Alan Flutter Framework¶

Available on: Android iOS

The Alan Flutter plugin helps you to integrate your voice experience and Alan Studio script into your Flutter app.

Note

The alan_voice package version 3.0.0 supports null safety. If your app does not use null safety yet, upgrade the Dart version to 2.12 or higher or use a previous version of the alan_voice package.

Integrating with Alan¶

To integrate a Flutter app with Alan:

In the pubspec.yaml file of your Flutter project, add the Alan voice dependency:
pubspec.yaml¶
```
dependencies:
  flutter:
    sdk: flutter
  alan_voice: 2.4.0
```
Open the main.dart file and at the top of it, add the alan_voice package dependency:
main.dart¶
```
import 'package:alan_voice/alan_voice.dart';
```

In the _MyHomePageState class, add the method for initializing the Alan button:

main.dart¶

class _MyHomePageState extends State<MyHomePage> {
  _MyHomePageState() {
    /// Initializing Alan with sample project id
    AlanVoice.addButton(
      "",
      buttonAlign: AlanVoice.BUTTON_ALIGN_LEFT);
 }

In Alan Studio, go to Integrations, copy the value from the Alan SDK Key field and insert this value in the quotes.

main.dart¶

class _MyHomePageState extends State<MyHomePage> {
  _MyHomePageState() {
    /// Initializing Alan with sample project id
    AlanVoice.addButton(
      "314203787ccd9370974f1bf6b6929c1b2e956eca572e1d8b807a3e2338fdd0dc/prod",
      buttonAlign: AlanVoice.BUTTON_ALIGN_LEFT);
  }

That’s it. Now you can run the app, tap the Alan button and start interacting with Alan.

Specifying the Alan button parameters¶

You can specify the following parameters for the Alan button added to your app:

Name	Type	Description
`projectId`	string	The Alan SDK key for a project in Alan Studio.
`authJson`	JSON object	The authentication or configuration data to be sent to the voice script. For details, see authData.
`buttonAlign`	Int	The Alan button position in the app. Use one of the two constants: `BUTTON_ALIGN_LEFT` or `BUTTON_ALIGN_RIGHT`.

Using client API methods¶

You can use the following client API methods in your app:

setVisualState()
callProjectApi()
playText()
playCommand()
activate()
deactivate()
isActive()
getWakewordEnabled()
setWakewordEnabled()

setVisualState()¶

Use the setVisualState() method to inform the voice assistant about the app’s visual context. For details, see setVisualState().

Client app¶

_MyHomePageState() {
  void _setVisualState() {
    /// Providing any params with json
    var visualState = jsonEncode({"data":"your data"});
    AlanVoice.setVisualState(visualState);
  }
}

callProjectApi()¶

Use the callProjectApi() method to send data from the client app to the voice script and trigger activities without voice commands. For details, see callProjectApi().

Voice script¶

projectAPI.setClientData = function(p, param, callback) {
  console.log(param);
};

Client app¶

_MyHomePageState() {
  void _callProjectApi() {
    /// Providing any params with json
    var params = jsonEncode({"data":"your data"});
    AlanVoice.callProjectApi("script::setClientData", params);
  }
}

playText()¶

Use the playText() method to play specific text in the client app. For details, see playText().

Client app¶

_MyHomePageState() {
  /// Playing any text message
  void _playText() {
    /// Providing text as string param
    AlanVoice.playText("Hi");
  }
}

playCommand()¶

Use the playCommand() method to execute a specific command in the client app. For details, see playCommand().

Client app¶

_MyHomePageState() {
  /// Executing a command locally
  void _playCommand() {
    /// Providing any params with json
    var command = jsonEncode({"action":"openSomePage"});
    AlanVoice.playCommand(command);
  }
}

activate()¶

Use the activate() method to activate the Alan button programmatically. For details, see activate().

Client app¶

_MyHomePageState() {
  /// Activating the Alan button programmatically
  void _activate() {
    AlanVoice.activate();
  }
}

deactivate()¶

Use the deactivate() method to deactivate the Alan button programmatically. For details, see deactivate().

Client app¶

_MyHomePageState() {
  /// Deactivating the Alan button programmatically
  void _deactivate() {
    AlanVoice.deactivate();
  }
}

isActive()¶

Use the isActive() method to check the Alan button state: active or not. For details, see isActive().

Client app¶

void _checkIsActive() async {
  var isActive = await AlanVoice.isActive();
  if (isActive) {
    _showDialog("Active");
  } else {
    _showDialog("NOT active");
  }
}

getWakewordEnabled()¶

Use the getWakewordEnabled() method to check the state of the wake word for the Alan button. For details, see getWakewordEnabled().

Client app¶

var enabled = await AlanVoice.getWakewordEnabled();

setWakewordEnabled()¶

Use the setWakewordEnabled() method to enable or disable the wake word for the Alan button. For details, see setWakewordEnabled().

Client app¶

AlanVoice.setWakewordEnabled(enabled);

Using handlers¶

You can use the following Alan handlers in your app:

onCommand handler
onButtonState handler
onEvent handler

onCommand handler¶

Use the onCommand handler to handle commands sent from the voice script. For details, see onCommand handler.

Client app¶

_MyHomePageState() {
  /// Handle commands from Alan Studio
  AlanVoice.onCommand.add((command) {
    debugPrint("got new command ${command.toString()}");
  });
}

onButtonState handler¶

Use the onButtonState handler to capture and handle the Alan button state changes. For details, see onButtonState handler.

Client app¶

_MyHomePageState() {
  /// Handle button state
  AlanVoice.onButtonState.add((state) {
    debugPrint("got new button state ${state.name}");
  });
}

onEvent handler¶

Use the onEvent handler to capture and handle events emitted by Alan: get user’s utterances, voice assistant responses and so on. For details, see onEvent handler.

Client app¶

_MyHomePageState() {
  /// Handle events
  AlanVoice.onEvent.add((event) {
    debugPrint("got new event ${event.data.toString()}");
  });
}

Switching between logging levels¶

By default, Alan does not log its system events such as change of the Alan button state to the IDE console. If you want to see messages from Alan, switch to the all logging level:

main.dart¶

AlanVoice.setLogLevel("all");

To disable logs, either remove the line above or switch to the none logging level:

main.dart¶

AlanVoice.setLogLevel("none");

Troubleshooting¶

To troubleshoot problems you may have with your Flutter app, check the solutions below:

The minimum possible Android SDK version required by the Alan SDK is 21. If the version in your project is lower, you may encounter the following error: AndroidManifest.xml Error: uses-sdk:minSdkVersion 16 cannot be smaller than version 21 declared in library [:alan_voice]. Open the ./android/app/build.gradle file, under defaultConfig, locate minSdkVersion and change the version to 21.
Starting from version 3.0.0, the alan_voice package supports null safety. If you encounter the following error: Cannot run with sound null safety because dependencies don't support null safety, upgrade to the latest package version.
(If running the app on an emulator) All virtual microphone options must be enabled. On the emulator settings bar, click More (…) > Microphone and make sure all toggles are set to the On position.

What’s next?¶

Example apps

Find and explore examples of voice-enabled apps on the Alan AI GitHub repository.

View on GitHub