我想向后播放音频。我找到了方法https://developer.android.com/reference/androidx/media2/common/sessionplayer?hl=ko#setplaybackspeed（浮动）在这里。
所以我写代码

import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;

import androidx.media2.common.FileMediaItem;
import androidx.media2.common.MediaMetadata;
import androidx.media2.player.MediaPlayer;

import android.os.ParcelFileDescriptor;
import android.util.Log;
import java.io.File;
import java.util.concurrent.Executor;

...
 public void audioPlayer(String path, String fileName){
        try{
            File file = new File(path);
            if(file.exists()){
                Log.d("CalendarModule","File Exists");
                mp = new MediaPlayer(this.getReactApplicationContext());
                ParcelFileDescriptor pfd = ParcelFileDescriptor.open(file,ParcelFileDescriptor.MODE_READ_ONLY);
                FileMediaItem fmi = new FileMediaItem.Builder(pfd).build();
                MediaMetadata mm = new MediaMetadata.Builder().putString(MediaMetadata.METADATA_KEY_TITLE,path).build();
                fmi.setMetadata(mm);
                mp.setMediaItem(fmi);
                mp.prepare().addListener(new Runnable() {
                    @Override
                    public void run() {
                        mp.play();
                    }
                }, new Executor() {
                    @Override
                    public void execute(Runnable command) {

                    }
                });
            }
            else{
                Log.d("CalendarModule","File NOT");
            }
        }
        catch (Exception e){
            e.printStackTrace();
        }
    }

...
但我什么也听不见。如何播放音频文件？代码能反向播放音频吗？