@Override
 public void closeRightContent(OnDrawerStateChangedListener listener) {
   if (drawViewGroup != null) {
     drawViewGroup.closeRightContent(listener);
   }
 }
 @Override
 public boolean isRightOpen() {
   return (drawViewGroup != null) ? drawViewGroup.isRightOpen() : false;
 }
 @Override
 public void openLeftContent(OnDrawerStateChangedListener listener) {
   if (drawViewGroup != null) {
     drawViewGroup.openLeftContent(listener);
   }
 }