Introduction
Flutter2js is an experimental project that investigates feasibility of making Flutter apps run in browser using drawing primitives (canvas, CSS and SVG).
Licensed under the BSD 3-Clause License.
Implications of the approach
If the project gets drawing working, the approach taken by this project ("drawing, no HTML elements") has the following implications:
- All Flutter widgets will work.
- Apps look (more or less) identical to iOS/Android.
- Scrolling/animation performance is bad compared to web apps (but possibly acceptable).
- Code size and accessibility are inevitably poor compared to normal web apps.
Status
Ready
- Flutter SDK and sample apps compile
Next
- "Hello world"-like examples draw correctly
- Mouse/tap handling
You can help!
Notes for developers
Getting started
Hello world
Clone Git repository
git clone https://github.com/flutter2js/flutter2js
Try "Hello world"
cd examples/hello_world-browser
pub get
pub run webdev serve
Open browser at: http://localhost:8080/main.html
Technical details
Libraries from original Flutter SDK
Flutter SDK libraries are derived from the original Flutter SDK.
These include:
- dart:ui (original, docs)
- Because Pub doesn't allow overriding "dart:something" packages, it's exposed as "package:flutter/ui.dart".
- package:flutter (original, docs)
- package:flutter_localization (original, docs)
- package:flutter_test (original, docs)
The modifications include:
- Many classes in dart:ui such as Canvas delegate implementation to package:flutter2js or expose previously private/external fields.
- Eliminated usage of language features not supported by dart2js:
- Assertions in initializers. After dart2js started to support them, this became unnecessary.
- Some mixins (issue #23770)