code: private void refreshViewHolders() {
          if (mAdapter != null) {
  
              for (ViewHolder holder : mViewHolders.getAll()) {
                  if (holder != null) {
                      // cell item
                      refreshItemViewHolder(holder, mState.isRowDragging(), mState.isColumnDragging());
                  }
              }
  
              if (mState.isColumnDragging()) {
                  refreshAllColumnHeadersHolders();
                  refreshAllRowHeadersHolders();
              } else {
                  refreshAllRowHeadersHolders();
                  refreshAllColumnHeadersHolders();
              }
  
              if (mLeftTopViewHolder != null) {
                  refreshLeftTopHeaderViewHolder(mLeftTopViewHolder);
                  mLeftTopViewHolder.getItemView().bringToFront();
              }
  
  
          }
      }
docs: Refresh all view holders