky](https://bsky.app/profile/fletdev.bsky.social) * [Email us](mailto:hello@flet.dev) ## Contributing Want to help improve Flet? Check out the [contribution guide](CONTRIBUTING.md). --- ## File: client/ios/Runner/Assets.xcassets/LaunchImage.imageset/README.md # Launch Screen Assets You can customize the launch screen with your own desired assets by replacing the image files in this directory. You can also do it by opening your Flutter project's Xcode project with `open ios/Runner.xcworkspace`, selecting `Runner/Assets.xcassets` in the Project Navigator and dropping in the desired images. --- ## File: client/README.md # flet_view A new Flutter project. ## Getting Started This project is a starting point for a Flutter application. A few resources to get you started if this is your first Flutter project: - [Lab: Write your first Flutter app](https://flutter.dev/docs/get-started/codelab) - [Cookbook: Useful Flutter samples](https://flutter.dev/docs/cookbook) For help getting started with Flutter, view our [online documentation](https://flutter.dev/docs), which offers tutorials, samples, guidance on mobile development, and a full API reference. ## TODO * Close connection on application exit: * https://docs.flutter.dev/cookbook/networking/web-sockets * https://stackoverflow.com/questions/52074265/flutter-detect-killing-off-the-app * https://stackoverflow.com/questions/60184497/how-to-execute-code-before-app-exit-flutter * Change `base.href` for non-root apps: * https://docs.flutter.dev/development/ui/navigation/url-strategies#hosting-a-flutter-app-at-a-non-root-location --- ## File: packages/flet/README.md # Flet Flet is a framework that allows building mobile, desktop and web applications in Python only without prior experience in frontend development. ###    Single code base for any device Your app will equally look great on iOS, Android, Windows, Linux, macOS and web. ###    Build an entire app in Python Build a cross-platform app without knowledge of Dart, Swift, Kotlin, HTML or JavaScript - only Python! ###    150+ built-in controls and services Beautiful UI widgets with Material and Cupertino design: layout, navigation, dialogs, charts - Flet uses Flutter to render UI. ###    50+ Python packages for iOS and Android Numpy, pandas, pydantic, cryptography, opencv, pillow and other popular libraries. ###    Full web support Flet apps run natively in modern browsers using WebAssembly and Pyodide, with no server required. Prefer server-side? Deploy as a Python web app with real-time UI updates. ###    Built-in packaging Build standalone executables or bundles for iOS, Android, Windows, Linux, macOS and web. Instantly deploy to App Store and Google Play. ###    Test on iOS and Android Test your project on your own mobile device with Flet App. See your app updates as you make changes. ###    Extensible Easily wrap any of thousands of Flutter packages to use with Flet or build new controls in pure Python using built-in UI primitives. ###    Accessible Flet is built with Flutter which has solid accessibility foundations on Android, iOS, web, and desktop. ## Flet app example Below is a simple "Counter" app, with a text field and two buttons to increment and decrement the counter value: ```python title="counter.py" import flet as ft def main(page: ft.Page): page.title = "Flet counter example" page.vertical_alignment = ft.MainAxisAlignment.CENTER input = ft.TextField(value="0", text_align=ft.TextAlign.RIGHT, width=100) def minus_click(e): input.value = str(int(input.value) - 1) def plus_click(e): input.value = str(int(input.value) + 1) page.add( ft.Row( alignment=ft.MainAxisAlignment.CENTER, controls=[ ft.IconButton(ft.Icons.REMOVE, on_click=minus_click), input, ft.IconButton(ft.Icons.ADD, on_click=plus_click), ], ) ) ft.run(main) ``` To run the app, install `flet`: ```bash pip install 'flet[all]' ``` then launch the app: ```bash flet run counter.py ``` This will open the app in a native OS window - what a nice alternative to Electron! 🙂 To run the same app as a web app use `--web` option with `flet run` command: ```bash flet run --web counter.py ``` ## Learn more * [Website](https://flet.dev) * [Documentation](https://flet.dev/docs/) * [Roadmap](https://flet.dev/roadmap) * [Apps Gallery](https://studio.flet.dev/gallery) ## Community * [Discussions](https://github.com/flet-dev/flet/discussions) * [Discord](https://discord.gg/dzWXP8SHG8) * [X (Twitter)](https://twitter.com/fletdev) * [Bluesky](https://bsky.app/profile/fletdev.bsky.social) * [Email us](mailto:hello@flet.dev) ## Contributing Want to help improve Flet? Check out the [contribution guide](https://flet.dev/docs/contributing). --- ## File: sdk/python/packages/flet-web/src/flet_web/fastapi/README.md # Flet - a better UI for FastAPI Flet for FastAPI allows adding interactive real-time dashboards to your FastAPI app as well as host any Flet web app inside FastAPI with production-grade reliability. ## Installation ``` pip install flet-fastapi ``` ## First app Create `counter.py` with the following content: ```python import flet as ft import flet_fastapi async def main(page: ft.Page): counter = ft.Text("0", size=50, data=0) async def add_click(e): counter.data += 1 counter.value = str(counter.data) counter.update() page.floating_action_button = ft.FloatingActionButton( icon=ft.icons.ADD, on_click=add_click ) page.add( ft.Container(counter, alignment=ft.Alignment.CENTER, expand=True) ) app = flet_fastapi.app(main) ``` That's a simple app displaying a counter and a button at the right bottom to increment that counter. `flet_fastapi.app()` configures a single Flet app at the root of FastAPI app with `main()` sessions handler and the following endpoints: `/ws` (WS) - WebSocket handler for the Flet app. `/upload` (PUT) - file uploads handler. `/oauth_callback` (GET) - OAuth flow callback handler. `/` (GET) - Flet app static files with SPA catch-all handler. ## Running the app locally Install [Uvicorn](https://www.uvicorn.org/) web server: ``` pip install uvicorn ``` Start `uvicorn` with: ``` uvicorn counter:app ``` Open the browser and navigate to http://127.0.0.1:8000 to see the app running. ## Hosting multiple Flet apps under the same domain ```python import flet as ft import flet_fastapi async def root_main(page: ft.Page): page.add(ft.Text("This is root app!")) async def sub_main(page: ft.Page): page.add(ft.Text("This is sub app!")) app = flet_fastapi.FastAPI() app.mount("/sub-app", flet_fastapi.app(sub_main)) app.mount("/", flet_fastapi.app(root_main)) ``` Sub-apps must be mapped before the root Flet app as it configures catch-all `index.html` for SPA. Run the app with `uvicorn` and visit http://127.0.0.1:8000 and then http://127.0.0.1:8000/sub-app/ to see both Flet apps running. Notice the trailing slash in `/sub-app/` URL - without the slash the request will be routed to a root app. ## Adding Flet to the existing FastAPI app ```python from contextlib import asynccontextmanager import flet as ft import flet_fastapi from fastapi import FastAPI @asynccontextmanager async def lifespan(app: FastAPI): await flet_fastapi.app_manager.start() yield await flet_fastapi.app_manager.shutdown() app = FastAPI(lifespan=lifespan) async def main(page: ft.Page): page.add(ft.Text("Hello, Flet!")) app.mount("/flet-app", flet_fastapi.app(main)) ``` When adding Flet app to the existing FastAPI app you need to call `flet_fastapi.app_manager.start()` on app start and `flet_fastapi.app_manager.shutdown()` on shutdown. Use the way that best suites you: lifespan (in the example above) or app events. `app_manager.start()` method starts background tasks cleaning up expired sessions and OAuth flow states. `app_manager.shutdown()` method removes any temporary files created by a Flet app. ## Running the app in production It is recommended to run FastAPI in production with [Hypercorn](https://github.com/pgjones/hypercorn/) which is ASGI web server, but it is also possible to run FastAPI apps with [Gunicorn](https://gunicorn.org/) which is a WSGI server, but has more features, like passing proxy headers. To install Gunicorn: ``` pip install gunicorn ``` Start `gunicorn` with: ``` gunicorn -k uvicorn.workers.UvicornWorker counter:app ``` ## Reference ### Environment variables `FLET_SECRET_KEY` - secret key to sign upload requests. Must be set if upload directory is configured. `FLET_SESSION_TIMEOUT` - the number of seconds to keep session alive after user has disconnected. Default is 3,600 seconds. `FLET_OAUTH_STATE_TIMEOUT` - OAuth state lifetime, in seconds, which is a maximum allowed time between starting OAuth flow and redirecting to OAuth callback URL. Default is 600 seconds. `FLET_MAX_UPLOAD_SIZE` - max allowed size of an uploaded file, bytes. --- ## File: sdk/python/packages/flet-web/README.md # Flet Web client in Flutter [](https://pypi.org/project/flet-web) [](https://flet.dev/docs/assets/badges/docs-coverage/flet-web.svg) This package contains a compiled Flutter Flet web client. --- ## File: sdk/python/packages/flet-desktop/README.md # Flet Desktop client in Flutter [](https://pypi.org/project/flet-desktop) [](https://flet.dev/docs/assets/badges/docs-coverage/flet-desktop.svg) This package contains a compiled Flutter Flet desktop client. --- ## File: sdk/python/packages/flet-cli/README.md # Flet CLI [](https://pypi.org/project/flet-cli) [](https://flet.dev/docs/assets/badges/docs-coverage/flet-cli.svg) Flet CLI is a command-line interface tool for Flet, a framework for building interactive multi-platform applications using Python. ## Features - Create new Flet projects - Run Flet applications - Package and deploy Flet apps ## Basic Usage To create a new Flet project: ``` flet create myapp ``` ## 2. Official Technical Reference & Guides (flet-dev/website) # Website --- **THIS REPOSITORY HAS BEEN ARCHIVED.** Website is now [part of Flet monorepo](https://github.com/flet-dev/flet/tree/main/website). Read [this announcement](https://flet.dev/blog/flet-v-0-84-release-announcement) for more info. --- This website is built using [Docusaurus 2](https://v2.docusaurus.io/), a modern static website generator. View the live site at [https://flet.dev](https://flet.dev). ### Installation ``` $ yarn ``` ### Local Development ``` $ yarn start ``` This command starts a local development server and open up a browser window. Most changes are reflected live without having to restart the server. ### Build ``` $ yarn build ``` This command generates static content into the `build` directory and can be served using any static contents hosting service. ### Deployment ``` $ GIT_USER= USE_SSH=true yarn deploy ``` If you are using GitHub pages for hosting, this command is a convenient way to build the website and push to the `gh-pages` branch.