Flutter Embedding

To embed a Flutter app into your Jaspr website you need the following setup:

• Add flutter and jaspr_flutter_embed as dependencies:

  dart pub add flutter jaspr_flutter_embed
  

• Replace build_web_compilers with jaspr_web_compilers as a dev dependency:

  dart pub remove build_web_compilers
  dart pub add jaspr_web_compilers --dev
  

• Create the file web/flutter_bootstrap.js with the following content:

  {{flutter_js}}
  {{flutter_build_config}}
  

• Add the FlutterEmbedView component to your jaspr app like this:

  import 'package:jaspr_flutter_embed/jaspr_flutter_embed.dart';
  
  // import your flutter app widget
  import 'my_flutter_app.dart';
  
  // this can be any jaspr component
  class JasprApp extends StatelessComponent {
    JasprApp({super.key});
  
    Iterable<Component> build(BuildContext context) sync* {
      // this is a normal jaspr component
      yield FlutterEmbedView(
        // provide an optional loader component that will be displayed while the flutter app loads
        loader: MyCustomLoader(),
        // provide your flutter app widget
        widget: MyFlutterApp(
          // provide any widget properties or callbacks
          // this way you can pass and share state between jaspr and flutter
          // without needing js interop
          title: 'My Embedded Flutter App',
        ),
      );
    }
  }
  

• Finally, run your jaspr app as normal using jaspr serve or jaspr build.

See the documentation of FlutterEmbedView for a description of all available properties.

Deferred loading

The jaspr_flutter_embed package itself uses deferred imports internally to optimize the loading of the flutter framework. To make optimal use of lazy loading the flutter framework, you should use the FlutterEmbedView.deferred() constructor.

With this the flutter framework will automatically be lazy-loaded when rendering a FlutterEmbedView for the first time.

As a further optimization, it is also possible to preload the flutter framework by calling FlutterEmbedView.preload().

Import handling

Any code and components that use the flutter sdk can only be imported on the client, not the server. That means that when you use server-side rendering, you cannot directly import the above component into your app, or you will get a compilation error.

Instead, you need to use Darts conditional imports to only import the affected code on the client. See @Import.