I'm making a media player, but I just can't seem to add subtitles. I immediately retrieve all the subtitles and pass them to MediaItem. When the user selects new subtitles, I retrieve them using trackSelectionParameters, where the ID is the link. The player plays them and saves them. And SubtitleView should display them, but I don't see any text. Right now, I have something like this:

    
            var currentCues by remember { mutableStateOf<List<Cue>>(emptyList()) }
            var currentTracks by remember { mutableStateOf(Tracks.EMPTY) }

            LaunchedEffect(selectedSource) {
                currentCues = emptyList()

                val subtitleConfigs = playerData.subtitles.map { subtitle ->
                    MediaItem.SubtitleConfiguration.Builder(Uri.parse(subtitle.src))
                        .setMimeType(MimeTypes.TEXT_VTT)
                        .setId(subtitle.src)
                        .setLabel(subtitle.label)
                        .build()
                }

                val mediaItem = MediaItem.Builder()
                    .setUri(selectedSource)
                    .setSubtitleConfigurations(subtitleConfigs)
                    .build()

                setItem(mediaItem)
            }

            LaunchedEffect(selectedSubtitles, currentTracks) {
                val trackSelectionParameters = exoPlayer.trackSelectionParameters.buildUpon()

                if (selectedSubtitles == null) {
                    trackSelectionParameters.setTrackTypeDisabled(C.TRACK_TYPE_TEXT, true)
                    trackSelectionParameters.clearOverridesOfType(C.TRACK_TYPE_TEXT)
                } else {
                    trackSelectionParameters.setTrackTypeDisabled(C.TRACK_TYPE_TEXT, false)

                    currentTracks.groups.find { trackGroup ->
                        trackGroup.type == C.TRACK_TYPE_TEXT &&
                                trackGroup.mediaTrackGroup.getFormat(0).id == selectedSubtitles
                    }?.let { textTrackGroup ->
                        trackSelectionParameters.setOverrideForType(
                            TrackSelectionOverride(textTrackGroup.mediaTrackGroup, 0)
                        )
                    }
                }

                exoPlayer.trackSelectionParameters = trackSelectionParameters.build()
            }

            DisposableEffect(exoPlayer) {
                val listener = object : Player.Listener {
// ...
                    override fun onCues(cueGroup: CueGroup) {
                        currentCues = cueGroup.cues
                    }

                    override fun onTracksChanged(tracks: Tracks) {
                        currentTracks = tracks
                    }
                }
                exoPlayer.addListener(listener)
                onDispose {
                    exoPlayer.removeListener(listener)
                }
            }

            Box(
                modifier = Modifier
                    .fillMaxSize()
                    .focusable()
                    .onKeyEvent { // ... }
            ) {
                key(selectedSource) {
                    PlayerSurface(
                        player = exoPlayer,
                        surfaceType = SURFACE_TYPE_TEXTURE_VIEW,
                        modifier = Modifier
                            .fillMaxSize()
                            .resizeWithContentScale(
                                contentScale = ContentScale.Fit,
                                sourceSizeDp = null
                            )
                    )
                }

                AndroidView(
                    factory = { ctx ->
                        SubtitleView(ctx).apply {
                        }
                    },
                    update = { view ->
                        view.setCues(currentCues)
                    },
                    modifier = Modifier
                        .fillMaxSize()
                        .padding(bottom = if (isControlsVisible) 100.dp else 24.dp)
                )

At first, I was reloading all the videos whenever the user selected new ones. Now I load them all at once and just switch between them. But they still don't show up.