com.tomtom.sdk:tts-engine-android/com.tomtom.sdk.tts.android/AndroidTextToSpeechEngine

AndroidTextToSpeechEngine

class AndroidTextToSpeechEngine : TextToSpeechEngine

TextToSpeechEngine implementation based on Android's TextToSpeech. An AndroidTextToSpeechEngine instance can only be used once it has completed its initialization. Implement the OnEngineReadyListener to be notified of the completion of the initialization. When you are done using the AndroidTextToSpeechEngine instance, call the close() method to release resources.

Example usage:

val ttsEngine = AndroidTextToSpeechEngine(context)
ttsEngine.addOnEngineReadyListener(object : OnEngineReadyListener {
    override fun onReady() {
        // TTS engine is ready for use
    }
    override fun onError(error: TextToSpeechEngineError) {
        // Handle TTS engine initialization error
    }
})

// Voices API usage (once TTS engine is initialized):
val voicesResult = ttsEngine.getVoices()
if (voicesResult.isSuccess()) {
    val availableVoices = voicesResult.value()
    val voicesInCurrentLanguage = availableVoices.filter {
        it.locale.language == currentLanguage.language // filter voices by current language
    }
    val selectedVoice = voicesInCurrentLanguage.first() // select preferred voice depending on the use case
    val setVoiceResult = ttsEngine.setVoice(selectedVoice)
    if (setVoiceResult.isFailure()) {
        // Handle setting voice error
    }
} else {
    // Handle getting voices error
}

ttsEngine.close() // Release the resources when done

Important: This is a Public Preview API. It may be changed or removed at any time.

Constructors

AndroidTextToSpeechEngine

constructor(context: Context, language: Locale = LocaleProvider.preferredLocale())

Types

Companion

object Companion

Properties

supportedPhoneticAlphabets

open override val supportedPhoneticAlphabets: List<String>

Supported phonetic alphabets. This engine supports only IPA_PHONETIC_ALPHABET.

Functions

addOnEngineReadyListener

open override fun addOnEngineReadyListener(listener: OnEngineReadyListener)

Sets a listener to report on the readiness of the TextToSpeechEngine.

changeLanguage

open override fun changeLanguage(language: Locale)

Changes the language that is used to synthesize audio messages.

open override fun close()

currentLanguage

open override fun currentLanguage(): Locale?

Returns the current language used to synthesize audio messages.

getVoices

fun getVoices(): Result<Set<Voice>, TextToSpeechEngineError>

Retrieves a set of available text to speech voices. The retrieved set can be filtered by voice properties (e.g. language, network usage) when needed.

isLanguageAvailable

open override fun isLanguageAvailable(language: Locale): Boolean

Checks whether the specified language as represented by the Locale is available.

playAudioMessage

open override fun playAudioMessage(audioMessage: AudioMessage, playbackListener: MessagePlaybackListener)

Synthesizes an audio message. If another audioMessage is currently being processed this one will be added to the queue. If there is already another AudioMessages in the queue it will be flushed and replaced by this one.

playTaggedMessage

open override fun playTaggedMessage(taggedMessage: TaggedMessage, playbackListener: MessagePlaybackListener)

Synthesizes a tagged message. TaggedMessage is parsed into MessageType.Ssml format prior to being synthesized. PhoneticAlphabetNotSupportedError is thrown if an unsupported phonetic alphabet is used.

removeOnEngineReadyListener

open override fun removeOnEngineReadyListener(listener: OnEngineReadyListener)

Removes the listener that reports on the readiness of the TextToSpeechEngine.

setVoice

fun setVoice(voice: Voice): Result<Unit, TextToSpeechEngineError>

Sets the text to speech voice. Use getVoices to retrieve a collection of available voices.

stopMessagePlayback

open override fun stopMessagePlayback()

Stops synthesis of current AudioMessage and discards all messages in the queue.