选择声音以在播放声音时添加播放器列表
首先添加声音，将播放器列表设置好 第二次也不错 但是第三或第四次出现致命异常
请提供任何建议。
E/AndroidRuntime: FATAL EXCEPTION: pool-2-thread-1
Process: com.example.demo123, PID: 16704
java.lang.NullPointerException: Attempt to read from field 'java.lang.Object androidx.core.util.Pair.second' on a null object reference
at androidx.media2.player.MediaPlayer$10.onExecute(MediaPlayer.java:1195)
at androidx.media2.player.MediaPlayer$PendingFuture.execute(MediaPlayer.java:571)
at androidx.media2.player.MediaPlayer.executePendingFutures(MediaPlayer.java:3032)
at androidx.media2.player.MediaPlayer.handleCallComplete(MediaPlayer.java:3024)
at androidx.media2.player.MediaPlayer$Mp2Callback.onCallCompleted(MediaPlayer.java:3247)
at androidx.media2.player.exoplayer.ExoPlayerMediaPlayer2Impl$Task$1.notify(ExoPlayerMediaPlayer2Impl.java:941)
at androidx.media2.player.exoplayer.ExoPlayerMediaPlayer2Impl$2.run(ExoPlayerMediaPlayer2Impl.java:204)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
at java.lang.Thread.run(Thread.java:919)