我在emulator（pixel 3a api 30）上测试录音应用程序时遇到问题
下面是我在youtube教程中搜索到的java代码。在视频中可以正常测试。说到我，当我按下停止录音按钮时，它一直在崩溃。

//Request Runtime Permission
        if (!checkPermissionFromDevice())
            requestPermission();

        //Init view
        pl_btn = (Button)findViewById(R.id.play_btn);
        rcrd_btn = (Button)findViewById(R.id.record_button);
        stp_rcrd_btn = (Button)findViewById(R.id.stop_record_btn);
        ps_btn = (Button)findViewById(R.id.pause_btn);

        //From Android M, need request Run-time permission

            rcrd_btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {

                    if (checkPermissionFromDevice()) {

                        pathSave = Environment.getExternalStorageDirectory()
                                .getAbsolutePath() + "/"
                                + UUID.randomUUID().toString() + "audio_record.3gp";
                        setupMediaRecorder();
                        try {
                            mediaRecorder.prepare();
                            mediaRecorder.start();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }

                        pl_btn.setEnabled(false);
                        ps_btn.setEnabled(false);
                        rcrd_btn.setEnabled(false);
                        stp_rcrd_btn.setEnabled(true);

                        Toast.makeText(recording_and_play_test.this, "Recording...", Toast.LENGTH_SHORT).show();
                    } else {
                        requestPermission();
                    }
                }
            });

            stp_rcrd_btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    mediaRecorder.stop();
                    stp_rcrd_btn.setEnabled(false);
                    pl_btn.setEnabled(true);
                    rcrd_btn.setEnabled(true);
                    ps_btn.setEnabled(false);
                }
            });

            pl_btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    ps_btn.setEnabled(true);
                    stp_rcrd_btn.setEnabled(false);
                    rcrd_btn.setEnabled(false);

                    mediaPlayer = new MediaPlayer();
                    try {
                        mediaPlayer.setDataSource(pathSave);
                        mediaPlayer.prepare();
                    }catch (IOException e){
                        e.printStackTrace();
                    }

                    mediaPlayer.start();
                    Toast.makeText(recording_and_play_test.this, "Playing...", Toast.LENGTH_SHORT).show();
                }
            });

            ps_btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    stp_rcrd_btn.setEnabled(false);
                    rcrd_btn.setEnabled(true);
                    pl_btn.setEnabled(true);
                    ps_btn.setEnabled(false);

                    if (mediaPlayer != null){
                        mediaPlayer.stop();
                        mediaPlayer.release();
                        setupMediaRecorder();

                    }
                }
            });

    }

    private void setupMediaRecorder() {
        mediaRecorder = new MediaRecorder();
        mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
        mediaRecorder.setAudioEncoder(MediaRecorder.OutputFormat.AMR_NB);
        mediaRecorder.setOutputFile(pathSave);
    }

    private void requestPermission() {
        ActivityCompat.requestPermissions(this, new String[]{
                Manifest.permission.WRITE_EXTERNAL_STORAGE,
                Manifest.permission.RECORD_AUDIO
        },REQUEST_PERMISSION_CODE);
    }

下面是活动的样子

当我在执行录制功能时按下停止录制按钮时，应用程序崩溃并重新启动。
以下是构建日志中的内容

E/MediaRecorder: stop called in an invalid state: 4
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.adrsingingscope, PID: 7309
    java.lang.IllegalStateException
        at android.media.MediaRecorder.stop(Native Method)
        at com.example.adrsingingscope.recording_and_play_test$2.onClick(recording_and_play_test.java:88)
        at android.view.View.performClick(View.java:7448)
        at android.view.View.performClickInternal(View.java:7425)
        at android.view.View.access$3600(View.java:810)
        at android.view.View$PerformClick.run(View.java:28305)
        at android.os.Handler.handleCallback(Handler.java:938)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:223)
        at android.app.ActivityThread.main(ActivityThread.java:7656)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)