Flutter - Dart API docs Flutter API reference documentation Flutter is Google's SDK for crafting beautiful, fast user experiences for mobile, web, and desktop from a single codebase. Flutter works with existing code, is used by developers and organizations around the world, and is free and open source. This API reference covers all libraries that are exported by the Flutter SDK. More Documentation This site hosts Flutter's API documentation. Other documentation can be found at the following locations: Install Flutter Flutter documentation Stable channel API reference documentation Main channel API reference documentation Contributing to Flutter Offline Documentation In addition to the online sites above, Flutter's documentation can be downloaded as an HTML documentation ZIP file for use when offline or when you have a poor internet connection. Note The offline documentation files are quite large, approximately 300MB zipped, 1GB unzipped. Offline HTML documentation ZIP bundles: Stable channel Main channel Or, you can add Flutter to the open-source Zeal app using the following XML configurations. Follow the instructions in the application for adding a feed. Stable channel Zeal XML configuration URL: api.flutter.dev/offline/flutter.xml Main channel Zeal XML configuration URL: main-api.flutter.dev/offline/flutter.xml Importing a Library Framework Libraries Libraries in the "Libraries" section below (or in the left navigation) are part of the core Flutter framework and are imported using 'package:flutter/<library>.dart', like so: import 'package:flutter/material.dart'; import 'package:flutter/services.dart'; Dart Libraries Libraries in the "Dart" section exist in the dart: namespace and are imported using 'dart:<library>', like so: import 'dart:async'; import 'dart:ui'; Except for 'dart:core', you must import a Dart library before you can use it. Supporting Libraries Libraries in other sections are supporting libraries that ship with Flutter. They are organized by package and are imported using 'package:<package>/<library>.dart', like so: import 'package:flutter_test/flutter_test.dart'; import 'package:file/local.dart'; Packages on pub.dev Flutter has a rich ecosystem of packages that have been contributed by the Flutter team and the broader open source community to a central repository. Among the thousands of packages, you'll find support for Firebase, Google Fonts, hardware services like Bluetooth and camera, new widgets and animations, and integration with other popular web services. You can browse those packages at pub.dev. Libraries animation The Flutter animation system. cupertino Flutter widgets implementing the current iOS design language. foundation Core Flutter framework primitives. gestures The Flutter gesture recognizers. material Flutter widgets implementing Material Design. painting The Flutter painting library. physics Simple one-dimensional physics simulations, such as springs, friction, and gravity, for use in user interface animations. rendering The Flutter rendering tree. scheduler The Flutter Scheduler library. semantics The Flutter semantics package. services Platform services exposed to Flutter apps. widget_previews The Flutter widget preview annotations and data classes. widgets The Flutter widgets framework. Dart dart:ui Built-in types and core primitives for a Flutter application. dart:ui_web Core dart:async Support for asynchronous programming, with classes such as Future and Stream. dart:collection Classes and utilities that supplement the collection support in dart:core. dart:convert Encoders and decoders for converting between different data representations, including JSON and UTF-8. dart:core Built-in types, collections, and other core functionality for every Dart program. dart:developer Interact with developer tools such as the debugger and inspector. dart:math Mathematical constants and functions, plus a random number generator. dart:typed_data Lists that efficiently handle fixed sized data (for example, unsigned 8 byte integers) and SIMD numeric types. VM dart:ffi Foreign Function Interface for interoperability with the C programming language. dart:io File, socket, HTTP, and other I/O support for non-web applications. dart:isolate Concurrent programming using isolates: independent workers that are similar to threads but don't share memory, communicating only via messages. Web package:web open_in_new This package exposes browser APIs. It's intended to replace dart:html and similar Dart SDK libraries. It will support access to browser APIs from Dart code compiled to either JavaScript or WebAssembly. dart:js_interop Interoperability, "interop" for short, with JavaScript and browser APIs. dart:js_interop_unsafe Utility methods to manipulate JavaScript objects dynamically. Web (Legacy) dart:html HTML elements and other resources for web-based applications that need to interact with the browser and the DOM (Document Object Model). dart:js Low-level support for interoperating with JavaScript. platform_integration android Flutter Android Embedder. ios FlutteriOS Embedder. linux Flutter Linux Embedder. macos Flutter macOS Embedder. windows Flutter Windows Embedder.