Before Compose I had an Android TTS manager that tracked the progress of large amounts of text. And I used a SeekBar to mark the reading progress. Now I want to change the SeekBar for a Slider to mark the reading progress, but I can’t get it to work. I don’t know how to connect the TTS reading progress with a Slider.

This is the code of my TTS Manager;

class TtsManagerCompose(
    context: Context,
    text: String,
    splitRegex: String,
    private val mProgressListener: (Int, Int) -> Unit

)  : OnInitListener {
    private val mTexts: Array<String>
    private val mTts: TextToSpeech
    private var mTextProgress = 0
    private var mIsPlaying = false

    init {
        mTexts = text.split(splitRegex.toRegex()).dropLastWhile { it.isEmpty() }.toTypedArray()
        mTts = TextToSpeech(context, this)
        mTts.setOnUtteranceProgressListener(object : UtteranceProgressListener() {
            override fun onDone(utteranceId: String) {
                if (!mIsPlaying || mTextProgress == mTexts.size) return
                ++mTextProgress
                updateProgress(mTextProgress, mTexts.size)
                speakText()
            }

            override fun onStart(utteranceId: String) {}

            @Deprecated("Deprecated in Java")
            override fun onError(utteranceId: String) {
                //onError(utteranceId);
            }
        })
    }

    private fun speakText() {
        if (mTextProgress >= mTexts.size) return
        val bundle = Bundle()
        bundle.putInt(TextToSpeech.Engine.KEY_PARAM_STREAM, AudioManager.STREAM_MUSIC)
        mTts.speak(mTexts[mTextProgress], TextToSpeech.QUEUE_FLUSH, bundle, "TTS_ID")
    }

    fun start() {
        mIsPlaying = true
        speakText()
    }

    fun pause() {
        mIsPlaying = false
        mTts.stop()
        updateProgress(mTextProgress, mTexts.size)
    }

    fun resume() {
        mIsPlaying = false
        mTts.stop()
        start()
        updateProgress(mTextProgress, mTexts.size)
    }

    fun stop() {
        mIsPlaying = false
        mTts.stop()
        mTextProgress = 0
        updateProgress(mTextProgress, mTexts.size)
    }

    private fun updateProgress(current: Int, max: Int) {
        mProgressListener.invoke(current, max)
    }

    fun changeProgress(progress: Int) {
        mTextProgress = progress
        if (!mIsPlaying) return
        pause()
        start()
    }

    override fun onInit(status: Int) {
        if (status == TextToSpeech.SUCCESS) {
            val locSpanish = Locale("spa", "ESP")
            val result = mTts.setLanguage(locSpanish)
            if (result == TextToSpeech.LANG_MISSING_DATA || result == TextToSpeech.LANG_NOT_SUPPORTED) {
                return
            }
            changeProgress(1)
        }
    }

    fun close() {
        mTts.stop()
        mTts.shutdown()
    }
}

This is the code for the screen:

private var mTtsManager: TtsManagerCompose? = null

@ExperimentalMaterial3Api
@Composable
fun TextToSpeechScreen(text:String,) {
    var readText by remember { mutableStateOf(false) }
    Column(modifier = Modifier.padding(24.dp)) {
        isSpeaking = false
        SliderMinimalExample()

        if(readText){
            readText(text = text)
        }
        
        Button(onClick = {
            readText=true
        }) {
            Image(
                painterResource(id = R.drawable.ic_play),
                contentDescription ="Play",
                modifier = Modifier.size(20.dp))
        }

        Button(onClick = {
            mTtsManager?.stop()
            readText=false
        }) {
            Image(
                painterResource(id = R.drawable.ic_baseline_stop_circle_24),
                contentDescription ="Stop",
                modifier = Modifier.size(20.dp)) }
    }
    
    //TODO: Buttons for Pause / Resume ...
}

And this is the code for read the text:

@Composable
private fun readText(text:String) {
    mTtsManager = TtsManagerCompose(
        LocalContext.current, text,
        Constants.SEPARADOR,
    ) { current: Int, max: Int ->
//        seekBar!!.progress = current
//        seekBar!!.max = max
    }
    mTtsManager!!.start()
}