<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />

public class TestActivity extends BaseActivity {
    private ActivityChatBinding testBinding;
    private MediaRecorder mediaRecorder;
    private boolean isRecorded;

    @Override
    public void initView() {
        testBinding = ActivityTestBinding.inflate(getLayoutInflater());
        setContentView(testBinding.getRoot());
        initMsgAndSth();
        checkPermission();
    }

    private void initMsgAndSth(){
        String record_Home = this.getFilesDir()+"/Sample";  //聲明存儲路徑，用絕對路徑什么都可以
        //btnTalk就是個Button
        testBinding.btnTalk.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (isRecorded)
                    stopRecordAudio();
                else
                    startRecordAudio(record_Home);
            }
        });
    }

    private void stopRecordAudio() {
        //有的5.0機型上MediaRecorder.stop會報錯，這里建議抓取一下異常
        if(mediaRecorder !=null){
            try {
                mediaRecorder.stop();//停止錄音
                mediaRecorder.release();//釋放資源
                mediaRecorder =null;
            }catch (Exception exception){
                mediaRecorder.reset();//重置
                mediaRecorder.release();//釋放資源
                mediaRecorder =null;
            }
            Toast.makeText(this,"停止錄音",Toast.LENGTH_SHORT).show();
        }
    }

    private void startRecordAudio(String path) {
        //文件夾一定要先創建，不然報錯的bug信息中是找不到這里的
        File audioFile = new File(path);
        if (!audioFile.exists()) {
            audioFile.mkdirs();
        } else if (!audioFile.isDirectory()) {
            audioFile.delete();
            audioFile.mkdirs();
        }
        File file = new File(path + "Sample.amr");
        if(!file.exists()){
            try {
                file.createNewFile();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        if(mediaRecorder == null){
            mediaRecorder = new MediaRecorder();
            mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);//設置麥克風
            /*
             * 設置保存輸出文件的格式：THREE_GPP/MPEG-4/RAW_AMR/Default THREE_GPP(3gp格式
             * ，H263視頻/ARM音頻編碼)、MPEG-4、RAW_AMR(只支持音頻且音頻編碼要求為AMR_NB)
             */
            mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.AMR_NB);

            mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);//設置音頻文件編碼格式
            mediaRecorder.setOutputFile(path+"Sample.amr");
        }
        try {
            mediaRecorder.prepare();  //start之前要先prepare
            mediaRecorder.start();
            isRecorded = true;
            Toast.makeText(this,"開始錄音",Toast.LENGTH_SHORT).show();
        } catch (IllegalStateException el){
            el.printStackTrace();
        } catch (RuntimeException e){
            e.printStackTrace();
        } catch (Exception e){
            e.printStackTrace();
        }
    }

    /**
     * 簡單的權限申請邏輯
     */
    private void checkPermission() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            String[] permissions = new String[]{Manifest.permission.RECORD_AUDIO,Manifest.permission.WRITE_EXTERNAL_STORAGE};
            for (String permission : permissions) {
                if (ContextCompat.checkSelfPermission(this, permission) != PackageManager.PERMISSION_GRANTED) {
                    ActivityCompat.requestPermissions(this, permissions, 200);
                    return;
                }
            }
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[]
            grantResults) {
        super.onRequestPermissionsResult(requestCode,permissions,grantResults);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && requestCode == 200) {
            for (int i = 0; i < permissions.length; i++) {
                if (grantResults[i] != PackageManager.PERMISSION_GRANTED) {
                    Intent intent = new Intent();
                    intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
                    Uri uri = Uri.fromParts("package", getPackageName(), null);
                    intent.setData(uri);
                    startActivityForResult(intent, 200);
                    return;
                }
            }
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (resultCode == RESULT_OK && requestCode == 200) {
            checkPermission();
        }
    }
}

android:requestLegacyExternalStorage="true"

RuntimeException: setAudioSource failed