如何使用Exoplayer为视频下载和添加字幕

implementation 'com.google.android.exoplayer:exoplayer-core:2.X.X'
implementation 'com.google.android.exoplayer:exoplayer-ui:2.X.X'

SimpleExoPlayer player = new SimpleExoPlayer.Builder(context).build();

MediaItem mediaItem = MediaItem.fromUri(videoUrl);
player.setMediaItem(mediaItem);

MediaItem.Subtitle subtitle = MediaItem.Subtitle(Uri.parse(subtitleUrl), MimeTypes.APPLICATION_SUBRIP, "en");
MediaItem mediaItem = MediaItem.fromUri(videoUrl).setSubtitles(Collections.singletonList(subtitle));
player.setMediaItem(mediaItem);

player.prepare();

player.play();

player.addListener(new Player.EventListener() {
    @Override
    public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
        // 处理播放器状态变化事件
    }
});