在Android开发中利用MediaRecorder实现一个录音功能

public class MediaRecorderActivity extends BaseActivity { private Button start_tv; private ListView listView; //线程操作 private ExecutorService mExecutorService; //录音API private MediaRecorder mMediaRecorder; //录音开始时间与结束时间 private long startTime, endTime; //录音所保存的文件 private File mAudioFile; //文件列表数据 private List<FileBean> dataList; //录音文件数据列表适配器 private AudioAdapter mAudioAdapter; //录音文件保存位置 private String mFilePath = Environment.getExternalStorageDirectory().getAbsolutePath() + "/audio/"; //当前是否正在播放 private volatile boolean isPlaying; //播放音频文件API private MediaPlayer mediaPlayer; //使用Handler更新UI线程 private Handler mHandler = new Handler() {  @Override  public void handleMessage(Message msg) {   super.handleMessage(msg);   switch (msg.what) {    case Constant.RECORD_SUCCESS:     //录音成功，展示数据     if (null == mAudioAdapter) {      mAudioAdapter = new AudioAdapter(MediaRecorderActivity.this, dataList, R.layout.file_item_layout);     }     listView.setAdapter(mAudioAdapter);     break;    //录音失败    case Constant.RECORD_FAIL:     showToastMsg(getString(R.string.record_fail));     break;    //录音时间太短    case Constant.RECORD_TOO_SHORT:     showToastMsg(getString(R.string.time_too_short));     break;    case Constant.PLAY_COMPLETION:     showToastMsg(getString(R.string.play_over));     break;    case Constant.PLAY_ERROR:     showToastMsg(getString(R.string.play_error));     break;   }  } }; @Override protected void setWindowView() {  setContentView(R.layout.activity_record);  //录音及播放要使用单线程操作  mExecutorService = Executors.newSingleThreadExecutor();  dataList = new ArrayList<>(); } @Override protected void initViews() {  this.start_tv = (Button) findViewById(R.id.start_tv);  this.listView = (ListView) findViewById(R.id.listview); } @Override protected void initEvents() {  //类似微信等应用按住说话进行录音，所以用OnTouch事件  this.start_tv.setOnTouchListener(new View.OnTouchListener() {   @Override   public boolean onTouch(View view, MotionEvent motionEvent) {    switch (motionEvent.getAction()) {     //按下操作     case MotionEvent.ACTION_DOWN:      //安卓6.0以上录音相应权限处理      if (Build.VERSION.SDK_INT > 22) {       permissionForM();      } else {       startRecord();      }      break;     //松开操作     case MotionEvent.ACTION_CANCEL:     case MotionEvent.ACTION_UP:      stopRecord();      break;    }    //对OnTouch事件做了处理，返回true    return true;   }  });  //点击播放对应的录音文件  this.listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {   @Override   public void onItemClick(AdapterView<&#63;> adapterView, View view, int i, long l) {    //使用MediaPlayer播放声音文件    startPlay(dataList.get(i).getFile());   }  }); }  private void startRecord() {  start_tv.setText(R.string.stop_by_up);  start_tv.setBackgroundResource(R.drawable.bg_gray_round);  //异步任务执行录音操作  mExecutorService.submit(new Runnable() {   @Override   public void run() {    //播放前释放资源    releaseRecorder();    //执行录音操作    recordOperation();   }  }); }  private void recordFail() {  mAudioFile = null;  mHandler.sendEmptyMessage(Constant.RECORD_FAIL); }  private void recordOperation() {  //创建MediaRecorder对象  mMediaRecorder = new MediaRecorder();  //创建录音文件,.m4a为MPEG-4音频标准的文件的扩展名  mAudioFile = new File(mFilePath + System.currentTimeMillis() + ".m4a");  //创建父文件夹  mAudioFile.getParentFile().mkdirs();  try {   //创建文件   mAudioFile.createNewFile();   //配置mMediaRecorder相应参数   //从麦克风采集声音数据   mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);   //设置保存文件格式为MP4   mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);   //设置采样频率,44100是所有安卓设备都支持的频率,频率越高，音质越好，当然文件越大   mMediaRecorder.setAudioSamplingRate(44100);   //设置声音数据编码格式,音频通用格式是AAC   mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);   //设置编码频率   mMediaRecorder.setAudioEncodingBitRate(96000);   //设置录音保存的文件   mMediaRecorder.setOutputFile(mAudioFile.getAbsolutePath());   //开始录音   mMediaRecorder.prepare();   mMediaRecorder.start();   //记录开始录音时间   startTime = System.currentTimeMillis();  } catch (Exception e) {   e.printStackTrace();   recordFail();  } }  private void stopRecord() {  start_tv.setText(R.string.speak_by_press);  start_tv.setBackgroundResource(R.drawable.bg_white_round);  //停止录音  mMediaRecorder.stop();  //记录停止时间  endTime = System.currentTimeMillis();  //录音时间处理，比如只有大于2秒的录音才算成功  int time = (int) ((endTime - startTime) / 1000);  if (time >= 3) {   //录音成功,添加数据   FileBean bean = new FileBean();   bean.setFile(mAudioFile);   bean.setFileLength(time);   dataList.add(bean);   //录音成功,发Message   mHandler.sendEmptyMessage(Constant.RECORD_SUCCESS);  } else {   mAudioFile = null;   mHandler.sendEmptyMessage(Constant.RECORD_TOO_SHORT);  }  //录音完成释放资源  releaseRecorder(); }  private void releaseRecorder() {  if (null != mMediaRecorder) {   mMediaRecorder.release();   mMediaRecorder = null;  } } @Override public void onClick(View view) { } @Override protected void onDestroy() {  super.onDestroy();  //页面销毁，线程要关闭  mExecutorService.shutdownNow(); }   private void permissionForM() {  if (ContextCompat.checkSelfPermission(this,    Manifest.permission.RECORD_AUDIO) != PackageManager.PERMISSION_GRANTED || ContextCompat.checkSelfPermission(this,    Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {   ActivityCompat.requestPermissions(this,     new String[]{Manifest.permission.RECORD_AUDIO, Manifest.permission.WRITE_EXTERNAL_STORAGE},     Constant.PERMISSIONS_REQUEST_FOR_AUDIO);  } else {   startRecord();  } } @Override public void onRequestPermissionsResult(int requestCode,           @NonNull String[] permissions, @NonNull int[] grantResults) {  if (requestCode == Constant.PERMISSIONS_REQUEST_FOR_AUDIO) {   if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {    startRecord();   }   return;  }  super.onRequestPermissionsResult(requestCode, permissions, grantResults); }  private void playAudio(final File mFile) {  if (null != mFile && !isPlaying) {   isPlaying = true;   mExecutorService.submit(new Runnable() {    @Override    public void run() {     startPlay(mFile);    }   });  } }  private void startPlay(File mFile) {  try {   //初始化播放器   mediaPlayer = new MediaPlayer();   //设置播放音频数据文件   mediaPlayer.setDataSource(mFile.getAbsolutePath());   //设置播放监听事件   mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {    @Override    public void onCompletion(MediaPlayer mediaPlayer) {     //播放完成     playEndOrFail(true);    }   });   //播放发生错误监听事件   mediaPlayer.setOnErrorListener(new MediaPlayer.OnErrorListener() {    @Override    public boolean onError(MediaPlayer mediaPlayer, int i, int i1) {     playEndOrFail(false);     return true;    }   });   //播放器音量配置   mediaPlayer.setVolume(1, 1);   //是否循环播放   mediaPlayer.setLooping(false);   //准备及播放   mediaPlayer.prepare();   mediaPlayer.start();  } catch (IOException e) {   e.printStackTrace();   //播放失败正理   playEndOrFail(false);  } }  private void playEndOrFail(boolean isEnd) {  isPlaying = false;  if (isEnd) {   mHandler.sendEmptyMessage(Constant.PLAY_COMPLETION);  } else {   mHandler.sendEmptyMessage(Constant.PLAY_ERROR);  }  if (null != mediaPlayer) {   mediaPlayer.setOnCompletionListener(null);   mediaPlayer.setOnErrorListener(null);   mediaPlayer.stop();   mediaPlayer.reset();   mediaPlayer.release();   mediaPlayer = null;  } }}