public void setRecordButtonVisible(boolean isVisible) {
   if (isVisible) {
     mRecord.setVisibility(VISIBLE);
   } else {
     mRecord.setVisibility(INVISIBLE);
   }
 }
 public void notifyStopRecord() {
   mPlayPause.update();
   mStop.update();
   if (mRecord != null) mRecord.update();
 }
 public void notifyStop() {
   // Send state change signal to all buttons
   mPlayPause.update();
   mStop.update();
   if (mRecord != null) mRecord.update();
 }