How to enable subtitles on dash stream?

ExoPlayer 2.9.1 I run exoPlayer on AndroidTV with leanback support.

my configuration

ExoPlayerFactory.newSimpleInstance(
            context,
            DefaultRenderersFactory(context),
            trackSelector,
            DefaultLoadControl(),
            defaultDrmSessionManager
        )

and I switch tracks using below method:

    fun setTrack(model: FormatUiModel) {
        val newParams = trackSelector.buildUponParameters()

        when (model.formatType) {
            FormatUiModel.Type.VIDEO -> {
                newParams.setMaxVideoBitrate(model.format.bitrate)
                newParams.setMaxVideoSize(model.format.width, model.format.height)
            }
            FormatUiModel.Type.AUDIO -> {
                newParams.setPreferredAudioLanguage(model.format.language)
            }
            FormatUiModel.Type.TEXT -> {
                newParams.setRendererDisabled(C.TRACK_TYPE_VIDEO, false)
                newParams.setPreferredTextLanguage(model.format.language)
            }
        }
        trackSelector.parameters = newParams.build()
    }

it works fine for video and audio. But subtitles/text are not displaying but I can see that text track is selected.

All available tracks:

com.tv.uat D/ExoPlayerAdapter: getFormatsFromTrackGroups 0, 0 Format(video=1001000, null, video/mp4, video/avc, avc1.640028, 1001000, null, [1024, 576, 25.0], [-1, -1])
com.tv.uat D/ExoPlayerAdapter: getFormatsFromTrackGroups 0, 1 Format(video=2001000, null, video/mp4, video/avc, avc1.640028, 2001000, null, [1280, 720, 25.0], [-1, -1])
com.tv.uat D/ExoPlayerAdapter: getFormatsFromTrackGroups 0, 2 Format(video=5001000, null, video/mp4, video/avc, avc1.640028, 5001000, null, [1920, 1080, 25.0], [-1, -1])
com.tv.uat D/ExoPlayerAdapter: getFormatsFromTrackGroups 0, 0 Format(audio_eng=128000, null, audio/mp4, audio/mp4a-latm, mp4a.40.2, 128000, en, [-1, -1, -1.0], [2, 48000])
com.tv.uat D/ExoPlayerAdapter: getFormatsFromTrackGroups 1, 0 Format(audio_lav=128000, null, audio/mp4, audio/mp4a-latm, mp4a.40.2, 128000, lv, [-1, -1, -1.0], [2, 48000])
com.tv.uat D/ExoPlayerAdapter: getFormatsFromTrackGroups 2, 0 Format(audio_lit=128000, null, audio/mp4, audio/mp4a-latm, mp4a.40.2, 128000, lt, [-1, -1, -1.0], [2, 48000])
com.tv.uat D/ExoPlayerAdapter: getFormatsFromTrackGroups 0, 0 Format(textstream_est=1000, null, application/mp4, application/ttml+xml, stpp, 1000, et, [-1, -1, -1.0], [-1, -1])
com.tv.uat D/ExoPlayerAdapter: getFormatsFromTrackGroups 1, 0 Format(textstream_lav=1000, null, application/mp4, application/ttml+xml, stpp, 1000, lv, [-1, -1, -1.0], [-1, -1])
com.tv.uat D/ExoPlayerAdapter: getFormatsFromTrackGroups 2, 0 Format(textstream_rus=1000, null, application/mp4, application/ttml+xml, stpp, 1000, ru, [-1, -1, -1.0], [-1, -1])

Can someone shows how to implement selecting text tracks? Or point me to right doc.

[ojw28]

Are you using our PlayerView UI component?

It takes care of rendering the subtitles if you’re using it. If you’re not using it then you need to add something as a text output to the player (player.addTextOutput), which will receive the subtitles. You’ll then need to render them. You can use SubtitleView for this, if you don’t want to use the full PlayerView. You can add a SubtitleView` as a text output directly on the player.

[luna-vulpo]

nop. I use leanback for android tv. Very similar as in this example: https://github.com/googlearchive/leanback-showcase

I will falow your advide. thx.