Add GenAI inference task

.github/workflows/main.yaml

@@ -5,7 +5,7 @@ permissions: read-all
 
 on:
   pull_request:
-    branches: [ main ]
+    branches: [main]
   push:
     branches: [main, ffi-wrapper, ffi-wrapper-text-pkg]
   schedule:

Makefile

@@ -57,4 +57,17 @@ test_text:
 	cd packages/mediapipe-task-text/example && flutter test
 
 example_text:
-	cd packages/mediapipe-task-text/example && flutter run -d macos
+	cd packages/mediapipe-task-text/example && flutter run -d macos
+
+# GenAI ---
+generate_genai:
+	cd packages/mediapipe-task-genai && dart --enable-experiment=native-assets run ffigen --config=ffigen.yaml
+
+# Example genai invocation.
+# Note that `GEMMA_4B_CPU_URI` can either be a local path or web URL. Similar values exist for
+# 8B and GPU variants.
+#
+# For desktop development, standard environment variables like this work great.
+# $ GEMMA_4B_CPU_URI=/path/to/gemma-2b-it-cpu-int4.bin flutter run -d [macos, windows, linux]
+# For emulator or attached device testing, use `--dart-define` for the same values.
+# $ flutter run -d [<device_id>] --dart-define=GEMMA_4B_CPU_URI=https://url/to.com/gemma-2b-it-cpu-int4.bin

packages/mediapipe-core/lib/src/interface/task_options.dart

@@ -6,9 +6,12 @@ import 'dart:typed_data';
 
 import 'package:equatable/equatable.dart';
 
-/// {@template TaskOptions}
+/// {@template BaseOptions}
 /// Root class for options classes for MediaPipe tasks.
-///
+/// {@endtemplate}
+abstract class Options extends Equatable {}
+
+/// {@template TaskOptions}
 /// Implementing classes will contain two [BaseInnerTaskOptions] subclasses,
 /// including a descendent of the universal options struct, [BaseBaseOptions].
 /// The second field will be task-specific.
@@ -17,7 +20,7 @@ import 'package:equatable/equatable.dart';
 /// This implementation is not immutable to track whether `dispose` has been
 /// called. All values used by pkg:equatable are in fact immutable.
 // ignore: must_be_immutable
-abstract class BaseTaskOptions extends Equatable {
+abstract class BaseTaskOptions extends Options {
   /// {@macro TaskOptions}
   BaseTaskOptions();
 

packages/mediapipe-core/lib/src/io/ffi_utils.dart

@@ -90,11 +90,11 @@ extension DartAwarePointerChars on Pointer<Pointer<Char>> {
   ///
   /// See also:
   ///  * [toDartString], for a non-list equivalent.
-  List<String?> toDartStrings(int length) {
+  List<String> toDartStrings(int length) {
     if (isNullPointer) {
       throw Exception('Unexpectedly called `toDartStrings` on nullptr');
     }
-    final dartStrings = <String?>[];
+    final dartStrings = <String>[];
     int counter = 0;
     while (counter < length) {
       dartStrings.add(this[counter].toDartString());

packages/mediapipe-core/lib/src/io/task_options.dart

@@ -15,7 +15,7 @@ import 'third_party/mediapipe/generated/mediapipe_common_bindings.dart'
 /// should manage their [InnerTaskOptions] fields. The two suggested methods are
 /// [copyToNative] and [dispose].
 /// {@endtemplate}
-mixin TaskOptions<T extends Struct> on BaseTaskOptions {
+mixin TaskOptions<T extends Struct> on Options {
   /// {@template TaskOptions.copyToNative}
   /// Copies these task options into native memory. Any fields of type
   /// [InnerTaskOptions] should have their `assignToStruct` method called.

packages/mediapipe-core/test/io/task_options_test.dart

@@ -86,13 +86,17 @@ void main() {
         expect(ptr.ref.score_threshold, lessThan(0.90001));
         expect(ptr.ref.category_allowlist_count, 3);
         expect(
-          ptr.ref.category_allowlist.toDartStrings(3),
+          ptr.ref.category_allowlist.toDartStrings(
+            3,
+          ),
           ['good', 'great', 'best'],
         );
 
         expect(ptr.ref.category_denylist_count, 4);
         expect(
-          ptr.ref.category_denylist.toDartStrings(4),
+          ptr.ref.category_denylist.toDartStrings(
+            4,
+          ),
           ['bad', 'terrible', 'worst', 'honestly come on'],
         );
       });

packages/mediapipe-task-audio/sdk_downloads.dart

@@ -1,2 +1,4 @@
 // Generated file. Do not manually edit.
-final Map<String, Map<String, String>> sdkDownloadUrls = {};
+// Used by the flutter toolchain (via build.dart) during compilation of any
+// Flutter app using this package.
+final Map<String, Map<String, Map<String, String>>> sdkDownloadUrls = {};

packages/mediapipe-task-genai/.gitignore

@@ -0,0 +1,29 @@
+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.buildlog/
+.history
+.svn/
+migrate_working_dir/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# The .vscode folder contains launch configuration and tasks you configure in
+# VS Code which you may wish to be included in version control, so this line
+# is commented out by default.
+#.vscode/
+
+# Flutter/Dart/Pub related
+# Libraries should not include pubspec.lock, per https://dart.dev/guides/libraries/private-files#pubspeclock.
+/pubspec.lock
+**/doc/api/
+.dart_tool/
+build/

packages/mediapipe-task-genai/.metadata

@@ -0,0 +1,10 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: "bd909542a33ab1d5249363a2434ae50ee468094f"
+  channel: "master"
+
+project_type: package

packages/mediapipe-task-genai/CHANGELOG.md

@@ -0,0 +1,3 @@
+## 0.0.1
+
+* TODO: Describe initial release.

packages/mediapipe-task-genai/LICENSE

@@ -0,0 +1 @@
+TODO: Add your license here.

packages/mediapipe-task-genai/README.md

@@ -0,0 +1,39 @@
+<!--
+This README describes the package. If you publish this package to pub.dev,
+this README's contents appear on the landing page for your package.
+
+For information about how to write a good package README, see the guide for
+[writing package pages](https://dart.dev/guides/libraries/writing-package-pages).
+
+For general information about developing packages, see the Dart guide for
+[creating packages](https://dart.dev/guides/libraries/create-library-packages)
+and the Flutter guide for
+[developing packages and plugins](https://flutter.dev/developing-packages).
+-->
+
+TODO: Put a short description of the package here that helps potential users
+know whether this package might be useful for them.
+
+## Features
+
+TODO: List what your package can do. Maybe include images, gifs, or videos.
+
+## Getting started
+
+TODO: List prerequisites and provide or point to information on how to
+start using the package.
+
+## Usage
+
+TODO: Include short and useful examples for package users. Add longer examples
+to `/example` folder.
+
+```dart
+const like = 'sample';
+```
+
+## Additional information
+
+TODO: Tell users more about the package: where to find more information, how to
+contribute to the package, how to file issues, what response they can expect
+from the package authors, and more.

packages/mediapipe-task-genai/analysis_options.yaml

@@ -0,0 +1,9 @@
+include: ../analysis_options.yaml
+
+linter:
+  rules:
+    - public_member_api_docs # see https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo#documentation-dartdocs-javadocs-etc
+
+analyzer:
+  exclude:
+    - "**/mediapipe_genai_bindings.dart"

packages/mediapipe-task-genai/build.dart

@@ -0,0 +1,122 @@
+import 'dart:io';
+import 'package:native_assets_cli/native_assets_cli.dart';
+import 'package:http/http.dart' as http;
+import 'package:path/path.dart' as path;
+
+import 'sdk_downloads.dart';
+
+late File logFile;
+
+final logs = <(DateTime, String)>[];
+void log(String msg) {
+  logs.add((DateTime.now(), msg));
+  if (!logFile.parent.existsSync()) {
+    logFile.parent.createSync();
+  }
+
+  if (logFile.existsSync()) {
+    logFile.deleteSync();
+  }
+  logFile.createSync();
+  logFile.writeAsStringSync(logs
+      .map<String>((rec) => '[${rec.$1.toIso8601String()}] ${rec.$2}')
+      .toList()
+      .join('\n\n'));
+}
+
+Future<void> main(List<String> args) async {
+  final buildConfig = await BuildConfig.fromArgs(args);
+  logFile = File(
+    path.joinAll([
+      Directory.current.path, // root dir of app using `mediapipe-task-xyz`
+      'build/${buildConfig.dryRun ? "dryrun" : "live-run"}-build-log.txt',
+    ]),
+  );
+
+  log(args.join(' '));
+  final String targetOs = buildConfig.targetOs.toString();
+
+  log('dir.current: ${Directory.current.absolute.path}');
+
+  // Throw if target runtime is unsupported.
+  if (!sdkDownloadUrls.containsKey(targetOs)) {
+    throw Exception('Unsupported target OS: $targetOs. '
+        'Supported values are: ${sdkDownloadUrls.keys.toSet()}');
+  }
+
+  final buildOutput = BuildOutput();
+  buildOutput.dependencies.dependencies
+      .add(buildConfig.packageRoot.resolve('build.dart'));
+  buildOutput.dependencies.dependencies
+      .add(buildConfig.packageRoot.resolve('sdk_downloads.dart'));
+
+  final modelName = 'libllm_inference_engine';
+  final Iterable<String> archKeys;
+  if (buildConfig.dryRun) {
+    archKeys = sdkDownloadUrls[targetOs]![modelName]!.keys;
+  } else {
+    archKeys = [buildConfig.targetArchitecture.toString()];
+  }
+  for (String arch in archKeys) {
+    arch = getArchAlias(arch);
+    log("arch: $arch");
+    log("sdkDownloadUrls[targetOs]: ${sdkDownloadUrls[targetOs]}");
+    log("sdkDownloadUrls[targetOs]['$modelName']: ${sdkDownloadUrls[targetOs]![modelName]}");
+    log("sdkDownloadUrls[targetOs]['$modelName'][$arch]: ${sdkDownloadUrls[targetOs]![modelName]![arch]}");
+
+    if (!sdkDownloadUrls[targetOs]!['libllm_inference_engine']!
+        .containsKey(arch)) {
+      continue;
+    }
+    final assetUrl =
+        sdkDownloadUrls[targetOs]!['libllm_inference_engine']![arch]!;
+    final downloadFileLocation = buildConfig.outDir.resolve(
+      '${arch}_${assetUrl.split('/').last}',
+    );
+    log('downloadFileLocation: $downloadFileLocation');
+    buildOutput.assets.add(
+      Asset(
+        id: 'package:mediapipe_genai/src/io/third_party/mediapipe/generated/mediapipe_genai_bindings.dart',
+        linkMode: LinkMode.dynamic,
+        target: Target.fromArchitectureAndOs(
+            Architecture.fromString(arch), buildConfig.targetOs),
+        path: AssetAbsolutePath(downloadFileLocation),
+      ),
+    );
+    if (!buildConfig.dryRun) {
+      downloadAsset(assetUrl, downloadFileLocation);
+    }
+  }
+
+  await buildOutput.writeToFile(outDir: buildConfig.outDir);
+}
+
+Future<void> downloadAsset(String assetUrl, Uri destinationFile) async {
+  final downloadUri = Uri.parse(assetUrl);
+  final downloadedFile = File(destinationFile.toFilePath());
+  log('Saving file to ${downloadedFile.absolute.path}');
+
+  final downloadResponse = await http.get(downloadUri);
+  log('Download response: ${downloadResponse.statusCode}');
+
+  if (downloadResponse.statusCode == 200) {
+    if (downloadedFile.existsSync()) {
+      downloadedFile.deleteSync();
+    }
+    downloadedFile.createSync();
+    log('Saved file to ${downloadedFile.absolute.path}\n');
+    downloadedFile.writeAsBytes(downloadResponse.bodyBytes);
+  } else {
+    log('${downloadResponse.statusCode} :: ${downloadResponse.body}');
+    throw Exception(
+        '${downloadResponse.statusCode} :: ${downloadResponse.body}');
+  }
+}
+
+/// Translates native-assets architecture names into MediaPipe architecture names
+String getArchAlias(String arch) {
+  return <String, String>{
+        'arm': 'arm64',
+      }[arch] ??
+      arch;
+}

packages/mediapipe-task-genai/example/.gitignore

@@ -0,0 +1,43 @@
+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.buildlog/
+.history
+.svn/
+migrate_working_dir/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# The .vscode folder contains launch configuration and tasks you configure in
+# VS Code which you may wish to be included in version control, so this line
+# is commented out by default.
+#.vscode/
+
+# Flutter/Dart/Pub related
+**/doc/api/
+**/ios/Flutter/.last_build_id
+.dart_tool/
+.flutter-plugins
+.flutter-plugins-dependencies
+.pub-cache/
+.pub/
+/build/
+
+# Symbolication related
+app.*.symbols
+
+# Obfuscation related
+app.*.map.json
+
+# Android Studio will place build artifacts here
+/android/app/debug
+/android/app/profile
+/android/app/release

packages/mediapipe-task-genai/example/.metadata

@@ -0,0 +1,30 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: "86135b7774e32fa7b0ad0d116511471f36048579"
+  channel: "master"
+
+project_type: app
+
+# Tracks metadata for the flutter migrate command
+migration:
+  platforms:
+    - platform: root
+      create_revision: 86135b7774e32fa7b0ad0d116511471f36048579
+      base_revision: 86135b7774e32fa7b0ad0d116511471f36048579
+    - platform: ios
+      create_revision: 86135b7774e32fa7b0ad0d116511471f36048579
+      base_revision: 86135b7774e32fa7b0ad0d116511471f36048579
+
+  # User provided section
+
+  # List of Local paths (relative to this file) that should be
+  # ignored by the migrate tool.
+  #
+  # Files that are not part of the templates will be ignored by default.
+  unmanaged_files:
+    - 'lib/main.dart'
+    - 'ios/Runner.xcodeproj/project.pbxproj'

packages/mediapipe-task-genai/example/.vscode/launch.json

@@ -0,0 +1,16 @@
+{
+    "configurations": [
+        {
+            "name": "Flutter",
+            "request": "launch",
+            "type": "dart",
+            "env": {
+                "GEMMA_4B_CPU_URI": "https://storage.googleapis.com/random-storage-asdf/gemma/gemma-2b-it-cpu-int4.bin",
+                "GEMMA_4B_GPU_URI": "https://storage.googleapis.com/random-storage-asdf/gemma/gemma-2b-it-gpu-int4.bin",
+                "GEMMA_8B_CPU_URI": "https://storage.googleapis.com/random-storage-asdf/gemma/gemma-2b-it-cpu-int8.bin",
+                "GEMMA_8B_GPU_URI": "https://storage.googleapis.com/random-storage-asdf/gemma/gemma-2b-it-gpu-int8.bin",
+            },
+            "toolArgs": []
+        }
+    ]
+}

packages/mediapipe-task-genai/example/README.md

@@ -0,0 +1,16 @@
+# example
+
+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://docs.flutter.dev/get-started/codelab)
+- [Cookbook: Useful Flutter samples](https://docs.flutter.dev/cookbook)
+
+For help getting started with Flutter development, view the
+[online documentation](https://docs.flutter.dev/), which offers tutorials,
+samples, guidance on mobile development, and a full API reference.

packages/mediapipe-task-genai/example/analysis_options.yaml

@@ -0,0 +1,28 @@
+# This file configures the analyzer, which statically analyzes Dart code to
+# check for errors, warnings, and lints.
+#
+# The issues identified by the analyzer are surfaced in the UI of Dart-enabled
+# IDEs (https://dart.dev/tools#ides-and-editors). The analyzer can also be
+# invoked from the command line by running `flutter analyze`.
+
+# The following line activates a set of recommended lints for Flutter apps,
+# packages, and plugins designed to encourage good coding practices.
+include: package:flutter_lints/flutter.yaml
+
+linter:
+  # The lint rules applied to this project can be customized in the
+  # section below to disable rules from the `package:flutter_lints/flutter.yaml`
+  # included above or to enable additional rules. A list of all available lints
+  # and their documentation is published at https://dart.dev/lints.
+  #
+  # Instead of disabling a lint rule for the entire project in the
+  # section below, it can also be suppressed for a single line of code
+  # or a specific dart file by using the `// ignore: name_of_lint` and
+  # `// ignore_for_file: name_of_lint` syntax on the line or in the file
+  # producing the lint.
+  rules:
+    # avoid_print: false  # Uncomment to disable the `avoid_print` rule
+    # prefer_single_quotes: true  # Uncomment to enable the `prefer_single_quotes` rule
+
+# Additional information about this file can be found at
+# https://dart.dev/guides/language/analysis-options

packages/mediapipe-task-genai/example/android/.gitignore

@@ -0,0 +1,13 @@
+gradle-wrapper.jar
+/.gradle
+/captures/
+/gradlew
+/gradlew.bat
+/local.properties
+GeneratedPluginRegistrant.java
+
+# Remember to never publicly share your keystore.
+# See https://flutter.dev/docs/deployment/android#reference-the-keystore-from-the-app
+key.properties
+**/*.keystore
+**/*.jks

packages/mediapipe-task-genai/example/android/app/build.gradle

@@ -0,0 +1,40 @@
+plugins {
+    id "com.android.application"
+    id "kotlin-android"
+    // The Flutter Gradle Plugin must be applied after the Android and Kotlin Gradle plugins.
+    id "dev.flutter.flutter-gradle-plugin"
+}
+
+android {
+    namespace = "com.example.example"
+    compileSdk = flutter.compileSdkVersion
+    ndkVersion = flutter.ndkVersion
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_1_8
+        targetCompatibility = JavaVersion.VERSION_1_8
+    }
+
+    defaultConfig {
+        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
+        applicationId = "com.example.example"
+        // You can update the following values to match your application needs.
+        // For more information, see: https://docs.flutter.dev/deployment/android#reviewing-the-gradle-build-configuration.
+        minSdk = flutter.minSdkVersion
+        targetSdk = flutter.targetSdkVersion
+        versionCode = flutter.versionCode
+        versionName = flutter.versionName
+    }
+
+    buildTypes {
+        release {
+            // TODO: Add your own signing config for the release build.
+            // Signing with the debug keys for now, so `flutter run --release` works.
+            signingConfig = signingConfigs.debug
+        }
+    }
+}
+
+flutter {
+    source = "../.."
+}

packages/mediapipe-task-genai/example/android/app/src/debug/AndroidManifest.xml

@@ -0,0 +1,7 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <!-- The INTERNET permission is required for development. Specifically,
+         the Flutter tool needs it to communicate with the running application
+         to allow setting breakpoints, to provide hot reload, etc.
+    -->
+    <uses-permission android:name="android.permission.INTERNET"/>
+</manifest>

packages/mediapipe-task-genai/example/android/app/src/main/AndroidManifest.xml

@@ -0,0 +1,45 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <application
+        android:label="example"
+        android:name="${applicationName}"
+        android:icon="@mipmap/ic_launcher">
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:launchMode="singleTop"
+            android:taskAffinity=""
+            android:theme="@style/LaunchTheme"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
+            android:hardwareAccelerated="true"
+            android:windowSoftInputMode="adjustResize">
+            <!-- Specifies an Android theme to apply to this Activity as soon as
+                 the Android process has started. This theme is visible to the user
+                 while the Flutter UI initializes. After that, this theme continues
+                 to determine the Window background behind the Flutter UI. -->
+            <meta-data
+              android:name="io.flutter.embedding.android.NormalTheme"
+              android:resource="@style/NormalTheme"
+              />
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN"/>
+                <category android:name="android.intent.category.LAUNCHER"/>
+            </intent-filter>
+        </activity>
+        <!-- Don't delete the meta-data below.
+             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
+    </application>
+    <!-- Required to query activities that can process text, see:
+         https://developer.android.com/training/package-visibility and
+         https://developer.android.com/reference/android/content/Intent#ACTION_PROCESS_TEXT.
+
+         In particular, this is used by the Flutter engine in io.flutter.plugin.text.ProcessTextPlugin. -->
+    <queries>
+        <intent>
+            <action android:name="android.intent.action.PROCESS_TEXT"/>
+            <data android:mimeType="text/plain"/>
+        </intent>
+    </queries>
+</manifest>

packages/mediapipe-task-genai/example/android/app/src/main/kotlin/com/example/example/MainActivity.kt

@@ -0,0 +1,5 @@
+package com.example.example
+
+import io.flutter.embedding.android.FlutterActivity
+
+class MainActivity: FlutterActivity()

packages/mediapipe-task-genai/example/android/app/src/main/res/drawable-v21/launch_background.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Modify this file to customize your launch splash screen -->
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:drawable="?android:colorBackground" />
+
+    <!-- You can insert your own image assets here -->
+    <!-- <item>
+        <bitmap
+            android:gravity="center"
+            android:src="@mipmap/launch_image" />
+    </item> -->
+</layer-list>

packages/mediapipe-task-genai/example/android/app/src/main/res/drawable/launch_background.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Modify this file to customize your launch splash screen -->
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:drawable="@android:color/white" />
+
+    <!-- You can insert your own image assets here -->
+    <!-- <item>
+        <bitmap
+            android:gravity="center"
+            android:src="@mipmap/launch_image" />
+    </item> -->
+</layer-list>

packages/mediapipe-task-genai/example/android/app/src/main/res/values-night/styles.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is on -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <!-- Show a splash screen on the activity. Automatically removed when
+             the Flutter engine draws its first frame -->
+        <item name="android:windowBackground">@drawable/launch_background</item>
+    </style>
+    <!-- Theme applied to the Android Window as soon as the process has started.
+         This theme determines the color of the Android Window while your
+         Flutter UI initializes, as well as behind your Flutter UI while its
+         running.
+
+         This Theme is only used starting with V2 of Flutter's Android embedding. -->
+    <style name="NormalTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <item name="android:windowBackground">?android:colorBackground</item>
+    </style>
+</resources>

packages/mediapipe-task-genai/example/android/app/src/main/res/values/styles.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is off -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Light.NoTitleBar">
+        <!-- Show a splash screen on the activity. Automatically removed when
+             the Flutter engine draws its first frame -->
+        <item name="android:windowBackground">@drawable/launch_background</item>
+    </style>
+    <!-- Theme applied to the Android Window as soon as the process has started.
+         This theme determines the color of the Android Window while your
+         Flutter UI initializes, as well as behind your Flutter UI while its
+         running.
+
+         This Theme is only used starting with V2 of Flutter's Android embedding. -->
+    <style name="NormalTheme" parent="@android:style/Theme.Light.NoTitleBar">
+        <item name="android:windowBackground">?android:colorBackground</item>
+    </style>
+</resources>

packages/mediapipe-task-genai/example/android/app/src/profile/AndroidManifest.xml

@@ -0,0 +1,7 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <!-- The INTERNET permission is required for development. Specifically,
+         the Flutter tool needs it to communicate with the running application
+         to allow setting breakpoints, to provide hot reload, etc.
+    -->
+    <uses-permission android:name="android.permission.INTERNET"/>
+</manifest>

packages/mediapipe-task-genai/example/android/build.gradle

@@ -0,0 +1,18 @@
+allprojects {
+    repositories {
+        google()
+        mavenCentral()
+    }
+}
+
+rootProject.buildDir = "../build"
+subprojects {
+    project.buildDir = "${rootProject.buildDir}/${project.name}"
+}
+subprojects {
+    project.evaluationDependsOn(":app")
+}
+
+tasks.register("clean", Delete) {
+    delete rootProject.buildDir
+}

packages/mediapipe-task-genai/example/android/gradle.properties

@@ -0,0 +1,3 @@
+org.gradle.jvmargs=-Xmx4G -XX:MaxMetaspaceSize=2G -XX:+HeapDumpOnOutOfMemoryError
+android.useAndroidX=true
+android.enableJetifier=true

packages/mediapipe-task-genai/example/android/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.6.3-all.zip

packages/mediapipe-task-genai/example/android/settings.gradle

@@ -0,0 +1,25 @@
+pluginManagement {
+    def flutterSdkPath = {
+        def properties = new Properties()
+        file("local.properties").withInputStream { properties.load(it) }
+        def flutterSdkPath = properties.getProperty("flutter.sdk")
+        assert flutterSdkPath != null, "flutter.sdk not set in local.properties"
+        return flutterSdkPath
+    }()
+
+    includeBuild("$flutterSdkPath/packages/flutter_tools/gradle")
+
+    repositories {
+        google()
+        mavenCentral()
+        gradlePluginPortal()
+    }
+}
+
+plugins {
+    id "dev.flutter.flutter-plugin-loader" version "1.0.0"
+    id "com.android.application" version "7.3.0" apply false
+    id "org.jetbrains.kotlin.android" version "1.7.10" apply false
+}
+
+include ":app"

packages/mediapipe-task-genai/example/ios/.gitignore

@@ -0,0 +1,34 @@
+**/dgph
+*.mode1v3
+*.mode2v3
+*.moved-aside
+*.pbxuser
+*.perspectivev3
+**/*sync/
+.sconsign.dblite
+.tags*
+**/.vagrant/
+**/DerivedData/
+Icon?
+**/Pods/
+**/.symlinks/
+profile
+xcuserdata
+**/.generated/
+Flutter/App.framework
+Flutter/Flutter.framework
+Flutter/Flutter.podspec
+Flutter/Generated.xcconfig
+Flutter/ephemeral/
+Flutter/app.flx
+Flutter/app.zip
+Flutter/flutter_assets/
+Flutter/flutter_export_environment.sh
+ServiceDefinitions.json
+Runner/GeneratedPluginRegistrant.*
+
+# Exceptions to above rules.
+!default.mode1v3
+!default.mode2v3
+!default.pbxuser
+!default.perspectivev3

packages/mediapipe-task-genai/example/ios/Flutter/AppFrameworkInfo.plist

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+  <key>CFBundleDevelopmentRegion</key>
+  <string>en</string>
+  <key>CFBundleExecutable</key>
+  <string>App</string>
+  <key>CFBundleIdentifier</key>
+  <string>io.flutter.flutter.app</string>
+  <key>CFBundleInfoDictionaryVersion</key>
+  <string>6.0</string>
+  <key>CFBundleName</key>
+  <string>App</string>
+  <key>CFBundlePackageType</key>
+  <string>FMWK</string>
+  <key>CFBundleShortVersionString</key>
+  <string>1.0</string>
+  <key>CFBundleSignature</key>
+  <string>????</string>
+  <key>CFBundleVersion</key>
+  <string>1.0</string>
+  <key>MinimumOSVersion</key>
+  <string>12.0</string>
+</dict>
+</plist>

packages/mediapipe-task-genai/example/ios/Flutter/Debug.xcconfig

@@ -0,0 +1,2 @@
+#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.debug.xcconfig"
+#include "Generated.xcconfig"

packages/mediapipe-task-genai/example/ios/Flutter/Release.xcconfig

@@ -0,0 +1,2 @@
+#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig"
+#include "Generated.xcconfig"

packages/mediapipe-task-genai/example/ios/Podfile

@@ -0,0 +1,44 @@
+# Uncomment this line to define a global platform for your project
+# platform :ios, '12.0'
+
+# CocoaPods analytics sends network stats synchronously affecting flutter build latency.
+ENV['COCOAPODS_DISABLE_STATS'] = 'true'
+
+project 'Runner', {
+  'Debug' => :debug,
+  'Profile' => :release,
+  'Release' => :release,
+}
+
+def flutter_root
+  generated_xcode_build_settings_path = File.expand_path(File.join('..', 'Flutter', 'Generated.xcconfig'), __FILE__)
+  unless File.exist?(generated_xcode_build_settings_path)
+    raise "#{generated_xcode_build_settings_path} must exist. If you're running pod install manually, make sure flutter pub get is executed first"
+  end
+
+  File.foreach(generated_xcode_build_settings_path) do |line|
+    matches = line.match(/FLUTTER_ROOT\=(.*)/)
+    return matches[1].strip if matches
+  end
+  raise "FLUTTER_ROOT not found in #{generated_xcode_build_settings_path}. Try deleting Generated.xcconfig, then run flutter pub get"
+end
+
+require File.expand_path(File.join('packages', 'flutter_tools', 'bin', 'podhelper'), flutter_root)
+
+flutter_ios_podfile_setup
+
+target 'Runner' do
+  use_frameworks!
+  use_modular_headers!
+
+  flutter_install_all_ios_pods File.dirname(File.realpath(__FILE__))
+  target 'RunnerTests' do
+    inherit! :search_paths
+  end
+end
+
+post_install do |installer|
+  installer.pods_project.targets.each do |target|
+    flutter_additional_ios_build_settings(target)
+  end
+end

packages/mediapipe-task-genai/example/ios/Runner.xcodeproj/project.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>IDEDidComputeMac32BitWarning</key>
+	<true/>
+</dict>
+</plist>

packages/mediapipe-task-genai/example/ios/Runner.xcodeproj/project.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>PreviewsEnabled</key>
+	<false/>
+</dict>
+</plist>

packages/mediapipe-task-genai/example/ios/Runner.xcodeproj/xcshareddata/xcschemes/Runner.xcscheme

@@ -0,0 +1,98 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1510"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+               BuildableName = "Runner.app"
+               BlueprintName = "Runner"
+               ReferencedContainer = "container:Runner.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+            BuildableName = "Runner.app"
+            BlueprintName = "Runner"
+            ReferencedContainer = "container:Runner.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+      <Testables>
+         <TestableReference
+            skipped = "NO"
+            parallelizable = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "331C8080294A63A400263BE5"
+               BuildableName = "RunnerTests.xctest"
+               BlueprintName = "RunnerTests"
+               ReferencedContainer = "container:Runner.xcodeproj">
+            </BuildableReference>
+         </TestableReference>
+      </Testables>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+            BuildableName = "Runner.app"
+            BlueprintName = "Runner"
+            ReferencedContainer = "container:Runner.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Profile"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+            BuildableName = "Runner.app"
+            BlueprintName = "Runner"
+            ReferencedContainer = "container:Runner.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

packages/mediapipe-task-genai/example/ios/Runner.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>IDEDidComputeMac32BitWarning</key>
+	<true/>
+</dict>
+</plist>

packages/mediapipe-task-genai/example/ios/Runner.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>PreviewsEnabled</key>
+	<false/>
+</dict>
+</plist>

packages/mediapipe-task-genai/example/ios/Runner/AppDelegate.swift

@@ -0,0 +1,13 @@
+import Flutter
+import UIKit
+
+@main
+@objc class AppDelegate: FlutterAppDelegate {
+  override func application(
+    _ application: UIApplication,
+    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
+  ) -> Bool {
+    GeneratedPluginRegistrant.register(with: self)
+    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
+  }
+}

packages/mediapipe-task-genai/example/ios/Runner/Assets.xcassets/AppIcon.appiconset/Contents.json

@@ -0,0 +1,122 @@
+{
+  "images" : [
+    {
+      "size" : "20x20",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-20x20@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "20x20",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-20x20@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-29x29@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-29x29@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-29x29@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-40x40@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-40x40@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "60x60",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-60x60@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "60x60",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-60x60@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "20x20",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-20x20@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "20x20",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-20x20@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-29x29@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-29x29@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-40x40@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-40x40@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "76x76",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-76x76@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "76x76",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-76x76@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "83.5x83.5",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-83.5x83.5@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "1024x1024",
+      "idiom" : "ios-marketing",
+      "filename" : "Icon-App-1024x1024@1x.png",
+      "scale" : "1x"
+    }
+  ],
+  "info" : {
+    "version" : 1,
+    "author" : "xcode"
+  }
+}

packages/mediapipe-task-genai/example/ios/Runner/Assets.xcassets/LaunchImage.imageset/Contents.json

@@ -0,0 +1,23 @@
+{
+  "images" : [
+    {
+      "idiom" : "universal",
+      "filename" : "LaunchImage.png",
+      "scale" : "1x"
+    },
+    {
+      "idiom" : "universal",
+      "filename" : "LaunchImage@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "universal",
+      "filename" : "LaunchImage@3x.png",
+      "scale" : "3x"
+    }
+  ],
+  "info" : {
+    "version" : 1,
+    "author" : "xcode"
+  }
+}

packages/mediapipe-task-genai/example/ios/Runner/Assets.xcassets/LaunchImage.imageset/README.md

@@ -0,0 +1,5 @@
+# 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.

packages/mediapipe-task-genai/example/ios/Runner/Base.lproj/LaunchScreen.storyboard

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="12121" systemVersion="16G29" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" colorMatched="YES" initialViewController="01J-lp-oVM">
+    <dependencies>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="12089"/>
+    </dependencies>
+    <scenes>
+        <!--View Controller-->
+        <scene sceneID="EHf-IW-A2E">
+            <objects>
+                <viewController id="01J-lp-oVM" sceneMemberID="viewController">
+                    <layoutGuides>
+                        <viewControllerLayoutGuide type="top" id="Ydg-fD-yQy"/>
+                        <viewControllerLayoutGuide type="bottom" id="xbc-2k-c8Z"/>
+                    </layoutGuides>
+                    <view key="view" contentMode="scaleToFill" id="Ze5-6b-2t3">
+                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <subviews>
+                            <imageView opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" image="LaunchImage" translatesAutoresizingMaskIntoConstraints="NO" id="YRO-k0-Ey4">
+                            </imageView>
+                        </subviews>
+                        <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
+                        <constraints>
+                            <constraint firstItem="YRO-k0-Ey4" firstAttribute="centerX" secondItem="Ze5-6b-2t3" secondAttribute="centerX" id="1a2-6s-vTC"/>
+                            <constraint firstItem="YRO-k0-Ey4" firstAttribute="centerY" secondItem="Ze5-6b-2t3" secondAttribute="centerY" id="4X2-HB-R7a"/>
+                        </constraints>
+                    </view>
+                </viewController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="iYj-Kq-Ea1" userLabel="First Responder" sceneMemberID="firstResponder"/>
+            </objects>
+            <point key="canvasLocation" x="53" y="375"/>
+        </scene>
+    </scenes>
+    <resources>
+        <image name="LaunchImage" width="168" height="185"/>
+    </resources>
+</document>

packages/mediapipe-task-genai/example/ios/Runner/Base.lproj/Main.storyboard

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="10117" systemVersion="15F34" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" initialViewController="BYZ-38-t0r">
+    <dependencies>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="10085"/>
+    </dependencies>
+    <scenes>
+        <!--Flutter View Controller-->
+        <scene sceneID="tne-QT-ifu">
+            <objects>
+                <viewController id="BYZ-38-t0r" customClass="FlutterViewController" sceneMemberID="viewController">
+                    <layoutGuides>
+                        <viewControllerLayoutGuide type="top" id="y3c-jy-aDJ"/>
+                        <viewControllerLayoutGuide type="bottom" id="wfy-db-euE"/>
+                    </layoutGuides>
+                    <view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC">
+                        <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <color key="backgroundColor" white="1" alpha="1" colorSpace="custom" customColorSpace="calibratedWhite"/>
+                    </view>
+                </viewController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/>
+            </objects>
+        </scene>
+    </scenes>
+</document>

packages/mediapipe-task-genai/example/ios/Runner/Info.plist

@@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CADisableMinimumFrameDurationOnPhone</key>
+	<true/>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>$(DEVELOPMENT_LANGUAGE)</string>
+	<key>CFBundleDisplayName</key>
+	<string>Example</string>
+	<key>CFBundleExecutable</key>
+	<string>$(EXECUTABLE_NAME)</string>
+	<key>CFBundleIdentifier</key>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundleName</key>
+	<string>example</string>
+	<key>CFBundlePackageType</key>
+	<string>APPL</string>
+	<key>CFBundleShortVersionString</key>
+	<string>$(FLUTTER_BUILD_NAME)</string>
+	<key>CFBundleSignature</key>
+	<string>????</string>
+	<key>CFBundleVersion</key>
+	<string>$(FLUTTER_BUILD_NUMBER)</string>
+	<key>LSRequiresIPhoneOS</key>
+	<true/>
+	<key>UIApplicationSupportsIndirectInputEvents</key>
+	<true/>
+	<key>UILaunchStoryboardName</key>
+	<string>LaunchScreen</string>
+	<key>UIMainStoryboardFile</key>
+	<string>Main</string>
+	<key>UISupportedInterfaceOrientations</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+	<key>UISupportedInterfaceOrientations~ipad</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationPortraitUpsideDown</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+</dict>
+</plist>

packages/mediapipe-task-genai/example/ios/Runner/Runner-Bridging-Header.h

@@ -0,0 +1 @@
+#import "GeneratedPluginRegistrant.h"

packages/mediapipe-task-genai/example/ios/RunnerTests/RunnerTests.swift

@@ -0,0 +1,12 @@
+import Flutter
+import UIKit
+import XCTest
+
+class RunnerTests: XCTestCase {
+
+  func testExample() {
+    // If you add code to the Runner application, consider adding tests here.
+    // See https://developer.apple.com/documentation/xctest for more information about using XCTest.
+  }
+
+}

packages/mediapipe-task-genai/example/lib/fake_inference_engine.dart

@@ -0,0 +1,72 @@
+// // Copyright 2014 The Flutter Authors. All rights reserved.
+// // Use of this source code is governed by a BSD-style license that can be
+// // found in the LICENSE file.
+
+// import 'dart:async';
+// import 'dart:ffi';
+// import 'dart:math';
+
+// import 'package:logging/logging.dart';
+// import 'package:mediapipe_genai/mediapipe_genai.dart';
+
+// final _log = Logger('FakeInferenceEngine');
+
+// class FakeInferenceEngine implements LlmInferenceEngine {
+//   FakeInferenceEngine(LlmInferenceOptions options) {
+//     _log.info('Initializing FakeInferenceEngine with $options');
+//   }
+
+//   @override
+//   Stream<String> generateResponse(String text) {
+//     final controller = StreamController<String>.broadcast();
+
+//     final rnd = Random();
+//     // Delay between 500 and 1000ms
+//     Future.delayed(Duration(milliseconds: rnd.nextInt(500) + 500)).then(
+//       (_) async {
+//         final List<String> message =
+//             _genericResponses[rnd.nextInt(_genericResponses.length)];
+
+//         for (final chunk in message) {
+//           // Delay between 500 and 1000ms
+//           await Future.delayed(Duration(milliseconds: rnd.nextInt(500) + 500));
+//           controller.add(chunk);
+//         }
+//         controller.close();
+//       },
+//     );
+
+//     return controller.stream;
+//   }
+
+//   @override
+//   Future<int> sizeInTokens(String text) async =>
+//       (text.split(' ').length * 1.5).toInt();
+
+//   // These three methods, `cancel`, `dispose`, and `handleErrorMessage` serve
+//   // no purpose whatsoever for this fake implementation and should not be
+//   // necessary to implement here; but surprisingly the type system won't compile
+//   // if they aren't present. Strangely, the analysis server does not report any
+//   // issue, so the (false positive, I believe) error only arises when you run
+//   // the actual app.
+//   void cancel() => throw UnimplementedError();
+
+//   @override
+//   void dispose() => throw UnimplementedError();
+
+//   void handleErrorMessage(Pointer<Pointer<Char>> errorMessage, [int? status]) =>
+//       throw UnimplementedError();
+// }
+
+// const _genericResponses = <List<String>>[
+//   ['Hello', 'my good', 'friend!', 'How are you doing?', 'Are you well?'],
+//   ['Well now, don\'t', 'get so hasty! There are still reasonable', 'options.'],
+//   ['From what I\'m hearing,', 'it sounds like you need to dance more.'],
+//   [
+//     'I too enjoy a nice sandwich,',
+//     'but you\'ve gotta',
+//     'toast the bread - come',
+//     'on!',
+//   ],
+//   ['I don\'t appreciate that slander and', 'I own\'t', 'stand for it!'],
+// ];

packages/mediapipe-task-genai/example/lib/llm_inference_demo.dart

@@ -0,0 +1,94 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:example/bloc.dart';
+import 'package:example/model_selection_screen.dart';
+import 'package:example/models/models.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:mediapipe_genai/mediapipe_genai.dart';
+// import 'fake_inference_engine.dart';
+import 'widgets/widgets.dart';
+
+class LlmInferenceDemo extends StatefulWidget {
+  const LlmInferenceDemo({super.key});
+
+  @override
+  State<LlmInferenceDemo> createState() => _LlmInferenceDemoState();
+}
+
+class _LlmInferenceDemoState extends State<LlmInferenceDemo>
+    with AutomaticKeepAliveClientMixin<LlmInferenceDemo> {
+  final results = <Widget>[];
+
+  late TranscriptBloc bloc;
+
+  @override
+  void initState() {
+    super.initState();
+    bloc = TranscriptBloc(
+      engineBuilder: LlmInferenceEngine.new,
+      // engineBuilder: FakeInferenceEngine.new,
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    super.build(context);
+
+    return MultiBlocListener(
+      listeners: [
+        // Error listener
+        BlocListener<TranscriptBloc, TranscriptState>(
+          bloc: bloc,
+          listener: (context, TranscriptState state) {
+            if (state.error != null) {
+              ScaffoldMessenger.of(context).showSnackBar(
+                SnackBar(content: Text(state.error!)),
+              );
+            }
+          },
+        ),
+      ],
+      child: BlocBuilder(
+        bloc: bloc,
+        builder: (context, TranscriptState state) {
+          return Scaffold(
+            appBar: AppBar(title: const Text('Inference')),
+            body: SafeArea(
+              child: ModelSelectionScreen(
+                modelsReady: state.modelsReady,
+                deleteModel: (LlmModel model) => bloc.add(DeleteModel(model)),
+                downloadModel: (LlmModel model) =>
+                    bloc.add(DownloadModel(model)),
+                modelInfoMap: state.modelInfoMap,
+                selectModel: (LlmModel model) {
+                  Navigator.push(
+                    context,
+                    MaterialPageRoute(
+                      builder: (context) => ChatScreen(
+                        bloc,
+                        model: model,
+                        key: ValueKey(model.displayName),
+                      ),
+                    ),
+                  );
+                },
+              ),
+            ),
+          );
+        },
+      ),
+    );
+  }
+
+  @override
+  bool get wantKeepAlive => true;
+
+  @override
+  void dispose() {
+    bloc.close();
+    super.dispose();
+  }
+}

packages/mediapipe-task-genai/example/lib/logging.dart

@@ -0,0 +1,21 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:io' as io;
+import 'package:logging/logging.dart';
+
+final log = Logger('Genai');
+
+void initLogging() {
+  Logger.root.level = Level.FINEST;
+  Logger.root.onRecord.listen((record) {
+    io.stdout.writeln('${record.level.name} [${record.loggerName}]'
+        '['
+        '${record.time.hour.toString()}:'
+        '${record.time.minute.toString().padLeft(2, "0")}:'
+        '${record.time.second.toString().padLeft(2, "0")}.'
+        '${record.time.millisecond.toString().padRight(3, "0")}'
+        '] ${record.message}');
+  });
+}

packages/mediapipe-task-genai/example/lib/main.dart

@@ -0,0 +1,119 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:flutter_localizations/flutter_localizations.dart';
+import 'package:logging/logging.dart';
+import 'llm_inference_demo.dart';
+import 'logging.dart';
+
+/// {@template AppBlocObserver}
+/// Logger of all things related to `pkg:flutter_bloc`.
+/// {@endtemplate}
+class AppBlocObserver extends BlocObserver {
+  /// {@macro AppBlocObserver}
+  const AppBlocObserver();
+
+  static final _log = Logger('AppBlocObserver');
+
+  @override
+  void onChange(BlocBase<dynamic> bloc, Change<dynamic> change) {
+    _log.finer('onChange(${bloc.runtimeType}, $change)');
+    super.onChange(bloc, change);
+  }
+
+  @override
+  void onEvent(Bloc<dynamic, dynamic> bloc, Object? event) {
+    _log.finer('onEvent($event)');
+    super.onEvent(bloc, event);
+  }
+
+  @override
+  void onError(BlocBase<dynamic> bloc, Object error, StackTrace stackTrace) {
+    // print('onError(${bloc.runtimeType}, $error, $stackTrace)');
+    super.onError(bloc, error, stackTrace);
+  }
+}
+
+void main() {
+  initLogging();
+  Bloc.observer = const AppBlocObserver();
+  runApp(
+    const MaterialApp(
+      localizationsDelegates: [
+        GlobalMaterialLocalizations.delegate,
+        GlobalWidgetsLocalizations.delegate,
+        GlobalCupertinoLocalizations.delegate, // This is required
+      ],
+      home: MainApp(),
+    ),
+  );
+}
+
+class MainApp extends StatefulWidget {
+  const MainApp({super.key});
+
+  @override
+  State<MainApp> createState() => _MainAppState();
+}
+
+class _MainAppState extends State<MainApp> {
+  final PageController controller = PageController();
+
+  final titles = <String>['Inference'];
+  int titleIndex = 0;
+
+  void switchToPage(int index) {
+    controller.animateToPage(
+      index,
+      duration: const Duration(milliseconds: 200),
+      curve: Curves.easeOut,
+    );
+    setState(() {
+      titleIndex = index;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    const activeTextStyle = TextStyle(
+      fontWeight: FontWeight.bold,
+      color: Colors.orange,
+    );
+    const inactiveTextStyle = TextStyle(
+      color: Colors.white,
+    );
+    return Scaffold(
+      body: PageView(
+        controller: controller,
+        children: const <Widget>[
+          LlmInferenceDemo(),
+        ],
+      ),
+      bottomNavigationBar: SizedBox(
+        height: 50 + MediaQuery.of(context).viewPadding.bottom / 2,
+        child: ColoredBox(
+          color: Colors.blueGrey,
+          child: Column(
+            children: [
+              Row(
+                mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+                children: <Widget>[
+                  TextButton(
+                    onPressed: () => switchToPage(0),
+                    child: Text(
+                      'Inference',
+                      style:
+                          titleIndex == 0 ? activeTextStyle : inactiveTextStyle,
+                    ),
+                  ),
+                ],
+              ),
+              SizedBox(
+                height: MediaQuery.of(context).viewPadding.bottom / 2,
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}

packages/mediapipe-task-genai/example/lib/model_location_provider.dart

@@ -0,0 +1,243 @@
+import 'dart:async';
+import 'dart:io';
+import 'package:example/models/models.dart';
+import 'package:example/model_storage/model_storage.dart';
+import 'package:http/http.dart' as http;
+import 'package:logging/logging.dart';
+
+final _log = Logger('ModelLocationProvider');
+
+/// Provides the locations of a given [LlmModel].
+///
+/// There are two constructors, but [fromEnvironment] is expected to be the most
+/// useful assuming the Flutter application was build with the
+/// `--dart-define=GEMMA_8B_GPU_PATH=<location>` flags, or similar, depending
+/// on which models the developer and user intend to use.
+///
+/// Usage:
+/// ```dart
+/// final provider = ModelLocationProvider.fromEnvironment();
+/// (Future<String> locationFuture, Stream<int> downloadProgress,) =
+///    await provider.getModelLocation(LlmModel.gemma8bGpu);
+/// if (downloadProgress != null) {
+///   await for (final percent in downloadProgress) {
+///     showDownloadPercentage(percent);
+///   }
+/// }
+/// // Should complete instantly
+/// final location = await locationFuture;
+/// ```
+///
+/// See also:
+///  * [LlmModel], the enum which tracks each available LLM.
+class ModelLocationProvider {
+  ModelLocationProvider._({required ModelPaths modelLocations}) {
+    storage = ModelStorage()
+      ..setInitialModelLocations(modelLocations).then(
+        (_) {
+          _ready.complete();
+        },
+      );
+  }
+  factory ModelLocationProvider.fromEnvironment() {
+    return ModelLocationProvider._(
+      modelLocations: ModelLocationProvider._getModelLocationsFromEnvironment(),
+    );
+  }
+
+  late final ModelStorageInterface storage;
+
+  final _ready = Completer<void>();
+  Future<void> get ready => _ready.future;
+
+  // Useful for quick development if there is any friction around passing
+  // environment variables
+  static const hardcodedLocations = <LlmModel, String>{
+    LlmModel.gemma4bCpu:
+        'https://storage.googleapis.com/random-storage-asdf/gemma/gemma-2b-it-cpu-int4.bin',
+    LlmModel.gemma4bGpu:
+        'https://storage.googleapis.com/random-storage-asdf/gemma/gemma-2b-it-gpu-int4.bin',
+    LlmModel.gemma8bCpu:
+        'https://storage.googleapis.com/random-storage-asdf/gemma/gemma-2b-it-cpu-int8.bin',
+    LlmModel.gemma8bGpu:
+        'https://storage.googleapis.com/random-storage-asdf/gemma/gemma-2b-it-gpu-int8.bin',
+  };
+
+  static ModelPaths _getModelLocationsFromEnvironment() {
+    final locations = <LlmModel, String>{};
+    for (final model in LlmModel.values) {
+      String location = hardcodedLocations[model] ??
+          Platform.environment[model.environmentVariableUriName] ??
+          model.dartDefine;
+
+      // `model.dartDefine` has an empty state of an empty string, not null,
+      // which is why `location` is a `String` and not a `String?`
+      if (location.isNotEmpty) {
+        locations[model] = location;
+      }
+    }
+    return locations;
+  }
+
+  /// {@macro downloadExists}
+  Future<bool> downloadExists(String downloadLocation) =>
+      storage.downloadExists(downloadLocation);
+
+  Future<bool> downloadExistsForModel(LlmModel model) async {
+    String? path = storage.pathFor(model);
+    return path == null ? false : storage.downloadExists(path);
+  }
+
+  Future<void> delete(LlmModel model) async => await storage.delete(model);
+
+  /// {@macro binarySize}
+  int binarySize(String location) => storage.binarySize(location);
+
+  /// Accepts a model and returns the size on disk for said model if it is
+  /// already downloaded and fully available.
+  int? binarySizeForModel(LlmModel model) {
+    final location = pathFor(model);
+    return location != null ? storage.binarySize(location) : null;
+  }
+
+  /// {@macro pathFor}
+  String? pathFor(LlmModel model) => storage.pathFor(model);
+
+  /// {@macro urlFor}
+  Uri? urlFor(LlmModel model) => storage.urlFor(model);
+
+  /// Storage for the controllers tied to in-progress downloads, each of which
+  /// should emit download progress updates as a percentage.
+  final _downloadControllers = <LlmModel, StreamController<int>>{};
+
+  /// Asychronously returns the String for the location of a locally available
+  /// copy of the requested model and an optional download progress stream if
+  /// the model is downloading.
+  Future<(Future<String>, Stream<int>?)> getModelLocation(
+    LlmModel model,
+  ) async {
+    await ready;
+    final path = storage.pathFor(model);
+    if (path != null) {
+      if (!await storage.downloadExists(path)) {
+        throw Exception(
+          'Location $path for $model was expected to have a file, but it is '
+          'missing.',
+        );
+      }
+
+      final binarySize = storage.binarySize(path);
+      if (binarySize > 0) {
+        _log.finer(
+          'Returning already downloaded model for $model of '
+          '$binarySize bytes',
+        );
+        return (Future.value(path), null);
+      }
+      _log.finer('Deleting existing $model of 0 bytes');
+      storage.delete(model);
+    }
+
+    final url = storage.urlFor(model);
+    if (url != null) {
+      return _getOrStartDownload(model, url);
+    }
+    throw Exception(
+      'ModelLocationProvider does not know where to find a '
+      '${model.name} model, either on disk or elsewhere. Did you include a '
+      'clause like `${model.environmentVariableUriName}=<location>` before '
+      '`flutter run`? See the example README for more details.',
+    );
+  }
+
+  /// Either initiates a fresh download or returns an ongoing download.
+  Future<(Future<String>, Stream<int>?)> _getOrStartDownload(
+    LlmModel model,
+    Uri url,
+  ) async {
+    final downloadDestination = await storage.urlToDownloadDestination(url);
+
+    // This is the way to figure out if the file is still being downloaded.
+    // If there is a download controller for the model, we must await its
+    // completion.
+    if (!_downloadControllers.containsKey(model)) {
+      return (
+        Future.value(downloadDestination),
+        await _downloadFile(model, url, downloadDestination)
+      );
+    }
+    return (
+      Future.value(downloadDestination),
+      _downloadControllers[model]!.stream
+    );
+  }
+
+  /// Downloads the file, creating and updating a stream with progress.
+  ///
+  /// This method does not return the location of the file, and in fact should
+  /// not be called directly. Call [getModelLocation], which makes use of
+  /// [_getOrStartDownload] if the file is not yet available on disk.
+  Future<Stream<int>> _downloadFile(
+    LlmModel model,
+    Uri location,
+    String downloadDestination,
+  ) async {
+    // Prepare a place for the file to be downloaded.
+    if (await storage.downloadExists(downloadDestination)) {
+      throw Exception('File exists at LLM model location in _downloadFile, '
+          'which expects to only be called when said model location is empty. '
+          'Unexpectedly occupied file location was ${location.path}');
+    }
+    final downloadSink = await storage.create(downloadDestination);
+
+    // Setup the request itself and read preliminary headers.
+    final request = http.Request('GET', location);
+    final response = await request.send();
+    final contentLength = int.parse(response.headers['content-length']!);
+    _log.finer('File download: $contentLength bytes');
+    final downloadCompleter = Completer<bool>();
+    int downloadedBytes = 0;
+    int lastPercentEmitted = 0;
+
+    // Setup our reporting stream. Use a broadcast stream because calls to
+    // `_getOrStartDownload` will need to resubscribe if the file is already
+    // being downloaded.
+    _downloadControllers[model] = StreamController<int>.broadcast();
+
+    // Actually begin downloading
+    response.stream.listen(
+      (List<int> bytes) {
+        downloadSink.add(bytes);
+        downloadedBytes += bytes.length;
+        int percent = ((downloadedBytes / contentLength) * 100).toInt();
+        if ((percent > lastPercentEmitted)) {
+          _log.finest('ModelLocationProvider :: $percent%');
+          _downloadControllers[model]!.add(percent);
+          lastPercentEmitted = percent;
+        }
+      },
+      onDone: () => downloadCompleter.complete(true),
+      onError: (error, stacktrace) {
+        _log.shout('error: $error');
+        _log.shout('stacktrace: $stacktrace');
+        downloadCompleter.complete(false);
+      },
+    );
+    downloadCompleter.future.then((downloadSuccessful) async {
+      if (downloadSuccessful) {
+        // Setting this value marks the model binary as fully downloaded.
+        storage.setPathCache(model, downloadDestination);
+        storage.close(downloadDestination);
+      } else {
+        // If the download did not complete, remove a partial download
+        storage.abort(downloadDestination);
+      }
+      // Clean-up resources
+      // Closing this controller is what signals to outside code that the file
+      // download is complete.
+      _downloadControllers[model]?.close();
+      _downloadControllers.remove(model);
+    });
+    return _downloadControllers[model]!.stream;
+  }
+}

packages/mediapipe-task-genai/example/lib/model_selection_screen.dart

@@ -0,0 +1,223 @@
+// import 'package:example/bloc.dart';
+import 'dart:math';
+
+import 'package:adaptive_dialog/adaptive_dialog.dart';
+import 'package:example/models/llm_model.dart';
+import 'package:flutter/material.dart';
+import 'package:getwidget/getwidget.dart';
+
+class ModelSelectionScreen extends StatelessWidget {
+  const ModelSelectionScreen({
+    required this.deleteModel,
+    required this.downloadModel,
+    required this.modelInfoMap,
+    required this.modelsReady,
+    required this.selectModel,
+    super.key,
+  });
+
+  // final TranscriptBloc bloc;
+  final Map<LlmModel, ModelInfo> modelInfoMap;
+  final bool modelsReady;
+
+  /// Handler to delete the selected model.
+  final Function(LlmModel) deleteModel;
+
+  /// Handler to downloaded the selected model.
+  final Function(LlmModel) downloadModel;
+
+  /// Handler to change the selected model.
+  final Function(LlmModel) selectModel;
+
+  @override
+  Widget build(BuildContext context) {
+    return Padding(
+      padding: const EdgeInsets.all(8.0),
+      child: ListView(
+        // scrollDirection: Axis.horizontal,
+        children: <Widget>[
+          _modelSelectionTile(LlmModel.gemma4bCpu),
+          _modelSelectionTile(LlmModel.gemma4bGpu),
+          _modelSelectionTile(LlmModel.gemma8bCpu),
+          _modelSelectionTile(LlmModel.gemma8bGpu),
+        ],
+      ),
+    );
+  }
+
+  Widget _modelSelectionTile(LlmModel model) {
+    return ModelSelectionTile(
+      model,
+      ready: modelsReady,
+      modelInfo: modelInfoMap[model]!,
+      selectModel: () => selectModel(model),
+      delete: () => deleteModel(model),
+      download: () => downloadModel(model),
+    );
+  }
+}
+
+class ModelSelectionTile extends StatelessWidget {
+  const ModelSelectionTile(
+    this.model, {
+    required this.delete,
+    required this.download,
+    required this.modelInfo,
+    required this.ready,
+    required this.selectModel,
+    super.key,
+  });
+
+  final LlmModel model;
+  final ModelInfo modelInfo;
+
+  /// False until the initial state of models is fully loaded. Do not render
+  /// warnings until this is true.
+  final bool ready;
+
+  /// Handler to change the selected model to [model].
+  final VoidCallback selectModel;
+
+  /// Handler to downloaded [model].
+  final VoidCallback download;
+
+  /// Handler to delete [model].
+  final VoidCallback delete;
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      onTap: _handleTap,
+      child: Card(
+        child: ListTile(
+          title: Text(
+            model.displayName,
+            // style: const TextStyle(fontSize: 12),
+          ),
+          leading: switch (modelInfo.state) {
+            ModelState.downloaded =>
+              const Icon(Icons.check, color: Colors.green),
+            ModelState.downloading => const Icon(Icons.downloading),
+            ModelState.empty => SizedBox.fromSize(size: const Size.square(1)),
+          },
+          subtitle: switch (modelInfo.state) {
+            ModelState.downloaded => Text(
+                humanize(modelInfo.downloadedBytes!),
+                style: TextStyle(fontSize: 11, color: Colors.grey[600]!),
+              ),
+            ModelState.downloading =>
+              _DownloadingBar(downloadPercent: modelInfo.downloadPercent!),
+            ModelState.empty => ready && modelInfo.remoteLocation == null
+                ? const Text('Configure URL to download',
+                    style: TextStyle(color: Colors.red))
+                : Container(), // const Icon(Icons.download),
+          },
+          trailing: GestureDetector(
+            onTap: () => _launchModal(context),
+            child: switch (modelInfo.state) {
+              ModelState.downloaded => const Icon(Icons.delete),
+              ModelState.downloading =>
+                SizedBox.fromSize(size: const Size.square(1)),
+              ModelState.empty => modelInfo.remoteLocation == null
+                  ? SizedBox.fromSize(size: const Size.square(1))
+                  : const Icon(Icons.download),
+            },
+          ),
+        ),
+      ),
+    );
+  }
+
+  // Responds to taps anywhere on the `ModelSelectionTile` except for the
+  // trailing action icon.
+  void _handleTap() {
+    final VoidCallback? actionHandler = switch (modelInfo.state) {
+      ModelState.downloaded => selectModel,
+      ModelState.downloading => null,
+      ModelState.empty => null,
+    };
+    actionHandler?.call();
+  }
+
+  // Responds to taps on the trailing action icon, which should always either
+  // do nothing or launch a modal.
+  void _launchModal(BuildContext context) {
+    final VoidCallback? actionHandler = switch (modelInfo.state) {
+      ModelState.downloaded => delete,
+      ModelState.downloading => null,
+      ModelState.empty => download,
+    };
+    if (actionHandler == null) {
+      return;
+    }
+    final String title = switch (modelInfo.state) {
+      ModelState.downloaded => 'Delete',
+      ModelState.downloading => '',
+      ModelState.empty => 'Download',
+    };
+
+    final String? message = switch (modelInfo.state) {
+      ModelState.downloaded =>
+        'Would you like to delete this downloaded model?',
+      ModelState.downloading => null,
+      ModelState.empty => 'Would you like to download this model?',
+    };
+
+    showAlertDialog<bool>(
+      context: context,
+      title: title,
+      message: message,
+      actions: <AlertDialogAction<bool>>[
+        AlertDialogAction<bool>(
+          key: false,
+          label: 'Cancel',
+          isDefaultAction: true,
+          isDestructiveAction: modelInfo.state == ModelState.downloaded,
+        ),
+        AlertDialogAction<bool>(
+          key: true,
+          label: title,
+          isDefaultAction: true,
+          isDestructiveAction: modelInfo.state == ModelState.downloaded,
+        ),
+      ],
+    ).then((result) {
+      if (result == true) {
+        actionHandler();
+      }
+    });
+  }
+}
+
+class _DownloadingBar extends StatelessWidget {
+  const _DownloadingBar({required this.downloadPercent});
+
+  final int downloadPercent;
+
+  @override
+  Widget build(BuildContext context) {
+    return GFProgressBar(
+      percentage: (downloadPercent / 100).toDouble().clamp(0, 1.0),
+      lineHeight: 8,
+      backgroundColor: Colors.green[100]!,
+      progressBarColor: Colors.green[700]!,
+    );
+  }
+}
+
+final gigaByte = pow(2, 30);
+final megaByte = pow(2, 20);
+
+String humanize(int fileSize) {
+  if (fileSize > gigaByte) {
+    return '${(fileSize / gigaByte).roundTo(2)} GB';
+  } else if (fileSize > megaByte) {
+    return '${(fileSize / megaByte).roundTo(2)} MB';
+  }
+  return '$fileSize bytes';
+}
+
+extension RoundableDouble on double {
+  double roundTo(int decimalPlaces) =>
+      double.parse(toStringAsFixed(decimalPlaces));
+}

packages/mediapipe-task-genai/example/lib/model_storage/io_model_storage.dart

@@ -0,0 +1,85 @@
+import 'dart:async';
+import 'dart:io';
+
+import 'package:example/models/models.dart';
+import 'package:path_provider/path_provider.dart';
+import 'package:path/path.dart' as path;
+
+import 'model_storage_interface.dart';
+
+class ModelStorage extends ModelStorageInterface {
+  @override
+  int binarySize(String location) {
+    final file = File(location);
+    if (!file.existsSync()) {
+      throw Exception('Unexpectedly asked for binary size of non-existent '
+          'file at $location');
+    }
+    return file.lengthSync();
+  }
+
+  @override
+  Future<bool> downloadExists(String downloadLocation) =>
+      File(downloadLocation).exists();
+
+  @override
+  Future<String> urlToDownloadDestination(Uri location) async => path.join(
+        (await _getDownloadFolder()).absolute.path,
+        location.pathSegments.last,
+      );
+
+  Directory? _downloadFolder;
+  Future<Directory> _getDownloadFolder() async {
+    _downloadFolder ??= await getApplicationCacheDirectory();
+    return Future.value(_downloadFolder);
+  }
+
+  @override
+  Future<void> abort(String location) async {
+    if (!_downloadCache.containsKey(location)) {
+      throw Exception('Abort called for location $location, which is not the '
+          'site of an ongoing donwload.');
+    }
+    final file = File(location);
+    if (await file.exists()) {
+      await file.delete();
+    }
+    _downloadCache[location]!.close();
+    _downloadCache.remove(location);
+  }
+
+  @override
+  Future<void> close(String location) async {
+    if (!_downloadCache.containsKey(location)) {
+      throw Exception('Abort called for location $location, which is not the '
+          'site of an ongoing donwload.');
+    }
+    _downloadCache[location]!.close();
+    _downloadCache.remove(location);
+  }
+
+  final _downloadCache = <String, StreamSink<List<int>>>{};
+
+  @override
+  Future<StreamSink<List<int>>> create(String location) async {
+    final file = File(location);
+    if (await file.exists()) {
+      throw Exception('Attempted to download on top of existing file at '
+          '$location. Delete that file before proceeding.');
+    }
+    _downloadCache[location] = file.openWrite();
+    return _downloadCache[location]!;
+  }
+
+  @override
+  Future<void> delete(LlmModel model) async {
+    final path = pathFor(model);
+    if (path != null) {
+      clearPathCache(model);
+      final file = File(path);
+      if (await file.exists()) {
+        await file.delete();
+      }
+    }
+  }
+}

packages/mediapipe-task-genai/example/lib/model_storage/model_storage.dart

@@ -0,0 +1,5 @@
+export 'model_storage_interface.dart';
+
+export 'universal_model_storage.dart'
+    if (dart.library.html) 'web_model_storage.dart'
+    if (dart.library.io) 'io_model_storage.dart';

packages/mediapipe-task-genai/example/lib/model_storage/model_storage_interface.dart

@@ -0,0 +1,120 @@
+import 'dart:async';
+
+import 'package:example/models/models.dart';
+import 'package:logging/logging.dart';
+
+typedef ModelPaths = Map<LlmModel, String>;
+
+final _log = Logger('ModelLocationStorage');
+
+abstract class ModelStorageInterface {
+  Future<void> setInitialModelLocations(
+    ModelPaths initialModelLocations,
+  ) async {
+    for (final (model, location) in initialModelLocations.items) {
+      _log.finer('${model.name} :: $location');
+      if (location.isEmpty) continue;
+      final uri = Uri.parse(location);
+
+      late final String downloadDestination;
+      switch (uri.scheme.startsWith('http')) {
+        case (true):
+          {
+            downloadDestination = await urlToDownloadDestination(uri);
+            if (await downloadExists(downloadDestination)) {
+              setPathCache(model, downloadDestination);
+            }
+            setUriCache(model, uri);
+          }
+        case (false):
+          {
+            // If the location provided does not start with "http", it must be
+            // something immediately accessible to the current runtime.
+            downloadDestination = location;
+            if (await downloadExists(downloadDestination)) {
+              setPathCache(model, downloadDestination);
+            } else {
+              _log.warning(
+                'Bad specification. Model for ${model.name} not found '
+                'at at $location',
+              );
+            }
+          }
+      }
+    }
+  }
+
+  /// Deletes the file at the given location.
+  Future<void> delete(LlmModel model);
+
+  /// Opens the resources to save an [LlmModel] binary and returns a stream to
+  /// which bytes may be written.
+  Future<StreamSink<List<int>>> create(String location);
+
+  /// Marks a download initiated by [create] as successfully completed. Throws
+  /// an exception if no such download is in progress.
+  Future<void> close(String location);
+
+  /// Terminates a download and deletes all progress. Throws an exception if no
+  /// such download is in progress.
+  Future<void> abort(String location);
+
+  /// Determine to where in on-device storage this remote Url should be downloaded.
+  Future<String> urlToDownloadDestination(Uri location);
+
+  /// {@template downloadExists}
+  /// Returns true if the model at the given file is completely downloaded, or
+  /// false if it does not exist at all or is still downloading.
+  /// {@endtemplate}
+  Future<bool> downloadExists(String downloadLocation);
+
+  /// {@template binarySize}
+  /// Returns the size of the binary at the given on-device location. Throws an
+  /// exception if the file does not exist, so before calling this method,
+  /// verify that the model is downloaded with [downloadExists].
+  /// {@endtemplate}
+  int binarySize(String location);
+
+  /// Returns the on-disk location of a downloaded model.
+  String? pathFor(LlmModel model) => _pathCache[model];
+
+  void clearPathCache(LlmModel model) => _pathCache.remove(model);
+
+  /// Returns the remote location of a model.
+  Uri? urlFor(LlmModel model) => _urlCache[model];
+
+  /// On disk locations for the model. This could either have been supplied
+  /// at compile-time via environment variable, or at runtime due to a web url
+  /// location (also defined at compile-time) that was since been downloaded.
+  final _pathCache = <LlmModel, String>{};
+
+  /// Off-disk locations for models that could be downloaded to disk. Doing so
+  /// will creating an entry in [_pathCache] for where the downloaded model
+  /// resides on disk.
+  ///
+  /// This is stored (if known) even if the storage system believes the model is
+  /// already downloaded, because the user could need to delete and redownload
+  /// said model.
+  final _urlCache = <LlmModel, Uri>{};
+
+  void setUriCache(LlmModel model, Uri location) {
+    _log.fine('Registered remote ${model.name} location at $location');
+    _urlCache[model] = location;
+  }
+
+  void setPathCache(LlmModel model, String location) {
+    _log.fine(
+      'Detected downloaded binary for ${model.name} of size '
+      '${binarySize(location)} bytes',
+    );
+    _pathCache[model] = location;
+  }
+}
+
+extension ItemsMap<K, V> on Map<K, V> {
+  Iterable<(K, V)> get items sync* {
+    for (final K key in keys) {
+      yield (key, this[key] as V);
+    }
+  }
+}

packages/mediapipe-task-genai/example/lib/model_storage/universal_model_storage.dart

@@ -0,0 +1,31 @@
+import 'dart:async';
+
+import 'package:example/models/models.dart';
+
+import 'model_storage_interface.dart';
+
+class ModelStorage extends ModelStorageInterface {
+  @override
+  int binarySize(String location) => throw UnimplementedError();
+
+  @override
+  Future<bool> downloadExists(String downloadLocation) =>
+      throw UnimplementedError();
+
+  @override
+  Future<String> urlToDownloadDestination(Uri location) async =>
+      throw UnimplementedError();
+
+  @override
+  Future<void> abort(String location) => throw UnimplementedError();
+
+  @override
+  Future<void> close(String location) => throw UnimplementedError();
+
+  @override
+  Future<void> delete(LlmModel model) => throw UnimplementedError();
+
+  @override
+  Future<StreamSink<List<int>>> create(String location) =>
+      throw UnimplementedError();
+}

packages/mediapipe-task-genai/example/lib/models/chat_message.dart

@@ -0,0 +1,94 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:freezed_annotation/freezed_annotation.dart';
+import 'package:uuid/uuid.dart';
+
+part 'chat_message.freezed.dart';
+
+@Freezed()
+class ChatMessage with _$ChatMessage {
+  const ChatMessage._();
+  const factory ChatMessage({
+    required String id,
+    required String body,
+    required MessageOrigin origin,
+    required int cursorPosition,
+
+    /// Always true for a user's message, but only true for the LLM once it has
+    /// finished composing its reply.
+    required bool isComplete,
+  }) = _ChatMessage;
+
+  factory ChatMessage.origin(String body, MessageOrigin origin) =>
+      origin == MessageOrigin.user
+          ? ChatMessage.user(body)
+          : ChatMessage.llm(body);
+
+  factory ChatMessage.llm(String body, {int? cursorPosition}) => ChatMessage(
+        // Sometimes the LLM starts a response with multiple empty newlines
+        body: body,
+        origin: MessageOrigin.llm,
+        cursorPosition: cursorPosition ?? 0,
+        isComplete: false,
+        id: const Uuid().v4(),
+      );
+
+  factory ChatMessage.user(String body) => ChatMessage(
+        body: body,
+        origin: MessageOrigin.user,
+        cursorPosition: body.length,
+        isComplete: true,
+        id: const Uuid().v4(),
+      );
+
+  ChatMessage complete() {
+    assert(() {
+      if (origin.isUser) {
+        throw Exception(
+          'Only expected to complete messages from the LLM. '
+          'Did you call complete() on the wrong ChatMessage?',
+        );
+      }
+      return true;
+    }());
+    return copyWith(isComplete: true);
+  }
+
+  bool get displayingFullString => cursorPosition == body.length;
+
+  // String get displayString => body.substring(0, cursorPosition);
+  String get displayString => body;
+
+  ChatMessage advanceCursor() => copyWith(cursorPosition: cursorPosition + 1);
+}
+
+enum MessageOrigin {
+  user,
+  llm;
+
+  bool get isUser => switch (this) {
+        MessageOrigin.user => true,
+        MessageOrigin.llm => false,
+      };
+
+  bool get isLlm => switch (this) {
+        MessageOrigin.user => false,
+        MessageOrigin.llm => true,
+      };
+
+  String get transcriptName => switch (this) {
+        MessageOrigin.user => 'USER',
+        MessageOrigin.llm => 'LLM',
+      };
+
+  Alignment alignmentFromTextDirection(TextDirection textDirection) =>
+      switch (textDirection) {
+        TextDirection.ltr =>
+          isUser ? Alignment.centerRight : Alignment.centerLeft,
+        TextDirection.rtl =>
+          isUser ? Alignment.centerLeft : Alignment.centerRight,
+      };
+}

packages/mediapipe-task-genai/example/lib/models/chat_message.freezed.dart

@@ -0,0 +1,230 @@
+// coverage:ignore-file
+// GENERATED CODE - DO NOT MODIFY BY HAND
+// ignore_for_file: type=lint
+// ignore_for_file: unused_element, deprecated_member_use, deprecated_member_use_from_same_package, use_function_type_syntax_for_parameters, unnecessary_const, avoid_init_to_null, invalid_override_different_default_values_named, prefer_expression_function_bodies, annotate_overrides, invalid_annotation_target, unnecessary_question_mark
+
+part of 'chat_message.dart';
+
+// **************************************************************************
+// FreezedGenerator
+// **************************************************************************
+
+T _$identity<T>(T value) => value;
+
+final _privateConstructorUsedError = UnsupportedError(
+    'It seems like you constructed your class using `MyClass._()`. This constructor is only meant to be used by freezed and you are not supposed to need it nor use it.\nPlease check the documentation here for more information: https://github.com/rrousselGit/freezed#adding-getters-and-methods-to-our-models');
+
+/// @nodoc
+mixin _$ChatMessage {
+  String get id => throw _privateConstructorUsedError;
+  String get body => throw _privateConstructorUsedError;
+  MessageOrigin get origin => throw _privateConstructorUsedError;
+  int get cursorPosition => throw _privateConstructorUsedError;
+
+  /// Always true for a user's message, but only true for the LLM once it has
+  /// finished composing its reply.
+  bool get isComplete => throw _privateConstructorUsedError;
+
+  @JsonKey(ignore: true)
+  $ChatMessageCopyWith<ChatMessage> get copyWith =>
+      throw _privateConstructorUsedError;
+}
+
+/// @nodoc
+abstract class $ChatMessageCopyWith<$Res> {
+  factory $ChatMessageCopyWith(
+          ChatMessage value, $Res Function(ChatMessage) then) =
+      _$ChatMessageCopyWithImpl<$Res, ChatMessage>;
+  @useResult
+  $Res call(
+      {String id,
+      String body,
+      MessageOrigin origin,
+      int cursorPosition,
+      bool isComplete});
+}
+
+/// @nodoc
+class _$ChatMessageCopyWithImpl<$Res, $Val extends ChatMessage>
+    implements $ChatMessageCopyWith<$Res> {
+  _$ChatMessageCopyWithImpl(this._value, this._then);
+
+  // ignore: unused_field
+  final $Val _value;
+  // ignore: unused_field
+  final $Res Function($Val) _then;
+
+  @pragma('vm:prefer-inline')
+  @override
+  $Res call({
+    Object? id = null,
+    Object? body = null,
+    Object? origin = null,
+    Object? cursorPosition = null,
+    Object? isComplete = null,
+  }) {
+    return _then(_value.copyWith(
+      id: null == id
+          ? _value.id
+          : id // ignore: cast_nullable_to_non_nullable
+              as String,
+      body: null == body
+          ? _value.body
+          : body // ignore: cast_nullable_to_non_nullable
+              as String,
+      origin: null == origin
+          ? _value.origin
+          : origin // ignore: cast_nullable_to_non_nullable
+              as MessageOrigin,
+      cursorPosition: null == cursorPosition
+          ? _value.cursorPosition
+          : cursorPosition // ignore: cast_nullable_to_non_nullable
+              as int,
+      isComplete: null == isComplete
+          ? _value.isComplete
+          : isComplete // ignore: cast_nullable_to_non_nullable
+              as bool,
+    ) as $Val);
+  }
+}
+
+/// @nodoc
+abstract class _$$ChatMessageImplCopyWith<$Res>
+    implements $ChatMessageCopyWith<$Res> {
+  factory _$$ChatMessageImplCopyWith(
+          _$ChatMessageImpl value, $Res Function(_$ChatMessageImpl) then) =
+      __$$ChatMessageImplCopyWithImpl<$Res>;
+  @override
+  @useResult
+  $Res call(
+      {String id,
+      String body,
+      MessageOrigin origin,
+      int cursorPosition,
+      bool isComplete});
+}
+
+/// @nodoc
+class __$$ChatMessageImplCopyWithImpl<$Res>
+    extends _$ChatMessageCopyWithImpl<$Res, _$ChatMessageImpl>
+    implements _$$ChatMessageImplCopyWith<$Res> {
+  __$$ChatMessageImplCopyWithImpl(
+      _$ChatMessageImpl _value, $Res Function(_$ChatMessageImpl) _then)
+      : super(_value, _then);
+
+  @pragma('vm:prefer-inline')
+  @override
+  $Res call({
+    Object? id = null,
+    Object? body = null,
+    Object? origin = null,
+    Object? cursorPosition = null,
+    Object? isComplete = null,
+  }) {
+    return _then(_$ChatMessageImpl(
+      id: null == id
+          ? _value.id
+          : id // ignore: cast_nullable_to_non_nullable
+              as String,
+      body: null == body
+          ? _value.body
+          : body // ignore: cast_nullable_to_non_nullable
+              as String,
+      origin: null == origin
+          ? _value.origin
+          : origin // ignore: cast_nullable_to_non_nullable
+              as MessageOrigin,
+      cursorPosition: null == cursorPosition
+          ? _value.cursorPosition
+          : cursorPosition // ignore: cast_nullable_to_non_nullable
+              as int,
+      isComplete: null == isComplete
+          ? _value.isComplete
+          : isComplete // ignore: cast_nullable_to_non_nullable
+              as bool,
+    ));
+  }
+}
+
+/// @nodoc
+
+class _$ChatMessageImpl extends _ChatMessage {
+  const _$ChatMessageImpl(
+      {required this.id,
+      required this.body,
+      required this.origin,
+      required this.cursorPosition,
+      required this.isComplete})
+      : super._();
+
+  @override
+  final String id;
+  @override
+  final String body;
+  @override
+  final MessageOrigin origin;
+  @override
+  final int cursorPosition;
+
+  /// Always true for a user's message, but only true for the LLM once it has
+  /// finished composing its reply.
+  @override
+  final bool isComplete;
+
+  @override
+  String toString() {
+    return 'ChatMessage(id: $id, body: $body, origin: $origin, cursorPosition: $cursorPosition, isComplete: $isComplete)';
+  }
+
+  @override
+  bool operator ==(Object other) {
+    return identical(this, other) ||
+        (other.runtimeType == runtimeType &&
+            other is _$ChatMessageImpl &&
+            (identical(other.id, id) || other.id == id) &&
+            (identical(other.body, body) || other.body == body) &&
+            (identical(other.origin, origin) || other.origin == origin) &&
+            (identical(other.cursorPosition, cursorPosition) ||
+                other.cursorPosition == cursorPosition) &&
+            (identical(other.isComplete, isComplete) ||
+                other.isComplete == isComplete));
+  }
+
+  @override
+  int get hashCode =>
+      Object.hash(runtimeType, id, body, origin, cursorPosition, isComplete);
+
+  @JsonKey(ignore: true)
+  @override
+  @pragma('vm:prefer-inline')
+  _$$ChatMessageImplCopyWith<_$ChatMessageImpl> get copyWith =>
+      __$$ChatMessageImplCopyWithImpl<_$ChatMessageImpl>(this, _$identity);
+}
+
+abstract class _ChatMessage extends ChatMessage {
+  const factory _ChatMessage(
+      {required final String id,
+      required final String body,
+      required final MessageOrigin origin,
+      required final int cursorPosition,
+      required final bool isComplete}) = _$ChatMessageImpl;
+  const _ChatMessage._() : super._();
+
+  @override
+  String get id;
+  @override
+  String get body;
+  @override
+  MessageOrigin get origin;
+  @override
+  int get cursorPosition;
+  @override
+
+  /// Always true for a user's message, but only true for the LLM once it has
+  /// finished composing its reply.
+  bool get isComplete;
+  @override
+  @JsonKey(ignore: true)
+  _$$ChatMessageImplCopyWith<_$ChatMessageImpl> get copyWith =>
+      throw _privateConstructorUsedError;
+}

packages/mediapipe-task-genai/example/lib/models/llm_model.dart

@@ -0,0 +1,76 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:freezed_annotation/freezed_annotation.dart';
+
+part 'llm_model.freezed.dart';
+
+enum Hardware { cpu, gpu }
+
+enum LlmModel {
+  gemma4bCpu,
+  gemma4bGpu,
+  gemma8bCpu,
+  gemma8bGpu;
+
+  Hardware get hardware => switch (this) {
+        gemma4bCpu => Hardware.cpu,
+        gemma4bGpu => Hardware.gpu,
+        gemma8bCpu => Hardware.cpu,
+        gemma8bGpu => Hardware.gpu,
+      };
+
+  String get dartDefine => switch (this) {
+        gemma4bCpu => const String.fromEnvironment('GEMMA_4B_CPU_URI'),
+        gemma4bGpu => const String.fromEnvironment('GEMMA_4B_GPU_URI'),
+        gemma8bCpu => const String.fromEnvironment('GEMMA_8B_CPU_URI'),
+        gemma8bGpu => const String.fromEnvironment('GEMMA_8B_GPU_URI'),
+      };
+
+  String get environmentVariableUriName => switch (this) {
+        gemma4bCpu => 'GEMMA_4B_CPU_URI',
+        gemma4bGpu => 'GEMMA_4B_GPU_URI',
+        gemma8bCpu => 'GEMMA_8B_CPU_URI',
+        gemma8bGpu => 'GEMMA_8B_GPU_URI',
+      };
+
+  String get displayName => switch (this) {
+        gemma4bCpu => 'Gemma 4b CPU',
+        gemma4bGpu => 'Gemma 4b GPU',
+        gemma8bCpu => 'Gemma 8b CPU',
+        gemma8bGpu => 'Gemma 8b GPU',
+      };
+}
+
+@Freezed()
+class ModelInfo with _$ModelInfo {
+  const ModelInfo._();
+  const factory ModelInfo({
+    /// Size of the on-disk location of this model. A null value here either
+    /// means that the model is currently downloading or completely missing.
+    int? downloadedBytes,
+
+    /// 0-100 if a model is being downloaded. A null value here means no
+    /// download is in progress for the given model.
+    int? downloadPercent,
+
+    /// Location of the model if it is available on disk.
+    String? path,
+
+    /// Location from which the model can be downloaded if it is not already
+    /// available.
+    Uri? remoteLocation,
+  }) = _ModelInfo;
+
+  ModelState get state {
+    if (downloadedBytes != null) {
+      return ModelState.downloaded;
+    } else if (downloadPercent != null) {
+      return ModelState.downloading;
+    }
+    return ModelState.empty;
+  }
+}
+
+enum ModelState { downloaded, downloading, empty }

packages/mediapipe-task-genai/example/lib/models/llm_model.freezed.dart

@@ -0,0 +1,232 @@
+// coverage:ignore-file
+// GENERATED CODE - DO NOT MODIFY BY HAND
+// ignore_for_file: type=lint
+// ignore_for_file: unused_element, deprecated_member_use, deprecated_member_use_from_same_package, use_function_type_syntax_for_parameters, unnecessary_const, avoid_init_to_null, invalid_override_different_default_values_named, prefer_expression_function_bodies, annotate_overrides, invalid_annotation_target, unnecessary_question_mark
+
+part of 'llm_model.dart';
+
+// **************************************************************************
+// FreezedGenerator
+// **************************************************************************
+
+T _$identity<T>(T value) => value;
+
+final _privateConstructorUsedError = UnsupportedError(
+    'It seems like you constructed your class using `MyClass._()`. This constructor is only meant to be used by freezed and you are not supposed to need it nor use it.\nPlease check the documentation here for more information: https://github.com/rrousselGit/freezed#adding-getters-and-methods-to-our-models');
+
+/// @nodoc
+mixin _$ModelInfo {
+  /// Size of the on-disk location of this model. A null value here either
+  /// means that the model is currently downloading or completely missing.
+  int? get downloadedBytes => throw _privateConstructorUsedError;
+
+  /// 0-100 if a model is being downloaded. A null value here means no
+  /// download is in progress for the given model.
+  int? get downloadPercent => throw _privateConstructorUsedError;
+
+  /// Location of the model if it is available on disk.
+  String? get path => throw _privateConstructorUsedError;
+
+  /// Location from which the model can be downloaded if it is not already
+  /// available.
+  Uri? get remoteLocation => throw _privateConstructorUsedError;
+
+  @JsonKey(ignore: true)
+  $ModelInfoCopyWith<ModelInfo> get copyWith =>
+      throw _privateConstructorUsedError;
+}
+
+/// @nodoc
+abstract class $ModelInfoCopyWith<$Res> {
+  factory $ModelInfoCopyWith(ModelInfo value, $Res Function(ModelInfo) then) =
+      _$ModelInfoCopyWithImpl<$Res, ModelInfo>;
+  @useResult
+  $Res call(
+      {int? downloadedBytes,
+      int? downloadPercent,
+      String? path,
+      Uri? remoteLocation});
+}
+
+/// @nodoc
+class _$ModelInfoCopyWithImpl<$Res, $Val extends ModelInfo>
+    implements $ModelInfoCopyWith<$Res> {
+  _$ModelInfoCopyWithImpl(this._value, this._then);
+
+  // ignore: unused_field
+  final $Val _value;
+  // ignore: unused_field
+  final $Res Function($Val) _then;
+
+  @pragma('vm:prefer-inline')
+  @override
+  $Res call({
+    Object? downloadedBytes = freezed,
+    Object? downloadPercent = freezed,
+    Object? path = freezed,
+    Object? remoteLocation = freezed,
+  }) {
+    return _then(_value.copyWith(
+      downloadedBytes: freezed == downloadedBytes
+          ? _value.downloadedBytes
+          : downloadedBytes // ignore: cast_nullable_to_non_nullable
+              as int?,
+      downloadPercent: freezed == downloadPercent
+          ? _value.downloadPercent
+          : downloadPercent // ignore: cast_nullable_to_non_nullable
+              as int?,
+      path: freezed == path
+          ? _value.path
+          : path // ignore: cast_nullable_to_non_nullable
+              as String?,
+      remoteLocation: freezed == remoteLocation
+          ? _value.remoteLocation
+          : remoteLocation // ignore: cast_nullable_to_non_nullable
+              as Uri?,
+    ) as $Val);
+  }
+}
+
+/// @nodoc
+abstract class _$$ModelInfoImplCopyWith<$Res>
+    implements $ModelInfoCopyWith<$Res> {
+  factory _$$ModelInfoImplCopyWith(
+          _$ModelInfoImpl value, $Res Function(_$ModelInfoImpl) then) =
+      __$$ModelInfoImplCopyWithImpl<$Res>;
+  @override
+  @useResult
+  $Res call(
+      {int? downloadedBytes,
+      int? downloadPercent,
+      String? path,
+      Uri? remoteLocation});
+}
+
+/// @nodoc
+class __$$ModelInfoImplCopyWithImpl<$Res>
+    extends _$ModelInfoCopyWithImpl<$Res, _$ModelInfoImpl>
+    implements _$$ModelInfoImplCopyWith<$Res> {
+  __$$ModelInfoImplCopyWithImpl(
+      _$ModelInfoImpl _value, $Res Function(_$ModelInfoImpl) _then)
+      : super(_value, _then);
+
+  @pragma('vm:prefer-inline')
+  @override
+  $Res call({
+    Object? downloadedBytes = freezed,
+    Object? downloadPercent = freezed,
+    Object? path = freezed,
+    Object? remoteLocation = freezed,
+  }) {
+    return _then(_$ModelInfoImpl(
+      downloadedBytes: freezed == downloadedBytes
+          ? _value.downloadedBytes
+          : downloadedBytes // ignore: cast_nullable_to_non_nullable
+              as int?,
+      downloadPercent: freezed == downloadPercent
+          ? _value.downloadPercent
+          : downloadPercent // ignore: cast_nullable_to_non_nullable
+              as int?,
+      path: freezed == path
+          ? _value.path
+          : path // ignore: cast_nullable_to_non_nullable
+              as String?,
+      remoteLocation: freezed == remoteLocation
+          ? _value.remoteLocation
+          : remoteLocation // ignore: cast_nullable_to_non_nullable
+              as Uri?,
+    ));
+  }
+}
+
+/// @nodoc
+
+class _$ModelInfoImpl extends _ModelInfo {
+  const _$ModelInfoImpl(
+      {this.downloadedBytes,
+      this.downloadPercent,
+      this.path,
+      this.remoteLocation})
+      : super._();
+
+  /// Size of the on-disk location of this model. A null value here either
+  /// means that the model is currently downloading or completely missing.
+  @override
+  final int? downloadedBytes;
+
+  /// 0-100 if a model is being downloaded. A null value here means no
+  /// download is in progress for the given model.
+  @override
+  final int? downloadPercent;
+
+  /// Location of the model if it is available on disk.
+  @override
+  final String? path;
+
+  /// Location from which the model can be downloaded if it is not already
+  /// available.
+  @override
+  final Uri? remoteLocation;
+
+  @override
+  String toString() {
+    return 'ModelInfo(downloadedBytes: $downloadedBytes, downloadPercent: $downloadPercent, path: $path, remoteLocation: $remoteLocation)';
+  }
+
+  @override
+  bool operator ==(Object other) {
+    return identical(this, other) ||
+        (other.runtimeType == runtimeType &&
+            other is _$ModelInfoImpl &&
+            (identical(other.downloadedBytes, downloadedBytes) ||
+                other.downloadedBytes == downloadedBytes) &&
+            (identical(other.downloadPercent, downloadPercent) ||
+                other.downloadPercent == downloadPercent) &&
+            (identical(other.path, path) || other.path == path) &&
+            (identical(other.remoteLocation, remoteLocation) ||
+                other.remoteLocation == remoteLocation));
+  }
+
+  @override
+  int get hashCode => Object.hash(
+      runtimeType, downloadedBytes, downloadPercent, path, remoteLocation);
+
+  @JsonKey(ignore: true)
+  @override
+  @pragma('vm:prefer-inline')
+  _$$ModelInfoImplCopyWith<_$ModelInfoImpl> get copyWith =>
+      __$$ModelInfoImplCopyWithImpl<_$ModelInfoImpl>(this, _$identity);
+}
+
+abstract class _ModelInfo extends ModelInfo {
+  const factory _ModelInfo(
+      {final int? downloadedBytes,
+      final int? downloadPercent,
+      final String? path,
+      final Uri? remoteLocation}) = _$ModelInfoImpl;
+  const _ModelInfo._() : super._();
+
+  @override
+
+  /// Size of the on-disk location of this model. A null value here either
+  /// means that the model is currently downloading or completely missing.
+  int? get downloadedBytes;
+  @override
+
+  /// 0-100 if a model is being downloaded. A null value here means no
+  /// download is in progress for the given model.
+  int? get downloadPercent;
+  @override
+
+  /// Location of the model if it is available on disk.
+  String? get path;
+  @override
+
+  /// Location from which the model can be downloaded if it is not already
+  /// available.
+  Uri? get remoteLocation;
+  @override
+  @JsonKey(ignore: true)
+  _$$ModelInfoImplCopyWith<_$ModelInfoImpl> get copyWith =>
+      throw _privateConstructorUsedError;
+}

packages/mediapipe-task-genai/example/lib/models/models.dart

@@ -0,0 +1,2 @@
+export 'chat_message.dart';
+export 'llm_model.dart';

packages/mediapipe-task-genai/example/lib/widgets/chat_input.dart

@@ -0,0 +1,40 @@
+import 'package:flutter/material.dart';
+
+class ChatInput extends StatelessWidget {
+  const ChatInput({
+    required this.submit,
+    required this.controller,
+    required this.isLlmTyping,
+    super.key,
+  });
+
+  final TextEditingController controller;
+
+  final void Function(String) submit;
+
+  /// Prevents submitting new messages when true.
+  final bool isLlmTyping;
+
+  @override
+  Widget build(BuildContext context) {
+    return Row(
+      children: [
+        Expanded(child: TextField(controller: controller)),
+        ValueListenableBuilder(
+          valueListenable: controller,
+          builder: (context, value, child) {
+            return IconButton(
+              icon: const Icon(Icons.send),
+              onPressed: controller.text != '' && !isLlmTyping
+                  ? () {
+                      submit(controller.text);
+                      controller.clear();
+                    }
+                  : null,
+            );
+          },
+        ),
+      ],
+    );
+  }
+}

packages/mediapipe-task-genai/example/lib/widgets/chat_screen.dart

@@ -0,0 +1,165 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:chat_bubbles/chat_bubbles.dart';
+import 'package:example/bloc.dart';
+import 'package:example/models/models.dart';
+import 'package:example/widgets/widgets.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+
+class ChatScreen extends StatefulWidget {
+  const ChatScreen(this.bloc, {required this.model, super.key});
+
+  final TranscriptBloc bloc;
+  final LlmModel model;
+
+  @override
+  State<ChatScreen> createState() => _ChatScreenState();
+}
+
+class _ChatScreenState extends State<ChatScreen> {
+  final TextEditingController _controller = TextEditingController();
+
+  static const initialText = 'Hello, world!';
+
+  @override
+  void initState() {
+    if (widget.bloc.state.transcript[widget.model]!.isEmpty) {
+      _controller.text = initialText;
+    }
+    super.initState();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final bloc = widget.bloc;
+    return BlocBuilder<TranscriptBloc, TranscriptState>(
+      bloc: bloc,
+      builder: (context, state) {
+        return Scaffold(
+          appBar: AppBar(title: Text(widget.model.displayName)),
+          endDrawer: Drawer(
+            child: Padding(
+              padding: const EdgeInsets.all(12),
+              child: InferenceConfigurationPanel(
+                topK: state.topK,
+                temp: state.temperature,
+                maxTokens: state.maxTokens,
+                updateTopK: (val) => bloc.add(UpdateTopK(val)),
+                updateTemp: (val) => bloc.add(UpdateTemperature(val)),
+                updateMaxTokens: (val) => bloc.add(UpdateMaxTokens(val)),
+              ),
+            ),
+          ),
+          body: SafeArea(
+            child: Padding(
+              padding: const EdgeInsets.all(8.0),
+              child: Column(
+                children: <Widget>[
+                  Expanded(
+                    child: KeyboardHider(
+                      child: ChatTranscript(state.transcript[widget.model]!),
+                    ),
+                  ),
+                  ChatInput(
+                    controller: _controller,
+                    isLlmTyping: state.isLlmTyping,
+                    submit: (String value) {
+                      bloc.add(
+                        AddMessage(ChatMessage.user(value), widget.model),
+                      );
+                    },
+                  ),
+                ],
+              ),
+            ),
+          ),
+        );
+      },
+    );
+  }
+}
+
+class ChatTranscript extends StatefulWidget {
+  const ChatTranscript(
+    this.transcript, {
+    super.key,
+  });
+
+  final List<ChatMessage> transcript;
+
+  @override
+  State<ChatTranscript> createState() => _ChatTranscriptState();
+}
+
+class _ChatTranscriptState extends State<ChatTranscript> {
+  @override
+  Widget build(BuildContext context) {
+    return LayoutBuilder(
+      builder: (context, constraints) {
+        return ListView.builder(
+          reverse: true,
+          itemCount: widget.transcript.length,
+          itemBuilder: (context, index) {
+            final messageIndex = widget.transcript.length - index - 1;
+            final message = widget.transcript[messageIndex];
+
+            return Padding(
+              padding: const EdgeInsets.only(top: 6),
+              child: message.displayString != ''
+                  ? ChatMessageBubble(
+                      message: message,
+                      width: constraints.maxWidth * 0.8,
+                      key: ValueKey('message-${message.id}'),
+                    )
+                  : const TypingIndicator(
+                      showIndicator: true,
+                    ),
+            );
+          },
+        );
+      },
+    );
+  }
+}
+
+class ChatMessageBubble extends StatelessWidget {
+  const ChatMessageBubble({
+    required this.message,
+    required this.width,
+    super.key,
+  });
+
+  final ChatMessage message;
+  final double width;
+
+  // Colors.blue[400]
+  static const llmBgColor = Color(0xFF42A5F5);
+
+  // Colors.orange[400]
+  static const userBgColor = Color(0xFFFFA726);
+
+  @override
+  Widget build(BuildContext context) {
+    return Row(
+      children: [
+        if (message.origin.isUser) Flexible(flex: 2, child: Container()),
+        Flexible(
+          flex: 6,
+          child: BubbleSpecialThree(
+            text: message.displayString,
+            color: message.origin.isUser ? userBgColor : llmBgColor,
+            isSender: message.origin.isUser,
+            textStyle: const TextStyle(color: Colors.white),
+            sent: message.isComplete,
+            delivered: message.isComplete,
+            seen: message.isComplete,
+          ),
+        ),
+        if (message.origin.isLlm) Flexible(flex: 2, child: Container()),
+      ],
+    );
+  }
+}

packages/mediapipe-task-genai/example/lib/widgets/configuration_panel.dart

@@ -0,0 +1,111 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+
+/// Contains sliders for each configuration option for option passed to the
+/// inference engine.
+class InferenceConfigurationPanel extends StatelessWidget {
+  const InferenceConfigurationPanel({
+    required this.topK,
+    required this.temp,
+    required this.maxTokens,
+    required this.updateTopK,
+    required this.updateTemp,
+    required this.updateMaxTokens,
+    super.key,
+  });
+
+  /// Top K number of tokens to be sampled from for each decoding step.
+  final int topK;
+
+  /// Handler to update [topK].
+  final void Function(int) updateTopK;
+
+  /// Context size window for the LLM.
+  final int maxTokens;
+
+  /// Handler to update [maxTokens].
+  final void Function(int) updateMaxTokens;
+
+  /// Randomness when decoding the next token.
+  final double temp;
+
+  /// Handler to update [temp].
+  final void Function(double) updateTemp;
+
+  @override
+  Widget build(BuildContext context) {
+    return ListView(
+      children: <Widget>[
+        Text('Top K', style: Theme.of(context).textTheme.bodyLarge),
+        Text('Number of tokens to be sampled from for each decoding step.',
+            style: Theme.of(context).textTheme.bodySmall),
+        Slider(
+          value: topK.toDouble(),
+          min: 1,
+          max: 100,
+          divisions: 100,
+          onChanged: (newTopK) => updateTopK(newTopK.toInt()),
+        ),
+        Text(
+          topK.toString(),
+          style: Theme.of(context)
+              .textTheme
+              .bodySmall!
+              .copyWith(color: Colors.grey),
+        ),
+        const Divider(),
+        Text('Temperature', style: Theme.of(context).textTheme.bodyLarge),
+        Text('Randomness when decoding the next token.',
+            style: Theme.of(context).textTheme.bodySmall),
+        Slider(
+          value: temp,
+          min: 0,
+          max: 1,
+          onChanged: updateTemp,
+        ),
+        Text(
+          temp.roundTo(3).toString(),
+          style: Theme.of(context)
+              .textTheme
+              .bodySmall!
+              .copyWith(color: Colors.grey),
+        ),
+        const Divider(),
+        Text('Max Tokens', style: Theme.of(context).textTheme.bodyLarge),
+        Text(
+            'Maximum context window for the LLM. Larger windows can tax '
+            'certain devices.',
+            style: Theme.of(context).textTheme.bodySmall),
+        Slider(
+          value: maxTokens.toDouble(),
+          min: 512,
+          max: 8192,
+          onChanged: (newMaxTokens) => updateMaxTokens(newMaxTokens.toInt()),
+        ),
+        Text(
+          maxTokens.toString(),
+          style: Theme.of(context)
+              .textTheme
+              .bodySmall!
+              .copyWith(color: Colors.grey),
+        ),
+        const Divider(),
+        GestureDetector(
+          onTap: () => Navigator.of(context).pop(),
+          child: Text(
+            'Close',
+            style: Theme.of(context).textTheme.headlineMedium,
+          ),
+        ),
+      ],
+    );
+  }
+}
+
+extension on double {
+  double roundTo(int decimalPlaces) =>
+      double.parse(toStringAsFixed(decimalPlaces));
+}

packages/mediapipe-task-genai/example/lib/widgets/keyboard_hider.dart

@@ -0,0 +1,24 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/services.dart';
+import 'package:flutter/widgets.dart';
+
+class KeyboardHider extends StatelessWidget {
+  const KeyboardHider({required this.child, super.key});
+
+  final Widget? child;
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      onTap: () {
+        // Not sure why this one isn't working.
+        // FocusScope.of(context).unfocus();
+        SystemChannels.textInput.invokeMethod('TextInput.hide');
+      },
+      child: child,
+    );
+  }
+}