public void stop(View view) {
    try {
      isStopped = true;
      exRecorder.stop();
      exRecorder.release();

      stopBtn.setEnabled(false);
      playBtn.setEnabled(true);
      convertchipmunk.setEnabled(true);
      Toast.makeText(getApplicationContext(), "Stop recording...", Toast.LENGTH_SHORT).show();
    } catch (IllegalStateException e) {
      e.printStackTrace();
    } catch (RuntimeException e) {
      e.printStackTrace();
    }
  }
  public void start(View view) {
    try {
      isStopped = false;
      isChipmunkVoice = false;
      exRecorder.prepare();
      exRecorder.start();
    } catch (IllegalStateException e) {
      e.printStackTrace();
    } catch (Exception e) {
      e.printStackTrace();
    }

    startBtn.setEnabled(false);
    stopBtn.setEnabled(true);
    convertchipmunk.setEnabled(false);
    Toast.makeText(getApplicationContext(), "Start recording...", Toast.LENGTH_SHORT).show();
  }
 private void initializeRecorder() {
   exRecorder = ExtAudioRecorder.getInstanse(false);
   exRecorder.setOutputFile(outputFile.getAbsolutePath());
 }