如何在android的Exo播放器中更改视频、音频和字幕曲目

// 导入ExoPlayer库
implementation 'com.google.android.exoplayer:exoplayer-core:2.x.x'

// 初始化ExoPlayer
SimpleExoPlayer player = new SimpleExoPlayer.Builder(context).build();

// 创建媒体源
MediaItem mediaItem1 = MediaItem.fromUri(videoUrl1);
MediaItem mediaItem2 = MediaItem.fromUri(videoUrl2);
MediaItem subtitleItem = MediaItem.fromUri(subtitleUrl);

MediaSource videoSource1 = new DefaultMediaSource.Factory(dataSourceFactory)
                            .createMediaSource(mediaItem1);
MediaSource videoSource2 = new DefaultMediaSource.Factory(dataSourceFactory)
                            .createMediaSource(mediaItem2);
MediaSource subtitleSource = new DefaultMediaSource.Factory(dataSourceFactory)
                                .createMediaSource(subtitleItem);

// 切换曲目
player.setMediaSource(videoSource1);
player.prepare();

// 在需要切换时
player.setMediaSource(videoSource2);
player.prepare();

// 切换字幕
player.addTextOutput(subtitleSource);

// 控制播放器
player.play();
player.pause();
player.stop();